Tuesday, December 4, 2007

Jet fuel

I has a request for an abstract so here it is:

It is noted that the costs of home heating with oil and with (ohmic) electricity are approaching parity. Methods to use renewably generated electricity for other needs while also heating the home are considered. It is suggested that indoor winter time food production can pay for the needed equipment and reduce carbon emissions related to transport of produce. With the anticipated reduced cost of renewably generated electricity and appropriate lighting technology a sharecropping-like business model might eventually be viable. It is found that renewable production of jet fuel using atmospheric water vapor and carbon dioxide as feed stocks could stabilize both heating and jet fuel costs while using both less land area than biomass based methods and less space in the home than winter vegetable co-heat production. Reuse of existing oil delivery infrastructure makes the conversion easier in terms of building a viable business model. It is also noted that reuse of natural gas delivery infrastructure could allow total US jet fuel use to be renewably sourced through co-production of volatile hydrocarbons with home heating, delivery to warmer regions and subsequent final conversion. A novel approach to the Fischer-Tropsch process for producing hydrocarbon fuel which relies on direct energy transfer to the catalyst using microwaves is proposed which has potential to reduce bulk heating requirements and improve loading of the reactants on the catalyst. This method should use carbon dioxide rather than carbon monoxide as an input. A possibly pedagogically useful analogy for understanding the PdV path integral is given in an explanatory note.


The average retail price of heating oil hit $3.29 a gallon this week while the average retail price of electricity is around $0.11/kWh. So, with a 75% efficient oil furnace the cost of heating a home with oil is about 3.2 cents per thousand British thermal units (BTUs), the same as for electricity using ohmic heating at 100% efficiency. And, since it is easier to selectively heat parts of a home with electricity, it is now cheaper to pull out those space heaters than to buy oil. People in Maine though, who are selectively heating just their beds with hair dryers because they are on fixed incomes need immediate relief because the cost of replacing your plumbing every year (if you don't drain it and create a public health hazard), is still pretty high. Our ambitions to set record oil company profits by violating the ninth commandment to sow violence in the Middle East have many follow-on costs.

Ohmic heating such as you get with an electric space heater has a Heating Seasonal Performance Factor of about 3.4 which is just the BTUs per watt-hour. In more moderate climates you can do about a factor of three better using an air heat pump so for people with these systems, their cost of heating is 3 times less than for oil heat.

Since I am moving over to less expensive renewable energy for electricity I've been planning on switching off of oil in any case to reduce carbon emissions but I have not settled on a heating system though I've been favoring a geothermal heat pump. For these, the constant ground temperature is used so that you don't have any ohmic heating at all since you aren't exposed to very cold outside temperatures when air heat pumps don't work and thus resort to heating coils. My resistance to ohmic heating is showing here. It is a rule of thumb that says don't waste electricity on heat since it is a much better energy source than that. As we've seen, the idea of wasting real energy does not make a lot of sense, but old habits die hard. George Monbiot, who wants to retain the use of natural gas for heating in England, wants to generate electricity in the home with a gas generator and use the waste heat from that to heat the home. My problem is the opposite, I want to use the electricity for something more useful first and then get the heat as a bonus. But, I can't really turn on enough appliances to heat the house so what to do?

One way to reduce carbon emissions is to eat locally, especially fresh greens which require a lot of fossil energy to get here from across the country. Looking at the improvements in lighting efficiency and the spectral requirements of plants it looks as though I could grow quite a lot of my winter greens with a basement greenhouse that uses blue and red light emitting diodes. Because plants are not all that efficient at using light, even when you spoon feed them their favorite colors, most of the light will turn to heat and heat the house. From my investigation so far though, it would be hard to turn this into a business because I can only anticipate a couple hundred dollars worth of vegetables which just covers the cost of equipment using the less expensive compact fluorescent lights. Also, I've run into trouble finding seeds locally. When I explained my idea to the salesperson at the hardware store where I did find some half price wax bean, green bean and pea seeds from Baltimore, I heard the same idea from him that electricity is more expensive than oil for heat, though as we've seen that is no longer really the case. I think that the potential for growing plants using renewable power is going to get better as the cost of power comes down and the cost of lighting reduces. One way to make this work would be to contract for wind power with demand management so that the lights are on when the wind blows. Then the cost of electricity should be about 6 cents per kWh and people who let their basements be used to grow plants in the winter could get a reduced price for heat. But, this is probably a few years off and individual efforts that document successes and failures would be the best way to proceed right now.

Not everyone is going to want to have a cellar sharecropper coming in and out delivering milk, eggs and vegetables every week while tending to the harvest and not everyone has an 8 foot by 10 foot space to devote to this. But, thinking more about George Monbiot's favorite subject heat, there is a valuable commodity that could be made at home using electricity and which could answer his last dilemma, air travel.

There is a fairly important paper by Agrawal et al. published this year in the Proceedings of the National Academy of Sciences that grapples with the problem of biofuels just not having much of a place in a renewable energy economy owing to the low efficiency of plants at converting sunlight to energy. The paper goes about half way to converting our transportation fuels to renewable sources by supplementing plants with hydrogen generated from electrolysis. But, they still rely on plants to provide the carbon. We can see that we need the other shoe to drop if we consider the ill-fated Biosphere II experiment compared with the International Space Station. Biosphere II needed a little more than three sunlit acres, in theory, to support the respiration of a crew of ten. The space station devotes the volume of two fairly small canisters of zeolite and a small portion of the solar power they collect to do the same task for a crew of six. We are simply much better at collecting carbon from the atmosphere than plants are. A slight modification of the scheme proposed in the Proceedings of the National Academy of Sciences paper reduces the land area needed to produce liquid fuels that cover all our current transportation as we do it now from their admirable million square kilometers to just 100 thousand. Now, we don't really need to use liquid fuels for most of our transportation. We can do much better using electricity directly. So, really, the place to look at liquid fuel needs is aviation where its use seems irreducible without cutting service. This was Monbiot's sad conclusion, that he could retain most of our activities while cutting carbon emissions but aviation would have to be cut. He morns the loss of love miles.

So, lets make renewable jet fuel without encroaching on food production or wilderness. There are a lot of ways of doing this so what is outlined here may not be the cheapest but lets just put together a system that gets both carbon and hydrogen from the air and turns it into jet fuel while heating a home all while using renewably generated electricity. First we need our hydrogen and carbon sources. These are water vapor and carbon dioxide. We'll plan on producing about 150 gallons a month of jet fuel as our maximum production rate so we need to condense about 0.4 kg/hour of water and 1.9 kg/hour of carbon dioxide. We could go higher if we concentrate on the efficiency of our production method, but remember we want to heat a house so we'll put half the energy use into the chemical bonds in the jet fuel and half into heat (50% efficient) so we want to make about as much jet fuel as we would normally burn as heating oil. The water is easily had using a standard dehumidifier running at about 220 watts. We'll prefer this source of water to avoid impurities and in a basement application a dehumidifier is often welcome. To get the carbon dioxide we'll use the same system used aboard the space station, There are other methods such as that being developed by Klaus Lackner's collaborators in Arizona which may be more energy efficient but since we are heating a home, we'll just pick one since we want the waste heat.

The zelotite used on the space station has been characterized by NASA so it is fairly easy to estimate our material and power requirements for obtaining our carbon. The amount of air we need to process to get our hydrogen at 20 C and 25% relative humidity is 100 kilograms per hour. To get our carbon we need to process more air than this, about 4000 kilograms per hour. Entraining 20 C air with the output of our dehumidifier at -10 C we get the proper air flow at 19 C. The zeolite will carry about 10 grams of carbon dioxide per kilogram of absorber at this temperature and the partial pressure of carbon dioxide in the atmosphere so assuming 20 minutes each to equilibrate in both the loading and unloading phases, and taking the the space station model of constant operation using two separate zeolite components, we need 63 kilograms of zeolite in each component. Since zeolite has about the density of water, the space needed would be about the size of two relatively small adults. So far we are keeping our apparatus to a space smaller than a regular oil furnace so that the space issue that winter time basement farming might run into is not arising here. If we want to be more parsimonious in our use of zeolite, we can use the cold outside air to load the carbon dioxide, reducing our use of zeolite by a factor of about two for 0 C air. NASA didn't characterize zeolite below this temperature, but extrapolating suggests that we might limit our zeolite use substantially more if we were willing to throw energy at the problem, chilling the outside air. But, by then we'd have heated the house because this would be a standard air heat pump. Again, other technology might be used so we won't speculate further.

Now we just need to calculate the energy needed to pump the carbon dioxide from the unloading pressure of 0.01 torr (to get better than 90% unloading) up to a pressure that will be useful for Fischer-Tropsch synthesis, about 17 bar at 19 C if our working temperature is to be near 230 C. To do this we need a 410 watt pump. So far we've used 630 watts of power collecting our hydrogen and our carbon. The rest is chemical energy, and, as Agrawal et al. point out we only really need to separate the hydrogen out of the water since we could use the carbon dioxide in out Fischer-Tropsch process though we'll look at an interesting means of producing the traditional carbon monoxide in a bit. But let us look at the land area needed to gather a kilogram of carbon. Our 410 watt pump will run for 4 months a year gathering about 0.52 kilograms of carbon an hour. So all together it gathers 1500 kilograms of carbon. To do that it would need one third of the annual output of a three by three meter square solar array. You might power air conditioning in the summer with the same array. Here we are assuming 15% efficiency for the solar array for comparison with the calculations in Agrawal et al. So, to gather 1 kilogram of carbon we need a land area patch about 7 centimeters on a side and no tractor. Now we can see our advantage over plants at collecting carbon. They need about a square meter to do the same thing over a growing season. Even though the plants provide the carbon striped of oxygen, the awkwardness of compacting soil to collect the carbon and gather it all in for processing makes it seem silly to burden our ecosystem to provide jet fuel when we can do so much more compactly in a system where the infrastructure is already in place. In Maine, small oil companies are having a great deal of difficulty because their customers are only placing small orders so that they are running all over the place delivering very little oil at each stop. Would it not be better to go pick up 300 gallons of jet fuel every two months and take it to the airport in Portland or Bangor? Would it not be better to cap the price of heating and jet fuel now by contracting with Mars Hill Wind Farm to provide the power. At a flow through rate of $0.07/kWh it may be possible to beat the current price of $2.62/gal for jet fuel. At the least, Maine's fuel assistance program should be looking at this as a means to help in meeting the State's obligations under the northeastern regional agreement on climate change.

Well, as we've seen, the energy involved in gathering the hydrogen and the carbon is not so large. The main energy involved is in converting water and carbon dioxide into jet fuel. And, this is also where the relative inefficiency of thermal processes makes the production of sufficient heat for a home a natural result. The Fischer-Tropsch process revolves around the carbon monoxide bond which is one of the strongest, higher than the ionization potential of many elements. It is the strength of this bond, 11.2 electron volts, that determines what kind of dust, silicate or hydrocarbon, that stars form at the end of their lives. Oxygen and carbon are paired up one to one in the expanding atmosphere of the star until one or the other is used up. If there is extra oxygen left then silicate dust is formed, if there is extra carbon left, carbonaceous dust is formed including large molecules called polycyclic aromatic hydrocarbons. Carbon monoxide is a tough molecule and so quite a lot of energy is needed to separate it. This is the reason for the fairly high temperature used in the Fischer-Tropsch process. High pressure is used to ensure that hydrogen and carbon monoxide get well enough layered onto the catalyst that helps to move oxygen off of the carbon monoxide molecule so that there is always another molecule to carry the oxygen away. To do standard Fischer-Tropsch we would first produce carbon monoxide from the carbon dioxide. This can be done rather elegantly using silicon as an assisted photcatalyst. If we were to use this method we would use artificial light for photons. Once we have the carbon monoxide we would mix it with hydrogen from electrolysis of the water we've collected and pass it through a kiln (ohmic heating) at high pressure within a pipe that contained our catalyst. Once brought up to temperature the process is exothermic and releases a large portion of the energy we have stored through making hydrogen and carbon monoxide. Water produced in the process would be recycled into hydrogen. This, together with the desired hydrocarbons, would be cooled by heating the home.

Perhaps alternatively we might dispense with the carbon monoxide production and use light in a similarly innovative way. Metal powders are easily heated with microwaves and microwave generators are more robust than kiln elements so we might arrange our catalyst as a powder suspended in fiberglass. Loading onto the catalyst works better at low temperatures so we might get a faster reaction if we pulsed microwaves to allow a load/react cycle. Since microwaves will tend to drive off water preferentially to carbon dioxide, carbon monoxide, hydrogen or the hydrocarbon product, we should expect the oxygen to transfer from the carbon dioxide and carbon monoxide to hydrogen to form water. If the catalyst is shaped to include sharp points, it may be that corona discharge or simply strong electric fields owing to the induced currents in the catalyst will assist in transferring the oxygen without the need to reach bulk temperatures as high as usually used. The main thing though would be the better loading of hydrogen which should eliminate coking (we've already eliminated ammonia poisoning) and thus allow the catalyst to be used for a heating season or more. The use of silicon dioxide as a supporting material could be problematic but another non-conducting material might be found to be used as a alternative. In this case, the reactions is less exothermic than when carbon monoxide is used so that we would get a greater fraction of our home heating from the inefficiency factor of the electrolyzer.

Chemistry is fun so that little bit of speculation should be taken as just that, it is untested. But, running a standard Fischer-Tropsch process to make jet fuel is proven and even certified by the Air Force. Doing it in a way that produces only fuel, oxygen and heat is somewhat novel but relies, ignoring speculation about using microwaves, on demonstrated technology. Heating is used through the day and night, so using wind power seems like a good match. One could store a bit of hydrogen and oxygen as a backup in case the wind died down for a while and use this for process heat or for just straight home heat until the wind got blowing again. Right now, carbon dioxide is an industrial waste gas produced in pure form in the manfacture of quicklime for cement for example, so it may be best to begin using that supply first rather than condensing it out of the air. External tanks of liquid carbon dioxide could be sized so that deliveries could be no more frequent than pickups of of jet fuel. Adequate filtering of town or well water could also substitute for our dehumidifier. As the cost of renewable electricity continues to fall, it is almost certain that we will make fuel for aviation in this manner, but right now, people whose incomes are low and indexed to an inflation rate that excludes both energy and food need help. Making a start at a way to make home heating pay seems like something to pursue. Here is a sketch of how the whole system flows:


Schematic renewable jet fuel production method. Energy inputs assume 100% efficiency so heat output is a lower limit. 70% efficiency in electrolysis implies and additional 3000 W of heat.

The Northeast and Mid-Atlantic originate quite a lot of air travel and are also where heating fuel is most used. It is likely that conversion of homes that use oil to jet fuel production can supply the regional demand. But, to supply flights originating where home heating does not use so much energy would require using another kind of existing infrastructure. Forming hydrocarbons up to butane and sending them from homes through existing natural gas pipelines to the South and Southwest might allow minor further conversion to be done in those regions to produce their jet fuel.

Now, if I can just find some lettuce seed....

Calculation:

I get razzed sometimes for "not doing my homework" when in fact I am just leaving out details that people who might make that sort of comment could fill in themselves. I'm trying for a discursive engaging style here where the language is evocative. I was trained to the idea, attributed to Martin Rees, that you lose 10% of your readers with each equation. Ten equations, zero readers. So, I allow the blog to be a little less easy to use in the interest of making it more generally useful. Scan that again: You might need to pull down a calculator sometimes and fill in the blanks but you should be able to read all the way through an article and enjoy it before going back to check the math. Comments are open in case I've been too opaque on the maths.

In any case, I thought of a nice analogy for calculating the work done in pumping a gas up to a higher pressure that I thought might be pedagogical so if you have read this far and are a high school physics teacher, this is all yours.

When you calculate what is called PV work where PV stands for pressure times volume rather than photovoltaic, it makes a difference how you manage things. I learned statistical mechanics before I learned standard thermodynamics so I didn't get this drilled into me as much as some of you might have. But, I understand that it can be confusing.

A lazy man's load is trying to carry too much. If you are moving a wood pile into a wood shed, a very good idea because the wood shed works harder than you do (why?), you might think that you'll get the job done in fewer trips if you really load up on each trip. The lazy man wants to make fewer trips. But, what happens is that you end up dropping several sticks along the way so that you have to go back and bend over three times to pick these up so you end up doing more work than you would have if you had just taken loads you could handle. How much work you do to move the wood pile depends on the manner in which you do it. The great bugaboo of thermodynamics is just this kind of thing. If you go dropping sticks all over the place, creating more randomness than you need to, you end up doing more work. In statistical machanics, you are increasing the number of states avaiable to the system. In thermodynamics, you are raising the temperature.

We're going to use the ideal gas law, PV=nRT, to calculate how much power we need to condense carbon dioxide from 0.01 torr up to 17 bar. A torr is about 1/760th of 15 lbs/square inch, about atmospheric pressure, and a bar is about 15 lbs/square inch. In our equation, P is pressure, V is volume, n in the number of moles, R is the universal gas constant and T is the temperature. We can adjust R to whatever units we are using, but we need to be careful about T. To see why this might be, consider making both sides of the equation zero. To get zero pressure with finite volume and material we need a very special kind of temperature called absolute temperature. There is obviously atmospheric pressure on Earth when the temperature is zero in F or C so this is not what we mean by zero temperature. We use a scale called Kelvin which happens to have the same spacing as the C scale but has a value of about 273 K when water freezes (0 C). There will be about 385 parts per million of carbon dioxide in the atmosphere by the end of the year so its partial pressure is about 0.28 torr so that is why we want to pump to 0.01 torr for unloading.

Now, we have two ways to increase P which is what we want to do. We can increase T or we can decrease V. Decreasing V is the way we'd like to increase P, but when we decrease V, both T and P go up. Try it. Get a bicycle pump and start pumping. You'll find that the base gets pretty warm. But, increasing T is a probem because the gas will eventually cool, but in the meantime you are working away against pressure that is going to come down with the cooling. This is the lazy man's load problem. If you get to 17 hot bars, you'll need to pump some more latter once the gas has cooled to get up to 17 cool bars. So, we're going to assume that the gas at high pressure can cool efficeintly as we are pumping so that we are not doing that extra work. So, we hold T constant at 19 C or 292 K. So we want to add up all the little bits of work we do to go from a large volume and low pressure to a low volume and high pressure so we want to keep track of P as we make small steps in volume and add up the products of the pressure and volume changes. When we do this kind of adding up, we notice that P changes like 1/V so the answer will look like the logorithm of the ratio of the beginning an ending volumes because that is what happens when you add up little bits of that form. This will be multiplied by the other terms, nRT, that we got when we wrote pressure in terms of volume. We know what that ratio is from the ideal gas law, it is just the ratio of the beginning and ending pressures. We are collecting 1.9 kilograms of carbon dioxide per hour so that is about 43 moles per hour. The logarithm of the ratio of the pressures is about 14, R is about 8.314 and T is 292 so we get 1.47 MJ of energy expended each hour or about 410 watts.

Sunday, November 18, 2007

Reprise

Over the last ten months we've followed the release of the Fourth Assessment Report on global warming from the IPCC. Since they've won the Nobel Prize for Peace, we don't really have to spell out Intergovernmental Panel on Climate Change anymore. We looked at the fact of global warming in February, the consequences of global warming in April and the good news that we might all prosper in May. Now there is a synthesis of all of these pieces just before the week of Thanksgiving. And, now we stand with the biggest corn harvest ever (13.2 Billion Bushels) though here on the edge of the great southeastern drought yields have been too low for farmers to break even. We might give thanks for the bountiful harvest but we might also consider if we are using it wisely. World grain stocks won't replenish based on this harvest, in part, because we are converting much of the extra yield to fuel.

Both the Australian and Southeastern droughts have had an effect on wheat supply with Tennessee and Arkansas seeing lower yields though increased land in wheat. The droughts in both areas are part of what we might expect from global warming. The Australian drought has already been tied to warming through the increase in evaporation that higher temperatures bring. The drought in the US southeast is likely just a preview of reduced precipitation expected in the region as temperatures rise. On page 890 of the Working Group 1 report in figure 11.12 we see a projected 12% reduction in summer precipitation centered on Louisiana. Already the high heat and reduced river flow have shut down a nuclear power plant in the region while an emergency declaration seeks to override environmental protections for waterways Georgia shares with Florida and Alabama. It is easy to see why the new report from the IPCC favors mitigation over adaptation. We are slow to adapt when we won't even look straight at the problem and that slowness means people won't eat as grain stocks fall. Adaptation, planting crops in new areas and abandoning old areas that used to be fruitful, takes just as much effort, if not more, than working to decrease emissions and restoring the climate to the state we have adapted to for 10,000 years. But the report itself mentions both biofuels and nuclear power on the mitigation side, so there is more thinking to be done. We can't both eat well and burn biofuels as a substitute for fossil fuels. And, we can't both wait for nuclear power plants to attempt to displace coal plants and expect them to continue to work properly in a changing climate. They take much too long to build, and then may be inundated by the extra sea-level rise that the delay causes or be unable to run without killing a river because of the higher temperatures caused by that same delay. Reliance on nuclear power does not just mean large stranded costs as plants are closed before the end of their design lifetimes owing to both changing climate and lack of fuel, but huge opportunity costs owing to the lack of investment in more suitable technology.

The reason for the inclusion of these distractions from the main task, I think, is the involvement of economists in the preparation of the report. There is a obvious distinction drawn between the growth of mitigation efforts at a rate that markets can support on their own and at a rate that whole economies can support, but these economists, because they concentrate on failures rather than successes in their training, miss the even more obvious. Many of them have benefited from a gift of land from John Bulkeley, George Downing, Samuel Winthrop and John Alcock in 1649 that has since grown into $35 billion dollars in assets.



The economists ignore this even though many of them get almost monthly reminders in the mail that this small gift of land accounts for about half the of the $35 billion owing to compounding over 350 years and the other half owing to the example the first gift set. The economists do understand the compounding part though they often misapply it as discounting, but they don't understand that their very incomes depend, in part, on this initial gift which has played such a large role in the development of their field. The work is not done, of course, since there is still an obvious lack of rigor. Because economists are used to the dead end dynamic of exploitation of depletable resources, they apply discounting indiscriminately, implicitly assuming that anything we do today has a finite benefit. Thus, they include dead end and desperate technologies like large-scale biofuels, nuclear power and carbon capture and sequestration together with endowment technologies like wind and solar. They don't see that appropriate renewable energy technology takes progressively less and less effort just as the management of the Harvard endowment needs (proportionally) less care as it grows. As the fractional cost of renewable energy reduces, prosperity increases in a way that cannot be discounted away.

Buckminster Fuller understood the different nature of the dead end technologies and the endowment technologies. Perhaps economist would gain something by considering the role a perfidious rogue has played in making the ongoing support of the study of their subject possible, and come to draw reasonable distinctions between kinds of technology themselves. It is time for wisdom to take back the helm from the discounting pirates.

Thursday, October 25, 2007

All the fish

Between high school and college I made a pilgrimage with a friend to Seattle's Fisherman's Terminal. This a port behind locks that is home to salmon boats, trawlers, purse seiners, long liners and the majestic crabbers. The salmon boats, aside from purse seiners, are mostly trollers that go out to sea using lines and hooks or those that stay in Puget Sound laying gill nets. My friend signed aboard a troller while I went out on a longliner fishing for black cod, and then halibut as the season opened. We did catch a couple of large sharks but that is another story. We did not make enough to pay the boat on that trip though so the last on was the first off and I moved to a gillnetter. We fished at night in the San Juan islands, the place I first formed my understanding that island folks are just plain nicer than others. The people of the San Juans resembled the people of Mt. Desert where I had worked before in that they recognize each others existence cheerfully. This understanding is something that has been confirmed over again in Taiwan, Japan, and Hawaii.

I can say of all I met though, there was one whose recognition of my existence has left a very lasting impression. On a moonless night with a quarter mile of net set, my skipper, who was trying to teach me the lights of the islands, knew there was something close to the net. Sensing this kind of thing was beyond me but finally, in the deep dark I did see something at the end of the net, which had a light to mark it. And then it came back. Rising above the surface of the water, three times the length of the boat came a grey whale, one of the oldest mammals on Earth. It tipped an eye up to look at us and then moved on. Now, grey wales eat shellfish, so this one, swimming up the net then back down, was just stopping by to see what was going on and to say hello. Another person making a living from the sea.

The net did not hold especially more fish. It was webbed for Chinook, but I remember there was a big King with its hook tangled. Perhaps a gesture of goodwill from the whale.

Why the fish story? Today, the UN issued its Global Environmental Outlook which said, among other things, that all current fisheries are likely to collapse by 2050. About a third of fisheries have already done so because we are taking two and a half times more fish than the oceans can produce at a steady level. Centuries ago, we thought to get energy by killing whales for the oil that could be rendered from them. The grey whale was hunted to extinction in the Atlantic. The friendly eastern pacific grey that I met might do alright if we don't take all the shellfish too.

Real Energy, the subject of this blog, can be a way to ensure that what we do does not change the habitat of species so fast that they cannot adapt, if we all work together to achieve it. But we need to know how to work together. It seems to me that when a fishery collapses because of over fishing, everyone loses and by working together we can prevent this to the benefit of everyone. If we are clever enough to catch a fish, we ought to be able to figure out how to catch just the right number. Let us make a treaty to limit our fishing to what the ocean can sustain and so gain practice for limiting our greenhouse gas emissions to a level the ecosphere can accept. Yes, we must eat less fish now, but that is better than no fish at all later.

Monday, October 15, 2007

Splash plot

My regular readers (all two of them) will have noticed that I have not posted since the end of August. This is owing to the fact that I don't mess with the blogspot format much and the August posts which remained listed in the side bar to the right amount to an outline of an energy transition that takes us to negative carbon emissions in sufficient time to avoid the most dangerous aspects of global warming. Now you are going to have to click on August to get the scoop. Since that time I've been flogging aspects of the plan around the net as my irregular readers know.

Today is Blog Action Day. So, I'm consigning the plan to the archive to try to contribute to this effort. The theme of Blog Action Day is the environment and the Real Energy Blog is very much concerned with this topic. Energy is such an important aspect of our interaction with the environment that to make positive changes, I feel that we need a new language and mythology about energy. I'm not really inventing this language or mythology. It is already there in the work of Buckminster Fuller or William McDonough or the environmental interviews you can hear on New Dimensions Internet Radio. What I'm trying to do is bring quantitative thinking into this kind of language based on fairly current energy data. Real Energy is participating in natural flows, Ghost Energy is grave robbing. The participation in the action of nature expands your soul. Grave robbing leads to tragedy. Saying this does make people uncomfortable. When I posted congratulations to the IPCC and Vice President Gore on winning the Nobel Peace Prize, I got 14 anonymous moderations of the message with the message going up and down. I take this as evidence that Gore's statement that Global Warming is a spiritual challenge is essentially correct. My message was a polite congratulations that should have received no moderation at all. Instead it became a battle ground of Brownian motion. There is much spiritual energy constellated around Global Warming.

Now, I notice that Andy's Blog Action Day post mentions Tim Flannery who wrote The Weather Makers, and this brings to mind the value of blogs to react to news. Flannery recently made a statement that the IPCC (one of the Peace Prize winners) will soon say that we have already passed the greenhouse gas concentration that will lead to dangerous warming. Within days, the RealClimate Blog came out to say that this is a misinterpretation. This is an example of how the worries that the blogosphere creates more heat than light are unfounded. There are self-correcting mechanisms.

Another example can be found in one of my August posts, where George Monbiot's statement that we might expect 25 meters of sea level rise this century is a misinterpretation of a recent paper in Philosophical Transactions.

A third example, so as not to pick exclusively on Australian activist sites, is a site that is attempting to shut down the nuclear power station at Indian Point in New York. While the aims of the site are quite congruent with the Real Energy Blog, the site has attacked Robert Kennedy Jr. wrongly by saying that he is invested in the company I sell solar power rental contracts for. The company has made it known that this is not the case in short order and comments on the post have cleared this up.

Blogging has a lot of reaction. The right wing blogs seem to be all a twitter about a judge in the UK who ruled that guidance is needed to show Gore's Inconvenient Truth movie there. They seem to be crowing that the judge found errors of fact in the movie. But, when you look at the list (google is your friend) it is clear that the judge was mistaken, and RealClimate has promised [and delivered] a response.

For my contribution to Blog Action Day, I'm going to take the big step of including some images in this blog. The first highlights what I consider to be an important criticism of the IPCC report. What RealClimate does goes in several directions. Correcting Flannery or Monbiot is a small thing. Pointing out that the IPCC report has not relied on the best available data is even more important. This plot from that post:



Points out that recent satellite data on sea level change shows a faster rate of increase than used in the IPCC report. So, like the way that polar sea ice is melting faster than anticipated, IPCC projections on sea level rise may be too conservative. James Hansen has been addressing this issue recently by considering the concept of scientific reticence. It may be that the IPCC cannot be relied upon to predict more than trends because warming is happening faster than can be captured using conservative methods. The post at RealClimate suggests 1 meter of sea level rise by the end of the century as a possible lower limit while Hansen has discussed 5 meters of sea level rise by the end of the century. This is 10 times as much as the prediction of the IPCC report.

Now, this correction comes from better data. Since I am not a climate scientist, I thought I would stick my neck out a bit with the following plot and stand ready to be corrected just like Flannery or Monbiot.

Mauna Loa measurements of the annual change in the concentration of carbon dioxide in the atmosphere (thin solid line) together with fossil fuel emissions (thick solid line) and various extrapolations. A linear extraoplation (short-dashed line) reaches dangerous climate change (450 ppm) near the year 2035 (where the line thickens). This and the exponential extrapolation (dot-dashed line) are fits minimizing Chi^2 in linear are log space respectively. The other two lines attempt to match these at the beginning and end of the measurements. They have the functional form of time to the power of time (triple-dot-dashed line) and a Gaussian (long-dashed line). The data point for 2007 is a guesstimate.

This plot is a little different from the sea level plot because it is a rate of change plot. The carbon dioxide in the atmosphere goes up every year but here we just plot the amount it has increased each year rather than the cumulative change. This is a time derivative of the cumulative change measured at Mauna Loa. This is then easy to compare with the amount of carbon dioxide that we emit into the atmosphere each year by using ghost energy as counted by the Energy Information Administration. This is the bit we control. The amount we add to the atmosphere is less than the amount that stays. The place where the thick and thin lines touch is likely accounted for by forest fires in Asia. And, unlike the sea level data, we are not likely to see better data that can help us to refine trends. The ups and downs are real and not a matter of measurement error. But, we can draw the conclusion that, like our emissions, the rate of increase of carbon dioxide in the atmosphere is accelerating. So, we can't really do better projections, and because we control the thick line, everyone uses emissions scenarios to look into the future. But, Flannery's worries lead to a question. Are there natural emissions feedbacks that could go beyond our control that are already underway? The answer is obviously yes if we look on the Asian forest fires as climate related but it is hard to make the case that this in more than a one-off event. So, the question remains open. I think that we can get a clue from the data about how bad such feedbacks could be by fitting a few functions. If there are the beginnings of a feedback, it can't be stronger that the early stages of a rapidly increasing function. So, I've thrown up an exponential function, and one that goes like time to the power of time. I thing that we can say that if such feedbacks are occurring, then they shorten the time to reaching the (nominal) dangerous level of climate change by a few years. On the other hand, if these feedbacks are present in the data, we are already in a dangerous state. It is also worth noting that gradualism is not so helpful. If we slowly reduce our emissions (Gaussian) we still reach the 450 ppm level about 15 years later.

So, that is my contribution to Blog Action Day: A diagram that is meant to spur thought and discussion. It is different from an emissions scenario approach and has some serious flaws compared to that method but it does give a little bit of a constraint on how bad things might be right now. Others might use data on forest fires or carbon uptake into the oceans to derive better constraints, but at that point would we be fitting feedbacks with feedbacks?

Thursday, August 30, 2007

Cost of Freedom

I've been expecting a revival of Crosby, Stills, Nash and Young ever since the President said that Iraq is just like Vietnam. Those haunting lyrics:

Find the cost of freedom
Buried in the ground.
Mother Earth will swallow you
Lay your body down.


fit with Iraq even better than Vietnam since if we just left oil buried in the ground, we would not be spilling blood all over the sand. And, we'd be a heck of a lot more free too. Oil, coal and gas are like the chains ghosts rattle to show their misery.

But, the President is a kidder. In Korea or Vietnam we were there by invitation under a theory that we were fighting for our own freedom. In Iraq we are fighting for our enslavement to oil because any theory that we are fighting for someone else's freedom breaks on the hard rock that we are fighting all sides in a civil war; no motive but oil is left. So, what is the cost of freedom from oil?

I mentioned already that I'd raised the idea with Phil Sharp that rationing makes the most sense. This is an idea that I'd been kicking around for a few years on green email lists. The idea would be to have a second currency (like postage stamps) but instead of rationing the way we ration money to set the inflation rate, distributing the resource at the top, we would distribute the resource equally to all so that every one's creativity would become engaged in figuring out how to get off ghost energy. The way we ration cash is a cap-and-trade system at the top of the banking system. The way to ration carbon is a cap-and-trade system at the consumer level. I want to say right now that the term white market, as I coined it a few years ago, is a ration free portion of the economy that is already off carbon. As many Amish are moving to solar power for their workshops, the goods they sell would be pretty much part of a white market already. But, I don't mind a different coinage at all. E. Swanson's idea is that the white market is the place where people who have been especially successful in reducing their fossil fuel use go to sell their extra rations to people who need more time to get things figured out. And, I don't mind calling the rations icecaps as George Monbiot proposes, but I do think that his proposal to give the government it's share for free is a mistake. Government should recover the ability to use carbon the way that it recovers the ability to use cash. Then it is apparent to citizens how well the government itself is doing on getting off carbon. Citizens can't practice eternal vigilance if the government use is not coming out of their pockets. Monbiot's view seems to be changing though compared to the rationing ideas he presented in his book Heat. He does not mention granting rations to the government here but he is still concentrating on rations for electricity and fuel rather than having the rations trace fossil fuel use throughout the economy. (Note to George: the highest rate of sea level rise mentioned by Hansen et al. (2007) is 5 meters per century, it could go higher but when talking about 25 meters they say centuries rather than millennia. See this response at realclimate.org.) Ultimately, icecaps need to trace back to as close to the mine or well-head as possible to be retired. In the case of oil, many will be retired at the tanker, for coal at the mine and for imported goods at the border. It is doubtful to me that the WTO will object to requiring rations appropriate to the use of fossil fuels in the manufacture and transport of imported goods since all goods face the same treatment. To get a low ration burden a Chinese manufacturer need only use solar power and a sailing ship.

At first, the total rations match current use and then the total issued is reduced each year reaching zero at a particular date. That date should be set so that the impact on total demand for oil and gas is substantial even if production is curtailed for physical reasons such as the effects of exhaustion of the resource. The date should also be set to minimize the cost of carbon dioxide sequestration out of the atmosphere that we may well need to undertake. Finally, we need to work within a time frame that makes converting the transportation fleet, electrical energy sources and home heating feasible. The shape of the curve to zero should likely be steep at first down to a 20% reduction because conservation can manage this kind of reduction fairly easily and this saves everyone money. The time-scale for energy source conversion is about 20 years at the present rate of growth of renweables (45% annual) while the longest time-scale is for home heating since oil and gas furnaces last a long time. Fleet conversion has a shorter time-scale since automakers anticipate putting plugin hybrids on the market in 2010. Their retooling could take 5 years from that point so that fleet turnover would be nearly complete in 17 years. Monbiot urges a 23 years to zero emissions date. Very cheap renewable electricity might persuade those who rely on oil or gas for heat to convert before their furnaces are worn out so his date may be a good choice. A 5% of current use reduction per year for 4 years gets us to cheap oil and gas and captures the low hanging fruit of conservation. The remainder of the curve though would be nearly as steep at 4.2% of current use per year. Taking the date at 2035 would have us reducing at 3% of current use per year after the first four years, a rate that enhanced economic activity owing to lowering energy costs could likely sustain. Continued growth of the US renewable energy industry over the following few years after US zero emissions would cover world energy needs and would be produced below the cost of production of fossil fuels so that any lagging countries would be easily persuaded to get with the program. Presumably our balance of trade will be nicely positive as a result. This would also be the time to undertake technological carbon dioxide sequestration efforts since this would be the point at which the cheapest renewable energy equipment could be produced most abundantly and also the point at which we would know what scale of effort will be required.

The most important aspect of people-level rationing is that it makes a transition to real energy affordable because it reduces the cash price of coal, oil and gas by reducing demand. A carbon tax makes things more expensive by raising (cash) prices so people do not see the benefit in their wallets and don't have extra funds to buy a new plugin hybrid electric car, for example. Tax shifting only works up to the point where there are remaining taxes to shift and a rapid transition would need a very steep carbon tax which would likely overrun current taxation. Rations give everyone room to maneuver, a bit of freedom on the way to even greater freedom.

Wednesday, August 29, 2007

The Undertaking

The reason, I think, that people get so infuriated with James Hansen is that he has such a long track record of being right much sooner than other people. He's the kid in class who gets the answer not only first, but right away, no sweat. He's also the kid who just blurts out the correct answer without being called on. So, people like the President attempt to censor him and there is a great roaring on the internet when some data published on the web has an unimportant flaw (see he's not perfect).

So, here comes another flap. A newspaper article has misquoted a new paper by Hansen and co-workers saying that they are predicting 25 meters of sea level rise by the end of the century. And, a number of blogs are cranking up the ridicule. But, if you read the paper you'll see that they predict 25 meters in centuries, not this century. This is still important because it is not 25 meters in a thousand years, but you end up with several meters by the end of this century, not 25 meters.

Let's work backwards in the paper because there is some really big new at the end that the newspaper article missed. First the last footnote:

The potential of these 'amber waves of grain' and coastal facilities for permanent underground storage 'from sea to shining sea' to help restore America's technical prowess, moral authority and prestige, for the sake of our children and grandchildren, in the course of helping to solve the climate problem, has not escaped our attention.

Back in the day, colorful footnotes used to set apart some of the better academic writers but you don't run into these as often now. The footnote is about a scheme to sequester carbon dioxide from the atmosphere by burning plants to make electricity and then squirting the carbon dioxide down below the bottom of the ocean where it should stay put. The big news is not about the particular scheme, which is a little awkward, but that they are discussing sequestration at all. This is a big departure because up until now Hansen has been saying that there is likely a decade or so over which we might simply reduce emissions and thus avoid a large sea level rise. Sequestration is likely to be more expensive than just reducing emissions. The cost to build a coal plant that captures carbon dioxide for sequestration is about $2.20/Watt while thin film photovoltaic panels are being manufactured now at a cost of $1.19/Watt. So, where we would be saving money by reducing emissions, adding on a requirement to clean up the mess we've made already through technological intervention could add to our costs. There is a large prize being offered to figure out how to do large scale sequestration and make money too so it may turn out that we'll learn that sequestration saves money as well, but so far, adding sequestration to a coal plant looks as though it adds about 40% to the cost of building a plant. For a biofuel plant there may be similar costs and since the methods we know to get photosynthesis to scale up to our energy use involve needing a source of concentrated carbon dioxide, a sequestration plan based on burning grasses won't have a big impact on the atmospheric CO2 concentration even though growing grasses does help. Biological methods to sequester carbon dioxide from the atmosphere, if needed at scale, probably have to occur in the oceans though the potential of coastal regions to support much more mineralization should not be overlooked. At a guess though, since we are seeing so much progress in shifting from thermodynamic to quantum means of generating electricity, a technological approach to sequestration of carbon dioxide from the atmosphere will leverage the very low cost of electricity and high availability of energy we can anticipate to use chemical sorbants that can absorb carbon dioxide from the atmosphere much faster than plants can so that we minimize the land use impacts of our clean up effort.

Again, the big news is that Hansen is calling for sequestration of carbon dioxide out of the atmosphere rather than what particular method is given as an example. So, why the change? Let's keep working backwards:

The best chance for averting ice sheet disintegration seems to be intense simultaneous efforts to reduce both CO2 emissions and non-CO2 climate forcings. As mentioned above, there are multiple benefits from such actions. However, even with such actions, it is probable that the dangerous level of atmospheric GHGs will be passed, at least temporarily. We have presented evidence (Hansen et al. 2006b) that the dangerous level of CO2 can be no more than approximately 450 ppm. Our present discussion, including the conclusion that slow feedbacks (ice, vegetation and GHG) can come into play on century time-scales or sooner, makes it probable that the dangerous level is even lower.

This is it, we won't go farther though the paper seems virtuosic. They find no evidence that ice sheets linger once the temperature goes up when they examine big climate changes in the past. That makes changes in ice cover and plant cover into an additional feedback that boosts warming on a shorter time-scale than usually assumed. This puts us in a position where just reducing carbon dioxide emissions as quickly as we can may not be enough. The solution to global warming would then involve reversing it, not just ending it. And, this is why the position has changed.

Change sounds like just what we may be needing to lay on the eyes of the ghosts we have dug up to ferry them back where they belong. All the more reason to get real about energy so we can save our pennies for the task ahead.

Monday, August 27, 2007

Many more ghosts

You never get a response from the New York Times if you submit a letter to the editor aside from an auto-response in the case of email. On the other hand, they don't want material submitted or published elsewhere so we're a bit stuck. I'll leave it up to them if they want to carry this.

The New York Times had a pretty good editorial on Thursday urging Congress to investigate the recent mining accident in Utah. They feel that some decisions of the Mine Safety and Health Administration (MSHA) could have played a role in the deaths. In the following letter I agree with them but point out again that the reduced productivity for coal mining implies that even more strenuous safety efforts are needed than those that in earlier years led to reduced annual mining fatalities. So, Congress take note:

Your Editorial, "Unsafe Mining" of August 23, 2007, rightly points out that continuing to reduce coal mining deaths after last year's rise will require greater effort and Congress should look into the specifics of the most recent disaster to understand how an MSHA official died, how the mine came to be reopened and if any official corruption was involved. That Gary Jensen, an MSHA inspector, died in the rescue attempt is very concerning since his experience is lost and cannot benefit the avoidance of future accidents. This, more than anything else, even the upsurge in mining deaths last year, suggests that the MSHA is not able to do the job it once did in reducing mining deaths.

But Congress also needs to go beyond understanding the institutional breakdown in the MSHA to a broader picture that we are moving towards diminishing returns for coal mining. An MSHA operating as it once did may not be able to reduce the number of mining deaths each year as it has in the past. A study conducted by the Energy Watch Group this year finds that in the US the per miner productivity has been declining since 2000 and energy production from coal has been declining since 2002 owing to greater reliance on poorer quality coal. This indicates that at a given level of safety, a larger number of miners must die each year since ever more miners must be employed to compensate for the reduced productivity. The report suggests that outsourcing our mining deaths could not be sustainable since China and Australia will soon see similar declines with only Former Soviet Union countries boosting production out to 2050 but with world production in decline after 2030. So, an MSHA that would continue to reduce mining deaths as it once did would need to work much harder than it has in the past because it will need to protect many more miners. For a grieving agency this may seem like hard news indeed, but Congress must push it to greater efforts. NASA has now returned a school teacher safely to Earth. The MSHA can take inspiration from this.

Relying on depleting resources inevitably means greater danger as the more easily obtained and higher quality portions of the reserves are exhausted. The days of Phoebe Snow and the Road of Anthracite are long past but now we are coming to a more serious turn: do we double the 104,621 deaths that got us from 1900 to 2006 as we dig deeper for lower quality coal or do we go to the extreme to preserve life?

Wednesday, August 22, 2007

What the dormouse said

Note: Mr. DeVore has responded in comments linked below.

I don't know why Chuck DeVore, Orange County Assembly Person would insult the California utilities he says he wants to help, but he seems to be a bit deranged in most of his arguments. He wants to repeal a long standing law in California that bans new power nuclear plants. To open, he insults Californians, calling them hypocrites because 80% of them don't carpool or use mass transit. He is outraged that California will cut greenhouse gas emissions by 25% in 13 years while growing 20% in population. For 7 million new people, that's about 400 new homes a day. Every day I hear of a new housing development in California with solar power built in. What part of 2 gigawatts doesn't he understand? And, what of existing homes? While new applications for rebates for solar installations were falling off earlier this year owing to time-of-use rates, applications for rental of solar power systems were more than covering the deficit. As of today there are more than 3,600 applications for no-rebate systems which don't immediately show up on the million solar roof books. Will the existing homes in California have fewer installations than the new homes? What part of 6 gigawatts doesn't he understand? Why, this is the capacity he is proposing for new nuclear power all in thirteen years.

He has particular problems with understanding electricity. He proposes that out-of-state power sources would suffer huge transmission losses and argues that nuclear power should not be sited out of state because of this. But he must not know that the Pacific Intertie already supplies LA from Washington and manages this distance quite well. But, since LA already sucks the Colorado River dry, north is about the only direction he can go to site new out-of-state nuclear power while closer solar installations like Solar One will require less in the way of new lines. In fact, north is the only direction he can go for new nuclear power even in-state since coastal sites will face the risk of sea level rise and are unsuitable for new nuclear power plants. So, what he really wants is for the City of Sacramento to build four new nuclear power plants to power southern California. But then he'll have to wait for the levy system to get repaired because Sacramento faces its own flooding issues. And with the changing flows that loss of snowpack will bring, the Sacramento and American Rivers may experience the same kind of problems that shut down reactors on the Tenneseee River and in Europe. So, four new nuclear power plants in the middle of the State Capital to be started after the levies are fixed (10 years) and the law is changed (? years) and taking 6 years for completion gives a minimum of 16 years before any electricity is produced at all with no certainty that the plants can even operate under changing flow conditions. The lack of realism is astounding. Perhaps it is not so much that the utilities are risk adverse as he demeans them, but rather they not raving mad.

He makes another astounding statement: converting transportation to electricity would require doubling generation capacity. This shows a complete lack of understanding of the poor efficiency of the internal combustion engine. Electric transportation is much more efficient and would require at most a 30% increase in generating capacity and likely much less. But most roofs can provide this, so the 8 gigawatts of solar capacity that we may easily anticipate from home roofs alone make a very good start on this.

Others of his deluded statements include that life cycle carbon dioxide emissions from nuclear power are lower than for solar power: Nuclear plants can't be built without fossil fuels and concrete and nuclear power plants can't be recycled while solar panels don't require fossil fuels to make and recycling makes their net energy ratio higher than any other power source.

His plan to change the law in California also apparently hinges on a plan to change the federal law aimed at preventing weapons proliferation. So, now he has to change two laws and meet a 13 year deadline. These are talking points, not serious proposals. The people of Orange County should take a good look at who is paying for the nuclear kool-aid he's been drinking and give him a good long rest.

Tuesday, August 21, 2007

Tuppence in the Sun

Mr. Dawes Sr. If you invest your tuppence wisely in the bank, safe and sound, soon that tuppence, safely invested in the bank, will compound! And you'll achieve that sense of conquest, as your affluence expands! In the hands of the directors, who invest as propriety demands!

The lyrics to the song that follows this bit of wisdom in the musical Mary Poppins can be found here. The next song, Step In Time is much more energetic and it is perhaps understandable that a song about compound interest would fail to catch on.

We are seeing a lack of propriety these days in a number of financial transactions. The slicing and dicing of risk seems to have led to a question of what value many securities have if any at all. But, if you want to take on projects that extend over a substantial period of time, credit markets are likely to be a part of what you do.

One thing we need to do is transform how we get energy and a number of options include long term components. Nuclear power, for example, extends so far into a climatically uncertain future that it is seeking extra help with finance through federal loan guaranties.

While renewable energy is forever, its implementation can be taken in 10 to 25 year chunks so it fits much better with standard lending terms. Further, risk is low so while raising capital though venture mechanisms can happen, it is also attractive to banks, especially since renewable energy equipment can serve as insured collateral. This is why so much of the financing for renewable energy is coming from institutions like Credit Lyonnais and Morgan Stanley especially in the commercial sector. In the residential sector, solar power equipment is being rolled into a mortgages for new home construction while installers for existing homes are getting savvy at helping customers find financing through secured credit based on increased equity.

But, what if you want to follow the commercial sector model of separating ownership of the equipment from the use of the equipment in the residential sector. Individually financing each deal, as might work for supplying Walmart with solar power, becomes time consuming and thus expensive. What is needed is an aggregate instrument. One way that aggregation has been used with propriety is the securitization of leases. CVS, for example, financed its eastern expansion based on the security provided by the fact that it had property leases to conduct its business. This brought them lower cost financing since the aggregated leases were more secure than individual leases.

One way to secure low cost credit to allow the long term use of solar power on homes is to secure the credit on the basis of an aggregate of rental contracts which assure repayment of the debt. So long as those contracts are sufficiently attractive that few of them are likely to be broken (they save customers money) then you have a low risk security that does not require high interest. This is the form of financing that Citizenre has adopted for its solar power equipment rental business. Shaving the cost of financing puts it in a better competitive position than attempting to work out deal-by-deal financing, so much so, that it can afford to ignore state-level rebates available to individual purchasers of solar power equipment.

There is certainly room for venture capital in the solar power business, especially for high risk new technology development. But, for deployment of proven technology, the model being adopted in the commercial sector using more traditional financing leads to cost savings that are important for market competitiveness. Carrying this over to the residential market, with its much larger roof space resource, will likely rebalance the solar market towards an acceleration of its current 30% annual growth.

Monday, August 6, 2007

Cliffhanger

People who should really know better are beginning to say we should consider nuclear power as an alternative to coal power as a way to reduce carbon dioxide emissions. One person, who should be careful, has made history by being the first female Speaker of the House of Representatives. Her district strongly opposes nuclear power, and it is even illegal in her state to build new nuclear power plants. She may feel that she now represents the other members in Congress who elected her speaker, but she won't be Speaker for long if she stops representing her district. She is not required to abandoned the positions that got her elected to Congress just to be Speaker unless she became Speaker in a dishonest manner, promising to betray her constituents in exchange for power.

Another person who should be too smart to go for nuclear power is James Lovelock. His work towards understanding why the environment of the Earth is suitable for its inhabitants has been quite interesting. His thinking is that the world appears to take care of itself, adjust its atmosphere to keep a stable temperature, for example, because of feedbacks within the ecosystem. The ecosystem, viewed as a whole, acts to preserve itself in the same way that your body "acts" to keep its temperature stable. I was so impressed with his review of his work on a model called Daisyworld that appeared in Nature some years back, that I sent a copy to my daughter. It is a very simple model that acts as though it "knows" what is best for itself. Just a few simple behaviors on the part of some flowers controls the temperature of the whole world even as the luminosity of the Sun increases. In other words, life preserves itself as though all of life were aimed to do this without requiring collusion. Niches are adaptive in addition to species adapting to niches. Perhaps the problem is that Lovelock is looking for simple solutions, but he does not realize that nuclear power does not follow simple rules and so cannot fit into a self-stabilizing model.

Let's look at how this would break down. In the Power Plant World we have black power plants that warm the Earth and white power plants that cool the Earth just like the flowers in Daisyworld. As the Earth warms, a shift from black power plants to white power plants ensues. But, in Daisyworld there are simple rules, in Power Plant World there is an additional rule that the waste from the white power plants cannot touch the water. Now, we set the model to run. The temperature initially increases spurring a decrease in black power plants and an increase in white power plants, but the temperature continues to climb, as it must, because there is lag that is not present with the albedo mechanism used in Daisyworld. This means that the water level rises even as white power plants become more numerous and black power plants less numerous. And, the rule that the waste from white power plants can't touch the water has a devastating effect. It is so expensive to keep the waste from white power plants from touching the water, that when they die, their cores, which are very dangerous waste at that point, are usually just buried in place. But, when the water level rises, these cores have to be moved and buried somewhere else because of the don't touch the water rule. Moving the cores requires more energy than the white power plants produce in the first place so the whole system collapses.

Actually, in Power Plant World things are not really as black and white as they are in Daisyworld. There are also green power plants that can produce much much more power than either the black or white power plants can, so there is a happy ending which would not occur if white power plants were used.

Now, the purpose of the Daisyworld model is not to represent the full complexity of ecology, it is just to show that simple rules can lead to self-regulation. The purpose of Power Plant World is to show that adding more complex rules can destroy that self-regulation. We might add more and more rules to the construction of white power plants to perhaps avoid problems like sea level rise inundating their sites or warming temperatures requiring large cooling towers. We might anticipate where river flows will be large owing to climate change and put new white power plants there. In Daisyworld there is no planning, which is kind of the point, but in Power Plant World, there would not be more white power plants without anticipating the effects of the black power plants.

In fact, Power Plant World runs on good intentions with imperfect foresight, a combination that can lead to hellish results. But, it is pretty adaptable. The white power plants were never intended to regulate the temperature of the Earth, but rather as a bribe to limit the number of countries with nuclear weapons so that the chances that we'd blow ourselves up would be reduced. The idea that they might be used for temperature control only came up after it was realized that temperature control might be needed. Both white power plants and black power plants tend to kill those who are involved in running them disproportionally, so it is strange that the people who run them love them so much. But, this strange love, like a moth at a candle, has meant that there has been acceptance among the white power plant lovers that the rising temperature caused by the black power plants is a problem so they might be able to make more white power plants even though most people don't like them.

Nuclear power plants are very wasteful so they are very thirsty. To compete with the coal power plants, they have to be big to reduce costs, and since they waste most of the energy they produce, they need a way to get rid of that wasted energy so they pretty much need to be sited near a flow of water. Big coal power plants have similar problems because they are also wasteful, but they still try to get bigger to compete with the white power plants. They have somewhat fewer constraints though because they can shut down more easily if the waste heat becomes a problem, and they send a lot of their waste heat up a smoke stack, reducing their dependence on a flow of water.

Let's look at a particular example since we can see that the Power Plant World model has too many variables and interrelationships to be all that helpful. Calvert Cliffs has been a favorite of the strange love crowd because it got a licence extension even after the Three Mile Island accident made it quite clear that nuclear power is a very bad idea. It was a matter of letting thing cool down politically, and, as we will see, cooling down, in a radioactive sense, is going to be the issue that will make this license extension look very very foolish. Calvert Cliffs is a little unusual because it does not have cooling towers but rather relies on predictable tidal currents to carry away waste heat. It is located on the Chesapeake Bay right at current sea level. It has also recently submitted an application to build a third reactor at an estimated cost of $2.35/Watt, construction only, much higher than the capital cost of a wind farm ($1.30/Watt) which does not require fuel. You can see already that political rather than economic thinking is at work here. And, there are further political considerations. Maryland will be meeting all of it's new generation need with renewable energy as a result of its Renewable Energy Standards Portfolio, so the new generation from Clavert Cliffs will be for export, saddling the people of Maryland with the risks of nuclear power without any benefits.

Let's look at the 20 year license extension granted in 2000. The current reactors will be running until about 2035. But, the climate reports we have been studying predict that sea level rise is going to be more that two feet possibly before the end of the century. Non-linear effects on the ice sheets could bring this up to 15 feet by the end of the century. But, because of the international treaty, it is not legal to dispose of nuclear waste in the oceans. So, the reactors will have to be moved. Basically you can not move a reactor until it has cooled for a century so the licence extension means that the reactors cannot be removed to comply with the treaty until 2135. But, sea level rise will be 3 feet by that time pretty much for certain and the reactors in noncompliance with the treaty without drastic engineering on inundated and very soft muds. So, not only does the sea level rise imply that a never before tried reactor removal must be undertaken, but the license extension means that it must be done at even greater expense. The correct way to proceed would be to revoke the licence extension and even the license to operate so that cooling of the cores can commence now. A cost estimate for removing the cores in 2107 should be developed now, and a surcharge placed on other nuclear generation to cover this cost.

As noted above, the new reactor under consideration will be much more expensive than other forms of power, and it makes no sense to build a new reactor in a place that will be underwater even before the end of its design lifetime. But, even granting that it can be designed to remove the reactor as soon as needed rather than waiting for the hottest elements to decay, its construction costs cannot be levelized over the anticipate design lifetime, but only over a much short site suitability period. This likely brings the cost of power above $0.09/kWh, especially since credit markets are becoming aware of the risks associated with sea level rise. Federal loan guarantees don't really help this situation since they merely guarantee that default will occur, shifting costs onto the taxpayers. Similar conclusions have been drawn about proposed new reactors in England.

Nuclear power is anything but nimble. Very long timescales must be considered. The fact that the industry has been invoking global warming as a reason to build more plants, taken together with the fact that they have made Calvert Cliffs their success story example makes clear the need to scrutinize all of their proposals with much greater care than was taken in granting the license extension. The consequences of climate change: sea level rise, changing river flow patterns and heat balance need to be independently assessed for current reactors to see what increased costs are coming so that they may be added as surcharges now. There are a number of plants whose reactors will need to be removed to higher ground by the end of the century and these need to be identified and shut down to allow cooling time. Granting licences for new plants should be put on hold until such a study and surcharge apportionment can be completed. The industry's obvious inconsistencies in the case of Calvert Cliffs make their own assessments nearly useless. Either they have been disingenuous in their claim that a license extension was justified or they have been disingenuous in their claim that they have the foresight to make such a case since they quite obviously acknowledge the reality of climate change.

Will those who ought to know better come to their senses before they drive up the cost of energy by a factor of two or more while delaying real action on climate change? To be continued....

Wednesday, August 1, 2007

The Roof Pitch

Abstract: This one is long enough for an abstract so here goes:
An estimate of the available US residential roof surface area is made and the fraction of current net generation that can be replaced with solar power is as much as 46% using this area. Policy issues that could hamper full attainment are discussed. A new fast Norwegian model for electrifying transportation which also provides 0.5 days stationary storage of total generation is considered and found likely to move rooftop solar from its policy limited maximum fraction of 22% towards 46%. Utilities are advised to avoid long term purchase contracts for new nuclear power.

All the trees behind my house were cut down during nesting season with machines straight out of The Lorax. The machine would grip the trunk and, with a high pitched whine, the machine would sever the tree from the ground in about 4 seconds, then back off carrying the tree upright and drop the tree somewhat indiscriminately out off the way. Last fall I put together a new metal shed (with much cursing for the last bits of roof that were hard to get to). It turns out that the old wooden shed was on property that is to be developed in front of the house and it was so old it could not be moved. Doesn't leak though. Nothing has been happening though since the trees were all cut down out back. It could be that houses won't sell for what the developers thought they might so they are holding off.

I don't quite know why we are building so many houses. There aren't that many more of us. Maybe it is the divorce rate. We need two houses per family.

Trees are what grow over most of my neighbor's homes. I picked mine to have sun and a south facing roof. I used to live under a ginourmous sweetgum tree and it's shade cooled that house in the summer, but a good bit of insulation in this house seems to work better. But, with trees being slaughtered using those strange contrivances which, I'm sure, violate Dr. Suess' intellectual property rights, I'm not going to suggest that my neighbor's homes be included in these calculations. We'll estimate assuming all roofs get sun, but there is no suggestion that those that don't should. And, with things slowing down in the building trades, we'll use numbers from a couple of years ago which might compensate for some shady roofs.

What are we doing? We're going to calculate how much sunlight can be turned into electricity just using home roofs. The thing is, FedEx, Google, GM, Coke, Walmart, Kohls, Target, BJs, Cosco, Staples and other businesses are all turning sunlight into electricity using their roofs so they can save money. But, their buildings use so much energy that only about 30% of what they use can be covered this way. But, a house can cover what it needs pretty easily because we tend to like a little less activity at home. Keeping the doors open for shopper past midnight to sell a book about a boy wizard would not allow us much rest. So, can houses make up the difference so that businesses can run on 100% real energy too?

These calculations came about because Robert Rapier had been looking at biodiesel and finding that it would be quite hard to cover transportation with what could be produced. Robert is a contributor to The Oil Drum which we've scolded before. His conclusion was that the future is solar. The main reason is land use. If we use rooted plants to get real energy, they don't put all their efforts into just converting sunlight into stored energy. They are more interested in their social life, hobnobbing with bees, sharing delicious seed holders for dispersal and generally sharing news through their roots. So, as we've seen, only a little bit of real energy is available for harvest compared to all that was used. Robert decided that if we want to have food, we can't also grow fuel at the level that we use it. Now the standard example came up that a square of land in Nevada about 80 miles on a side running a solar thermal plant at 20% efficiency can produce all the energy we use. This is an easy calculation: Nevada has regions that get 9 kWh per square meter of sunlight per day on average over a year, or 375 Watts per square meter of average power. At 20% efficiency you get 75 of those. So we just divide the 1.2 TW of energy we use that we calculated earlier by 75 W per square meter to get the number of square meters we need. Divided again by a million gives 16000 square kilometers. The square root of this, 126 km, gives the length of the edge of the square which is about 80 miles.

Now, many people objected that this was impractical even though it was just an example of how little land is actually needed compared to what we farm. So, we set to calculating what could be done with roofs since this is surface area that is already being used. We need an estimate of the size of a typical roof, how many roofs there are and what the typical available sunlight is. This is a rough estimate (remember the trees) so we won't do anything fancy like match houses in states with the solar resource in that state.

Let's begin. For a home size we'll take 1700 sq ft from 2002, for the number of houses we'll take 124,500,000 occupied and vacant from 2005 and for the available power we'll take 5 kWh/m^2/day from the middle of the country. We're going to adjust the home size which comes out to be 158 m^2 down to 100 m^2 because some houses have more than one story. We'll only use half the roof (50 m^2) assuming that this is the south facing side, or if we cover east and west facing surfaces we only get to use half at one time. Then we'll take a system efficiency of 17%. Each roof then produces 1.8 kW as average power (5 kWh/m^2/24 hours* 50 m^2 *0.17). All roofs produce 0.22 TW. In 2005 average net generation in the US was 0.46 TW (4.055e12 Wh/365 days/24 hours). So the roofs can provide 46% of the electricity the nation uses. But the residential sector uses 37% of the whole generation. The roofs can thus provide extra power for the businesses but they can't cover the whole thing, only about half of what businesses can't do for themselves. Hydro and wind provide about 9% of generation so we are looking for another 100% -(30% of 35% = 10% commercial solar)-(46% residential solar) = 35% to cover the rest of the commercial and also the industrial sectors. Wind power can certainly do this while, as we saw in the case of the Nevada example, solar farms on non-agricultural land can also work.

Just like the businesses that are converting as much of their power use as they can to save money, homes can do the same thing and it turns out we can get a majority of our electricity using just roofs. All of this works essentially under net metering and 41 states have such laws. But many allow the utilities to confiscate the excess power produced within a year of generation. So, unoccupied homes should not be counted in this circumstance. Also, their are few incentives for landlords to save their tenants money so we might want to consider only owner occupied homes. With these limitations, we only get 60% of the residential sector or 22% of the total. These restrictions would seem to be more important than shading from trees. There is some transfer between the rented, owned and vacant buildings so we'll likely get to close to the whole residential sector eventually, and, for the vacant homes, with the utilities confiscating over production, there should be little reason to maintain artificial caps on net metering capacity since they'll see a very healthy overall 11% profit if the owners of the vacant properties don't put in server farms or some other means of using the power generated at the property. We should note that this is actually a huge profit because distributed generation means that expensive upgrades to much of the distribution system can be delayed or avoided all together. In fact, it may well be that utilities can maximize profits by paying a fraction of retail for generation above use rather than nothing. In that case, as the cost for panels comes down, their may be an incentive to use all of the roof.

But, there is a much more important thing coming that will increase the fraction of roof area that is used. The ghost energy depleting industries that we want to displace like to use talking points that emphasize how little real energy we a using right now. They'll sometimes acknowledge the 30% growth per year in renewables, but then pick a date about 15 years before that growth shuts them down to say that the amount of generation will still be small. Then they say that we need more coal, oil, gas and uranium to meet projected demand, hiding the fact that new capacity there will be very expensive because it won't ever be used for its design lifetime. They also ignore the fact that the dollar cost of real energy is plummeting while the dollar cost of ghost energy is only going up. The effect this has of the growth rate can only be positive, especially since renewable energy fabrication is so nimble compared to power plant construction. So, a 150% annual growth rate may not be out of the question. A number of individual companies are planning 100% annual growth just to keep their market share high, a number than investors look at closely. Planning for 100% annual growth takes some doing, but it is much less cumbersome than gaining approval for a new nuclear plant, especially in today's security environment.

The thing that is coming is actually a new business model for transportation that will increase the amount of power people use at home while decreasing the amount of gasoline they use. Companies that manufacture hybrid vehicles are saying that they expect the cost to manufacture these will be the same as for their other lines in a few years. The reason for this is that though the systems are a little more complex, the cost of retooling per unit goes down as the share of production goes up. These vehicles can be modified to have electric only operation with a range of about 40 miles by adding more batteries. But, the batteries are expensive even though the cost of running the vehicles is much less expensive. Batteries, like solar panels degrade in performance over time but for different reasons. For solar panels it is high energy particles which degrade performance while for batteries it is use which degrades performance. The behavior of solar panels has interesting implications for the estimation of the quantity Energy Returned Over Energy Invested (EROEI) because this becomes quite dependent on what level of performance you are willing to accept. If you cut off at a 20% degradation in 25 years, with a 2 year payback time, you get a value of 12.5 trending towards 25 with recycling (because you don't have to purify the silicon again). But, if you accept a 60% degradation you get a value of 33 trending towards 66, the highest for any energy source. You might be willing to accept a 60% degradation if you are replacing the lost performance with less expensive more efficient panels as needed so long as you still have roof space. With batteries for transportation, you really have to set a lower acceptance criterion for performance degradation because the car won't get so far with degraded batteries. Battery degradation also depends on the manner of use. Transportation is a tough environment while managed power storage is a benign environment because an individual battery can be treated gently.

The new business model for transportation takes advantage of this behavior of batteries. Noticing that at least 75% of a battery's useful life will be outside of a vehicle, a company in Norway is planning on leasing about a quarter of the of a battery's life for transportation then selling the remaining battery life to utilities for the power storage we need. Stationary storage does not need nearly the performance levels required by transportation. Now, transportation is about 28% of our total energy use with most of that in trips under 40 miles. By passing batteries on to utilities, the transportation sector will be providing storage for about half of our total energy use. You might think it would be 84%, but using batteries is much more efficeint than gasoline engines so the transportation sector energy use will shrink by about 2 thirds. The business model greatly reduces the cost apportioned to transportation for batteries, making electricity as a transportation fuel very attractive, while at the same time saving utilities money on their most expensive generation costs by allowing storage to cover peak demand. This makes mostly electric transportation the least expensive, especially since people will add capacity to their roofs at lower costs when this mechanism comes in over the fleet replacement timescale. The effect of this is to increase residential use of electricity by about 30%, and similarly increase the contribution of the residential sector to distributed generation. But, the businesses that are adopting solar power now, won't get this energy because it will be displacing gasoline use instead. Notice, though, that the increase in electricity demand this implies is met with real energy even under current net metering policies (excluding overall caps).

In consideration of this, to maximize profits, investor owned utilities should be pursuing a policy of divesting themselves of ghost energy generating capacity, avoiding like the plague very long term ghost energy purchase agreements, especially for any new inflexible nuclear generating capacity, and encouraging rooftop solar as much as they possibly can while working out clever ways to profit from the approximately half day of energy storage they can anticipate coming in from the transportation sector. In short, they should adopt a supermarket or warehouse business model, where they profit by the continual exchange of real energy that their distribution networks can provide. And that is the pitch for rooftop solar.