Monday, April 30, 2007

The Green Numbers

With all the racket about the color green these days, it seems a little hard to remember the simple principles of grassroots democracy, social justice and equal opportunity, ecological wisdom, non-violence, decentralization, community based economics, gender equality, respect for diversity, responsibility and sustainability. Maybe it was a mistake to name a movement after the color of money, but then not everyone's money is green. But, you had to pay for that first link, so maybe the noise is not so deafening that we can't think a little bit for ourselves. The green movement is definitely not about geo-political war mongering, it springs out of hope rather than fear. And it is not a throwback to the flat earth society, it is future focused.

But, as Luke 14:28 points out, if you are going to build for the future you've got to see if you have what it takes to complete the effort. So, let's start counting the green backs. We are spending a huge amount of money to little purpose, servicing debt and keeping forces in the field. So, it might not seem as though we've much wiggle room, especially when larger and larger costs are looming. But, our credit is not as extended as it has been in the past so long as we can inspire confidence among potential lenders. (Open that last link in another window. We'll be using it.)

How can such confidence be inspired? The proper way to borrow is to not really borrow at all but invest. It is just fine to borrow to pay for a road that will last as long or longer than the period over which the debt is repaid. This is not so much borrowing but rather acknowledging that the benefits of the road will be spread out in time and so the costs might be fairly spread as well. Borrowing to cover current accounts or to service debt, however, is not the way to inspire confidence. Part of the huge peak in the last link was investment in the GI bill. Bucky Fuller attributes prosperity since then to this one thing. Future Focus does actually work pretty well. The figure showing the US national debt as a percentage of gross domestic product (GDP) is a ratio. So, some of the ups and downs reflect increased or decreased borrowing and some reflect decreased of increased GDP. For example, GDP fell about 25% from 1929 to 1932 so this accounts for most of the increase in the percentage of GPD that the debt represented during this period. It took a while for idea that bold, persistent experimentation might be the proper response to a crisis, a policy that another wise man named Franklin would have approved. A period of fruitful investment ensued which is shown by the continued increase after 1932, until the war effort took over in about 1941. We reached the highest ratio in 1946, after the war at a level of 120%.

Here is the question we have to address: Is a national debt that is 120% of GDP a bad thing? Well, lets look at what a young family does. A thirty year mortgage might be issued at 7 times gross annual income leading to about 25% of income going to housing over 30 years. So, that is 700% of gross family product (GFP) initially, and if income remains stable it would be an average of 350% over the 30 years. A lot of families think of their home as an investment since they get back at least a portion of what they pay for it if they sell. For secured credit, much higher numbers than 120% are routine. The continued borrowing after the war, to properly handle demobilization, was also an investment that assured prosperity, but it was done on the good faith and credit of the US government, which some feel isn't worth the paper it's written on. History, however, is not on their side. The US does not always keep it's promises but neither has it defaulted on acknowledged debt.

Let's conservatively take 120% of GDP as a dept ceiling in the case of a crisis and on the assumption that we will be borrowing to invest rather than to cover current accounts. Can we transform our dangerous current accounts borrowing in energy into an investment in money that leads to prosperity rather than the rather unforgiving debt collection practices of ecological collapse?

Where we stand now is that debt is about 60% of GDP and is close to $9 trillion dollars so let's assume we have $8 trillion of credit to work with. It is not at all clear that we actually have this much because we need willing lenders in addition to our willingness to borrow. And, since money for lending is probably invested somewhere else right now, we'd need to look carefully at what would happen if we attempted to redirect those investments. But, we are considering a complete shift in the way we use energy, so there is a clear economic sector where money might come from. Transforming ExxonMobil into a lubricants company and Peabody Energy into a Christmas novelty company would free up quite a lot of dollars.

The US uses about 35.2 quadrillion BTU (quad) of energy a year and wastes about 56.2 quad a year owing mostly to thermodynamic laws. Let's consider solar photovoltaic power as a limiting case, since some consider it expensive, and for simplicity since we can largely ignore the wasted energy and concentrate on the used energy because we won't be dealing with a heat engine. First we'll convert quads per year to watts and get 35.2 quads/year * 1.06e18 Joules/quad / 3e7 seconds/year = 1.2e12 watts, or about a terawatt. So our final number is we can spend $8/watt capacity installed. Is this feasible?

A 500 MW solar fabrication plant costs about $600 million and at this kind of scale estimates of installed cost come in at about $4/watt. Over twenty years, such a plant produces 10 GW of capacity so the cost of plant construction is only $0.06 per watt capacity with the rest of the cost being in raw materials, operation costs, transportation and labor for installation. Now, to get to a terawatt over 20 years we need 100 such plants. Actually, we should multiply by 3 or 4 to account for the fact that the Sun isn't always up. Let's take 3 since we might not be finished with hydro power in twenty years. So, our initial investment cost in solar power fabrication plants is $180 billion. But, as noted above, we make spending outlays of this size just to keep troops in Iraq. Now, at $4/watt installed the cost of power is $4/watt /6 hours/day / 365 days/year / 25 years of installed life * 1000 kw/watt= $0.073 per kWh. Oops, this is less that I pay for delivered electricity now. So, since I'm paying more than that anyway, maybe private financing would be the way to go for that part, especially since there is obvious collateral to secure the credit. It is beginning to look as though the green numbers indicate that we don't have to go any where near the level of public debt we were at in 1946 to completely transform our energy use to renewable energy. And, we'd actually save money.

Since the cost of building a manufacturing plant is such a small fraction of the total cost, perhaps the thing to do is to build 600 of them and preserve 300 of them to handle recycling 20 years on. Or, just keep them going beyond our needs and reverse our trade deficit. The next thing to look at is how much we could save by using electric transportation, geothermal heating and air conditioning and such. We could boost our disposable income by quite a bit by financing these things in a sensible way. So, with more than $7 trillion of credit still left to play with, perhaps the proper government role would be to invest in a strategic energy reserve through renewable energy storage, though I doubt this would cost as much as this project, still well less than a trillion dollars.

The green numbers look more than feasible, they look far superior to the ghost energy numbers. Sometimes it takes a crisis to realize that you could have been doing much better all along and maybe green is the color of money. Now, if we just made the GI Bill universal.

Sunday, April 22, 2007

Smelling Salts

That last entry was a little gloomy so let's revive ourselves a little and shake off the stupor with a few thoughts on energy storage. So far, we've given a little consideration to flywheels, biofuels, gravitational potential energy and load shifting (demand side management). Let's consider something that is just a little bit like a battery. Batteries are chemical storage of energy. Sometimes they are just constructed as chemical reactions waiting to happen (as when you stick two different kinds of metal into a lemon) and sometimes they are made so the chemical reaction can go forward or backwards depending on whether the battery is charging or discharging (like the lead-acid battery in your car). Batteries are an important kind of energy storage and they are already used in many off grid real energy systems. Their technology is also improving pretty rapidly as hybrid electric vehicles start to prove themselves and push demand.

Here I want to talk about chemical storage of solar energy because of a new discovery. Ammonia is used in making fertilizer and the process for making it is called the Haber-Bosch process and it works by stripping hydrogen from natural gas and combining it with nitrogen from the atmosphere at high pressure and temperature using and iron catalyst. This is an incredibly big deal because this process allows us to grow grains on the same piece of land season after season, in your eye Mr. Malthus! This is also why ethanol fermented from grains gives so little back as a biofuel. The natural gas feedstock and the heat from burning natural gas to get the needed high pressure and temperature mean that a lot of fossil fuel is used to make this kind of ethanol. Rooted plants don't turn solar energy into stored energy with a high efficiency in any case though they do great things for our food chain and air supply.

Ammonia is also a fuel. It oxidises to nitrogen and water and it can be used in turbines or fuel cells. In Australia there has been some work on using ammonia as a substitute for water in the basic hydrogen fuel picture. Under high pressure, ammonia is heated by concentrated sunlight over a catalyst and dissociated, the reverse Haber-Bosch process, and then recombined to produce heat again at a later time. But this requires the high pressure of the Haber-Bosch process. Oxidizing ammonia can occur at close to atmospheric pressure which means less equipment. What has caught my attention is the idea of synthesising ammonia using solar power by making aluminum nitride first. This can occur at low pressure. The next step is to mix the aluminum nitride with steam to produce ammonia and recover the aluminum oxide that was reduced using solar power to form the aluminum nitride in the first place.

Reduced? Oh No! That involved carbon! Well, the folks who thought this up were interested in fertilizer and they found a way to avoid burning fossil fuels needed to get the Haber-Bosch process to go, but they still need the feedstock. That is a big step by itself, but if we want a fuel, we'd better not be sending carbon into the atmosphere just to make it. Not to worry. When methane is used as the carbon source you get carbon monoxide and hydrogen out in addition to the aluminum nitride. These can be recombined using a catalyst to get methane back so the whole thing can be closed cycle. A biological process might be even better, cycling the carbon monoxide through ethanol and then cracking. One then gets a hydrogen stream for free.

Does this compete with the efficiency of photovoltaics? It might not matter. By the time we are ready to say energy storage is the crucial next step, real energy will be quite a large part of our energy use and so long as we're there, we can be a bit extravagant if we're not encroaching on arable land. My guess is that it could compete because the main step, the endothermic production of aluminum nitride, should stick: that is, one is not going to be fighting the reverse reaction since the carbon monoxide carries the oxygen away. This is the step at which energy is stored and so long as the reaction goes quickly enough this will be the main draw on the solar power rather than the radiative and convective losses. The ammonia formation is exothermic and can probably be used to help pre-heat the main reaction. Burning the ammonia in a turbine may not be as efficient as using it in a fuel cell but it may also fit the on-demand profile for this kind of energy storage a little better.

Remember, we're thinking about energy storage ahead of time because this is where real energy is taking us. We have a whole list of posibilities and any one or two might do the job. I thought I'd poke at this one because I thought the idea that we can make ammonia from the Sun is pretty neat. Clover can do it too so be sure to plant some in your yard so you won't need all of that lawn fertilizer every year. You only need about a pound of seed which costs about four dollars and you'll be good for the next twenty years or more.

Saturday, April 7, 2007


The next summary of a portion of the new report on climate change is out and even without the Highway to Extinction charts or a proper caution about sea level rise it is pretty gloomy. As pointed out in the first summary, the temperature rise caused by us is real. Now we learn that it is having real effects now. People have died already in heat waves assigned with medium confidence to warming. The way people hunt in the Arctic has been changed owing to warming. And, as the insurance companies are already noting, coastal flooding is also becoming a problem. In the first figure of the report, the changes are represented by blue and green dots. For the US, they seem to pour off the Rocky Mountains towards Senator Inhofe's Tulsa office in an accusing flood ready to sweep on over the President's Texas ranch.

It is true that these guys bear some responsibility for our slow response to warming, or at least their submission to their paymasters is culpable, but even if we did not intend it, we have caused the deaths in Europe, disturbed the Inuit and poisoned the mangroves by causing the warming. The way our pushers use the money we pay them to keep on pushing their product does not absolve us.

Up to now, we can plea to manslaughter and unintended destruction of property, but beyond this point we will have to admit to murder and vandalism.

How well does this metaphor work? As long as it is someone else who is killed or someone else's island that sinks below the wave it goes along pretty well. Reading further into the report though, we see that we'll be harming ourselves too. At that point, we're not just being cruel, we're being stupid. If we're merely beasts soiling our den, then we bear little responsibility since we aren't capable of taking responsibility. Al Gore calls warming a moral issue. He could be wrong.