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....

1 comment:

Cyril R. said...

The cost for nuclear projects have escalated again recently.

Moody's estimated $5000 - $6000 per kWe.

The FPL 2200 MWe project has been revised to $5780 - $8071 per kWe.

The FPL 3040 MWe variant has been revised to $ 6256 - $ 8005 per kWe

The NRG project, based on FPL ABWR, but for 2700 MWe is estimated at $ 5062 - $ 6488 but they include some transmission costs, so substract a couple hundred.

Progress Energy: $ 6300 per kWe.

Reference with details

Notice the part about efficiency/renewables as well.