Saturday, May 16, 2009

Nuclear Power


Nuclear power, apart from the mostly unfounded fear associated with it, is an enormously positive thing. In a "greenhouse" world, nuclear power's zero-carbon footprint is enticing. It doesn't produce a single ounce of CO2 or any other greenhouse gas. Nor does it produce any sulfur or nitrogen oxides which cause acid rain. Other than the extremely dangerous spent nuclear fuel (which I'll get to), nuclear power is the cleanest reliable power source as we have access to.

Reliable meaning predictable and dependable. Wind, solar, and water power are all cleaner, no doubt. But they are, at least presently, in order, unreliable, inefficient, and too localized to contribute meaningfully to the US power grid. A complete revamping of the grid to allow for easier sharing of power between regions and less wasteful transport would be necessary to make these options as viable as nuclear.

I'm not putting these option down. I'd love to see them replace as many coal-fired plants as possible. But that will take a lot of time and expense. Nuclear power is viable now. And its safety record is impeccable. The Chernobyl incident is the only nuclear plant accident to ever cause fatalities. Ever. Three Mile Island resulted in no deaths and minimal exposures. Compare that to the thousands of people killed slowly by particulate pollution produced by coal-fired power plants. And the newest generation of nuclear plants are even safer, relying on natural processes like gravity and evaporation instead of big valves and pumps manned by human beings.

Of course there's the issue of the spent nuclear fuel. I don't know the answer to this. Until recently plans were to store all US nuclear waste deep underground in the Nevada desert at the Yucca Mountain site. This is a much safer storage scheme then current norm of storing all spent fuel on site at the plant that produced it. But it involves transporting the spent waste hundreds of miles, during which any number of accidents could occur. President Obama put the kibosh on this plan. I don't know enough about the science here. But I do know human tenacity and ingenuity. We've managed to design nuclear reactors that take a very dangerous and wildly powerful process and make it safe. Very safe. I think we can work out methods to transport the waste just as safely. And if we begin to rely more heavily on nuclear power that is exactly what we'll have to do.

One contender to help with this issue is a new reactor design called the Sodium-Cooled Fast Reactor. It pelts the nuclear fuel with much higher energy neutrons, creating a reaction that burns the fuel 100 times more efficiently, deriving much more power from a given amount of fuel. That's exciting alone, but the increased efficiency also allows spent uranium fuel to be burned again. It's estimated that burning our current backlog of spent uranium (nuclear waste) alone in an SCFR reactor would be enough to satisfy the U.S. demand for power for the next hundred years. And reburning spent fuel reduces its radioactive half-life from thousands of years down to hundreds, making it much more realistic to sequester it away from danger.

France, as of the beginning of 2008 already derived 76.8 of its total power supply from nuclear plants. Belgium and Sweden get roughly half their total supply this way. The US, which has twice as many plants as these countries only derives 20% of its total electric supply from them. France generates so much surplus power from its reactors it sells it to other countries for profit. France also has one of the most robust health care systems in the world. You make the connection.

Here's one last element that pushes nuclear power over the top for me. Electric cars. Back in the 50's through the 70's, nuclear's hey day, electric cars were an extremely expensive, unworkable proposition. But they are necessary to allow nuclear power to help put an end to our reliance on foreign oil. There are very few power plants in the US that run on petroleum. So barring electric vehicles, nuclear power would have little impact on oil dependence. That has finally changed. Imagine a world where we derive most of our power from clean, carbon-free nuclear, wind, water and solar sources and then use it to charge battery-powered, carbon-free electric vehicles.

To me that is a wonderful prospect.

Nothings completely safe. We have to weigh the costs and the benefits of all of our power generation options. I think nuclear power, with all things considered, is our best bet for a clean, renewable power world.

No comments:

Post a Comment