Phasing Out Old Nuclear
by Matthew Formby
With seemingly constant advancement of wind and solar power, nuclear, as a form of clean energy, seems like it's on the way out. Reports about shutting down or considered closing of aging nuclear power plants, even ones without great safety records and reasonably cost-effective energy are growing. One such report, about the Diablo Canyon nuclear power plant(1) in California spoke out for all the benefit of the carbon free energy it provides. But the closing of a three decades old nuclear power plant is a mixed thing--the technology is old, and next generation nuclear offers potentially safer operation and less waste. More than the plant's age, or the technology that may eventually be available, the most pressing question is what that plant competes with now. The questions being asked here aren't just questions for Diablo Canyon or California, but for the world as clean energy is seriously pursued(2).
Statewide numbers can give a picture. Such as the fact that Nuclear accounted for about 10% of net generation. Or that hydroelectric and other renewables accounted for about 5% and 22% respectively(3). But these broad strokes miss important facts, like the inclusion of carbon emissions from biofuels, or more importantly, what kind of energy the area has. California in general has made noticeable strides towards renewable and clean energy ahead of the country, but even being in California doesn't mean a closing nuclear power will be replaced by similar clean energy. This map from the Energy Information Administration(4) shows all solar, wind, hydro and nuclear power plants.
Of these clean sources of energy, there is none for more than 20 miles. While it might be possible to transfer some energy from the nearest solar plants to areas once powered by Diablo Canyon, it won't be enough to replace it all. With it as the only commercial nuclear plant in the state, it would take an immense increase in wind and solar to match the nearly 10% of state-wide energy it provides.
Should the plant be closed, the nearest alternatives to Diablo Canyon are the Thomas M Knott Cogen and Cold Canyon 1 natural gas and biofuel plants.
The landfill gas technology used at Cold Canyon 1 and natural gas are better than coal or petroleum, but they have their own environmental risks. Depending on the technology used, more biofuel, solar, or wind would let shutting down Diablo Canyon's clean energy net an environmentally neutral outcome. With the same development, if the nuclear power plant were kept open, substantial cuts could be made in carbon emissions greater than either California's entire solar or wind industries. So for so-called environmentally conscious people to call for its closure is a bit odd.
There's certainly grounds for concern in this case: the plant's proximity to a fault line. But this risk, just as with the risk of choosing to walk, bike or drive to work, has to be weighed against other options--because we can't suddenly stop using the energy it provided. Based on the location, this particular plant would likely be replaced with an increase in natural gas--the nearest and most common energy source for California. Replacing 2240 MW, or a net generation of 18,000 gigawatt-hours a year(5), with natural gas would cost California and the world millions of tons of greenhouse gasses each year. To give it a figure, there would be: ((18,000 x 1.22 [According to an EIA estimate of CO2 emissions per energy source(6). Note that this does not include other GHGs like Methane]) x 1,000,000,000 [to convert back into the Gigawatt hour scale provided by this nuclear power plant]) / 2000 [to convert to tons] = 10,980,000,000, almost 11 billion tons of CO2 each year, if the plant was replaced by all natural gas. Those greenhouse gasses have their own, guaranteed effect.
The question cannot just be 'what's the risk of keeping the plant running' but 'what's the cost of all options?' It's also not just a question for California. There are many aging nuclear power plants in the country, and both existing or planned ones throughout the world. The dangers involved in established light water reactor power plants have been established, and there's a lot of research being done in making them safer or establishing inherently safer designs. We also know what the cost is for doing nothing--both for the environment and for energy independence. And closing a clean, safely running, and cost-competitive power plant to, in the absolute best case scenario, replace it with a similarly clean energy source is ultimately doing nothing when there was an opportunity to make strides for clean and cheap energy abundance.