Friday, April 25, 2014

No, nukes will not save us from climate change

A lot of people have been touting nuclear power - and more specifically, the “next generation” of nuke plants, powered by thorium instead of uranium - as the solution to climate change. Proponents claim these thorium-powered plants will be safer, cleaner and cheaper, and ameliorate issues with proliferation and long-term waste disposal.

But you’ll have to forgive me if I remain skeptical. We’ve had these kinds of promises of the nuclear panacea for generations now, and we should all know better than to take industry claims at face value. Last Sunday’s episode of Cosmos was a sobering reminder of how polluting corporations can buy the science they want, and how successful they can be at moving their PR through the media.

Far from answering all my concerns, the overstated claims of thorium reactor proponents raise a whole set of new ones. First, as far as cost goes, the thorium fuel cycle is likely to be even more costly. Thorium is not itself a fissile material and thus requires either U-235 or Pu-239 to kick-start the chain reaction; some part of the thorium then has to be converted to U-233 to take over the job. So thorium reactors will still require uranium enrichment or plutonium separation in addition to the costs of thorium mining and thorium rod production– all of which have a carbon footprint of their own. In a breeding configuration thorium reactors will need reprocessing, which is both costly and produces significant disposal issues. Moreover, the thorium fuel cycle creates highly radioactive U-232 as well as U-233 in the reactor, which raises worker safety issues that will be expensive to address.

All of this while the cost of solar and wind power continue to plummet - more than 75% over the past five years, and still falling. Germany’s solar array produces as much as 20 nuclear power plants on any given day. And if nuclear power is going to save the planet, the existing 400-odd reactors are going to have to be decommissioned (at taxpayer expense) and thousands of thorium plants costing billions of dollars apiece will have to be built to replace them, as well as the fossil fuel plants.

Second, the idea that nuclear waste can be turned into the next generation’s perfect fuel raises concerns. Nuke fans are talking about reprocessing, which is, as mentioned, both costly and toxic. You take the spent fuel rods and dissolve them in powerful solvents, and then you’re left with some new fuel, but also with leftover radioactive solids, liquids and gasses. All this nasty stuff still has to be stored for generations and/or transported to storage (at taxpayer expense), with the attendant risk of leaks and spills, overseen by corporations fueled by the profit motive, or mortal governments with uncertain oversight.

Third, thorium proponents are claiming that there are no proliferation issues. But as mentioned, the fuel cycle involves the production of U-233, which is just as useful for bomb-making as plutonium. Some proposed thorium fuel cycles require as much as 20% enriched uranium, which governments could easily divert for further enrichment to weapons-grade material. Thorium proponents are claiming that it can be less of a proliferation risk is the U-233 is mixed with U-238, but that will result in the creation of more Pu-238 as the reactor operates. So if you want thousands of these nukes all over the planet, you will also need hundreds of reliable governments and non-government actors who will avoid the temptation to divert either of these byproducts. And let me just add: no terrorist organization has ever planned to attack a solar array.

Fourth, this brings up the question of safety. A recent Forbes article claims solar and wind cause more deaths - throughout the entire production cycle - than does nuclear. The article doesn’t discuss the risks involved in solar energy production, but the mortality rate for wind and solar comes mainly from mining the raw materials, which would of course also increase for nuclear even if we switch to thorium fuel – first, because there’s more of it than uranium, and second, because we’ll be needing thousands of new thorium reactors.

Which also means that the risk of accidents will be going way up as well. And meanwhile, taxpayers still have to pick of the insurance tab. But new solar and wind technologies are already improving their safety rates, and there’s no reason to think that won’t continue. Either way, industry-friendly tables like the one in Forbes rely on deaths per kilowatt-hour, which makes nukes look safer because they have produced comparatively far more energy than renewables (so far). The total number of deaths from wind and solar is surpassingly small in real terms, while there have been 20 nuclear and radiation accidents resulting in fatalities, including over 4000 deaths from Chernobyl (Moreover, avian mortality from nuclear plants is double that from wind turbines).

I think the nuclear industry has been highly successful in getting friendly treatment in the press, not just lately, but over the past sixty years. Spinning tempting tales of how we can have all the energy we need with little downside distracts us from the hard work of converting to a sustainable economy. One way or another, we have to face the limits of global production capacity, and it’s still true that conservation is our number one source of untapped energy. We can’t go on pretending we can live on cheap energy forever, with the attendant wastefulness built into our transportation, construction and agricultural systems.

I will toss the pro-nukes crowd this one bone, though: since we’ve squandered the last 25 years when we could have been addressing climate change, avoiding a 2 degree increase in global temperatures will be nearly impossible at this point, and weaning ourselves off of nuclear may have to take a back seat to massive carbon reduction efforts. But putting all our energy needs into the nuclear basket would be yet another dangerous mistake.