Diablo Canyon, Climate Change, Drought, and Energy Policy

Diablo Canyon Nuclear Power Plant, courtesy PG&E

The announcement that Pacific Gas and Electric (PG&E) will close the Diablo Canyon Nuclear Plant when its current operating licenses expire in 2025 has caused what can only be described as consternation mixed with occasional conniptions among the nuclear industry and some strongly pro-nuclear groups.

That’s understandable. Diablo Canyon is aging, but is not the oldest nuclear plant in the fleet and PG&E could have chosen to push for a renewal of the license to continue operations for many more years. Diablo Canyon’s two reactors are also California’s last operating nuclear plants, following the closure many years ago of Rancho Seco near Sacramento, and more recently, the last of the San Onofre reactors. As such, the closure is symbolic of the broader woes of the nuclear power industry in the United States, which has been unable to build new reactors and is seeing the current reactors being shuttered, one by one.

The decision to phase out Diablo also rankles those who see all non-carbon energy sources as critical in the fight against the real threat of climate change. This has led to an internecine dispute among those who claim the mantle of “environmentalist,” who are legitimately concerned about climate, but who split on their positions around the pros and cons of nuclear power.

I get it. The climate threat is the most urgent one facing the planet and shutting down major non-carbon energy sources makes it that much harder to meet carbon reduction goals. But old nuclear plants have to be retired and replaced at some point, simply due to age, economics, and updated environmental challenges. It would be great if there was a new generation of replacement reactors that was safe, cost-effective, and reliable and if there was a satisfactory resolution to the problem of nuclear wastes and accumulating spent fuel. But at the moment, there isn’t. The good news is there are other non-carbon alternatives available.

And Diablo Canyon faced a unique set of problems, including the need in the next few years to replace its old once-thru ocean cooling system with a far costlier, but more environmentally friendly system, challenges with steam generators and a growing risk of leaks, the long-standing earthquake risk at the site, and cheaper alternatives. Even with the sunk costs at Diablo Canyon, these challenges made it clear that cheaper options exist and “that California's new energy policies will significantly reduce the need for Diablo Canyon's electricity output.”

Moreover, the claim that current nuclear energy is cheap is false: even at Diablo Canyon – never a cheap nuclear plant – additional updates to address existing problems could cost a massive additional $10 billion.  As Peter Bradford, a former member of the U.S. Nuclear Regulatory Commission said,

“The unraveling of the [hoped for nuclear] renaissance was not a surprise to anyone who understood the workings of the power markets.”

Diablo isn’t shutting down tomorrow. The plan gives the utility nearly a decade to phase out the plant and replace it with renewable energy and energy efficiency. As the official announcement notes:

“The Joint Proposal would replace power produced by two nuclear reactors at the Diablo Canyon Power Plant (DCPP) with a cost-effective, greenhouse gas free portfolio of energy efficiency, renewables and energy storage.”

This time frame is important. When San Onofre closed its last reactor in 2012, with no formal replacement plan in place, there was a short-term spike in natural gas consumption (worsened by the simultaneous arrival of a multi-year drought, which cut hydroelectricity generation) and an increase in California’s greenhouse gas emissions. Nuclear proponents cherry pick this point as evidence that shutting Diablo will similarly lead to an increase in emissions. But within a couple of years, the rapid construction of non-carbon wind and solar systems made up for San Onofre’s lost electricity, and natural gas use -- excluding excess natural gas burned to make up for lost hydroelectricity due to the drought --dropped again. The Figure below shows total non-fossil fuel electricity generation in California from 2001-2015 (solid red line) and what it would have been without the drought (dotted red line). Without the drought, expansion of new solar and wind completely made up for San Onofre’s closure.

Total non-fossil fuel electricity generation with (solid red line) and without the drought (dashed red line). Data from US EIA. Total non-fossil fuel electricity generation with (solid red line) and without the drought (dashed red line). Data from US EIA.

With the longer timeframe to prepare for closing Diablo Canyon, and with the specific agreement to accelerate investment in renewables, there is no reason California’s carbon reduction targets can’t be met. Will they? We don’t know: that ultimately depends on the nature and timing of efforts to continue California’s transition to non-carbon energy.

But even this argument misses the key point: While it is certainly far better from a climate perspective to replace old fossil fuel plants rather than old nuclear plants, even old nuclear plants have to be replaced eventually. We should keep them open as long as feasible from an economic, environmental, and safety point of view, but when the decision is made to replace them, make sure other non-carbon generation and energy efficiency options are part of the decision.

That’s what happened here and it is a model for the future.

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Is it not naive and arrogant to assume that puny man can effect climate change? Man-made climate change is a grand hoax, at best.


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CHECK OUT MY BLOG. http://steve-finnell.blogspot.com

By Steve Finnell (not verified) on 24 Jun 2016 #permalink

Gee, I'd tell you to look up the difference between the word "effect" and "affect" in the dictionary, but that's the least of your problems here.

This is, simply put, nonsense.

Diablo Canyon will be mostly replaced by natural gas and emissions will increase if the Joint Proposal by PG&E, IBEW 1245, and anti-nuclear groups is approved by the California Public Utilities Commission (CPUC) and upheld by the courts.

Further, the percentage of electricity PG&E derives from low-carbon energy sources will decline from 58 to 55 percent.

The Proposal claims it will replace the 17,660 gigawatt-hours of low-carbon electricity produced by Diablo Canyon with an equal amount of low-carbon electricity, but the details of the Proposal make clear that will not happen. The Proposal’s specifics mandate:

1) 2,000 gigawatt-hours per year of reduced energy consumption through energy efficiency by 2025;

2) Another 2,000 gigawatt-hours per year of “GHG free energy resources or energy efficiency” to come on line by 2025;

3) There is no 3.

That’s it: 4,000 gigawatt-hours per year of (mostly) energy efficiency and (maybe) renewable power to replace 17,660 gigawatt-hours from Diablo Canyon.

Where will the remaining 13,660 gigawatt-hours come from? The Proposal doesn’t say, but the only source it can come from is natural gas.

And with all of that natural gas will come 5.4 million tons of extra carbon dioxide emissions every year.

Read More: Why Diablo Canyon Will Live — and the Corrupt Proposal to Kill It Will Fail

What about energy storage? The Proposal itself admits, “energy storage, by itself, is not a source of energy,” which may be why it doesn’t bother setting storage targets.

What about the 55 percent (of PG&E sales) Renewable Portfolio Standard by 2031 (to last through 2045)?

That sounds good, but it starts 6 years after Diablo Canyon would close, and it’s actually a stepdown from PG&E’s current GHG free share of generation, which was 58 percent last year.

So all the efficiency and renewables the Proposal mandates—or vaguely promises—would leave PG&E’s energy mix slightly dirtier in 2045 than it was in 2015—no progress at all for 30 years because of Diablo’s closure.

And while it might constitute a nominal replacement (almost) of Diablo Canyon, it would likely come by buying Renewable Energy Certificates from out-of-state renewable plants, leaving California’s in-state generation markedly dirtier. Under that RPS mechanism, California has met its nominal renewables targets even as the GHG free share of in-state electricity generation has fallen by 20 percent over the last decade.

The reason the Proposal doesn’t call for replacing Diablo with renewable energy is simple: California’s grid can’t handle it. The state is already struggling to integrate intermittent renewable power, and is having to curtail mid-day surges of solar to avoid destabilizing the grid.

The Proposal acknowledges that Diablo must be closed to make room for curtailed solar. (Of course, replacing clean nuclear power with clean solar power does nothing for the climate, although its great for the solar industry.)

But it also states that closure will “impact the efficient and reliable balancing of load,” which means blackout risk. That’s why the Proposal is careful not to mandate any more destabilizing solar or wind—and leaves the door wide open for reliable gas generation.

Which leaves load reduction through energy efficiency as the main (though woefully inadequate) green component of both the Proposal and PG&E’s forecasts. But while energy efficiency is great, load reduction is plumb stupid as climate policy.

Grid electricity is the easiest part of the energy supply to decarbonize, so we should be using more electricity—for transport, heating and other purposes—not less; PG&E’s generation should grow mightily to accommodate all the Tesla’s and Volts Californian’s could be driving on electricity from Diablo Canyon. The Proposal’s prescription for grid austerity marks a disastrous wrong turn for California energy policy.

All of this fits a growing pattern. Despite green groups’ claims that nuclear power can be easily replaced by wind, solar and energy efficiency, recently closed plants from Vermont Yankee to California’s San Onofre have been replaced overwhelmingly with fossil-fueled power. With Diablo Canyon, at least they are admitting ahead of time that renewables can’t do the job.

Read More: Why Diablo Canyon Will Live — and the Corrupt Proposal to Kill It Will Fail

By Michael Shelle… (not verified) on 24 Jun 2016 #permalink

This is normally too long for a comment, but I know how strongly Mike S. feels about this, so here you go.
I won't respond except to say we'll see what happens. Recent experience in California and elsewhere shows the potential for tremendously rapid expansion of non-carbon renewables and efficiency. If they don't expand rapidly enough, then indeed, California's non-carbon energy will be lower than desired. Time will tell.

As one who strongly supported the renewable tax credit extension as a means of cutting CO2 emissions, I am really unhappy to see those credits being used to exchange one carbon-free source for another.
This is bait & switch on a gigantic scale.

Anti-nuclear groups should not expect support from those of us who take climate change seriously.

By keith campbell (not verified) on 30 Jun 2016 #permalink

Goodness, we have a time traveller from the near future!

Well, now you've told us what happened when we closed that plant down, care to let us know the winners of the derby over the next few years?

Or were you being a nostradamus and "predicting" the future based on what you want to be considered, not what evidence you've considered.

What a silly comment. We ALL make predictions based on past experience and evidence (What route to work should I take based on my experience with traffic every day; when's the best time to shop at the store to avoid crowds, etc.). The past is a helpful guide to the future. And how is this different than the equivalent "predictions" that shutting down Diablo Canyon will lead to MORE natural gas?