Nuclear Power

Reads at about grade 5Both sides shown9 sources cited

Nuclear power splits atoms to make heat. That heat makes electricity all day and night, with no fossil fuels burned.

What it is

Nuclear power splits uranium atoms to make heat, which makes steam that spins turbines to make electricity. While running, a nuclear plant makes almost no carbon pollution, and it also makes "firm" power -- electricity that flows around the clock, in any weather. Solar and wind are different: they only run when the sun shines or the wind blows. California has one nuclear plant left: Diablo Canyon, on the coast near San Luis Obispo. It provides about 16 to 17 percent of the state's carbon-free electricity, or roughly 9 to 10 percent of all its power. State officials say the plant helps prevent blackouts during extreme heat and lets the state lean less on natural gas. Federal regulators renewed its licenses into the 2040s, but state law only lets it run through 2030 unless lawmakers vote to extend it. Experts agree on the main trade-offs, but not on the bottom line. The upside is clear: the power is low-carbon and runs around the clock, and officials say that steady supply helps keep the lights on in extreme heat. The downsides are real too. The used fuel stays dangerously radioactive for tens of thousands of years, and the U.S. still has no permanent place to store it -- a federal count found at least about 65,000 metric tons stored at 75 sites in 33 states, and the pile grows each year. Building new reactors has also been very costly and slow: Georgia's Plant Vogtle cost more than $30 billion, over double its first guess, and it opened years late. People fight over one question: is nuclear's steady, clean power worth those costs and risks? This debate even splits environmentalists.

How it works

Nuclear plants use uranium, a heavy metal, and splitting its atoms -- a process called fission -- releases a lot of heat. That heat boils water into steam, which spins a turbine that makes electricity. Burning coal or gas does the same job, but it sends carbon dioxide into the air; nuclear does not. Diablo Canyon started running in the 1980s, and for years California planned to close it by about 2025. Then, in 2022, fears of blackouts changed the plan, and lawmakers passed a bill, SB 846, to keep it open longer. In 2026, federal regulators -- the Nuclear Regulatory Commission, or NRC -- renewed its two licenses to 2044 and 2045. But state law still says the plant can only run through 2030; to go longer, the Legislature must vote again. People debate nuclear because the trade-offs are big, and they pull in different directions. Supporters see clean power that never sleeps and helps fight climate change. Critics see high costs, an old plant near earthquake faults, and radioactive waste with no home. Unusually, this fight splits environmentalists -- some want nuclear to cut carbon fast, others want it shut down -- which is why the debate does not follow the usual left-right lines.

The debate — equal weight, both sides

The case for nuclear power: clean, always-on energy

A mixed group. It includes climate-focused Democrats, many Republicans, and some pro-nuclear environmentalists. More green groups back it too. Not a clean left-right split.

Nuclear is clean and always on. The Clean Air Task Force, a group that backs nuclear, calls Diablo Canyon "the largest source of firm, zero-carbon electricity in the state," and one pro-nuclear analysis says nuclear "runs nearly all the hours of the year." Solar and wind only work when the sun shines or the wind blows, but a grid must deliver power to a set place at a set time. That kind of power has "no obligation to meet the demand," so it leaves a gap -- something else must fill it. Closing Diablo early would backfire, supporters say: the same group warns it would create "tens of millions of tons of global warming emissions" and push the state onto "more expensive and polluting power," mostly natural gas. California's own energy agency agrees the plant is needed -- state regulators found it "needed to support grid reliability" and warned of "energy supply shortfalls during extreme weather events." The Clean Air Task Force goes further, calling Diablo part of "the lowest cost and fastest path to a zero emissions grid." Supporters say cheap solar looks good on price alone, but that hides the real value of power you can count on all day and night.

The case against nuclear power: cost, waste, and safety

Also a mixed group. It includes green and anti-nuclear groups. Some fight for lower utility bills. Others watch the plant's safety. But some climate activists still back nuclear.

Nuclear is costly, and the waste and safety problems are real -- building new reactors has cost far more than planned, and keeping old plants running isn't cheap either. Critics say Diablo costs ratepayers about "half a billion dollars per year." Since 2020, California has added "27,000 megawatts" of new clean power, "mostly solar and battery," and critics say that money would be better spent on cheaper renewables, since batteries can also store solar power and release it when the grid needs it. The waste has no home: spent fuel "remains dangerously radioactive for thousands of years," yet the country has nowhere to bury it, so tons of it pile up on site. Safety worries add up too -- Diablo is old and sits near earthquake faults. Opponents say PG&E "repeatedly postponed essential metallurgical tests" on the reactor's aging steel vessel, and one group warned, "We will not sit idly by while PG&E cuts corners on Unit 1's safety." For them, the risks outweigh the benefits.

Sources

Behind the summary

Cited by "The case for nuclear power: clean, always-on energy"

Cited by "The case against nuclear power: cost, waste, and safety"

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