Bill Gates has been lobbying Congress to secure federal financial support for nuclear power and for a nuclear company in which he is a large investor. This plea for federal largesse from a decabillionaire illustrates why further nuclear subsidies make no sense.

Nuclear power is already a heavily subsidized 60-year-old industry with over half a trillion dollars invested in several hundred large operating nuclear plants, including 99 in the United States. The cost of nuclear power has soared while the cost for other low-carbon power options — including wind, solar, batteries and energy efficiency — have plunged. This is why no U.S. utilities want to build nuclear plants unless they can get large additional subsidies.

Gates’ rationale for nuclear power can be summarized as follows: Given the reality and gravity of climate change, nuclear provides the only large-scale, very-low-carbon electricity source that cost-effectively can provide power at scale when needed. Other very-low-carbon options, such as wind and solar power, batteries and energy efficiency, cannot reliably provide power when needed — especially on hot summer afternoons when air conditioning loads are large.

This same argument was made by nuclear advocates 30 years ago and is even less true today.

At the time, I co-authored a widely referenced study comparing nuclear power and energy efficiency as alternative ways to slow global warming. Our work showed that because nuclear is far more expensive than energy efficiency, given limited energy investment capital, if investments in costly nuclear power displace cheaper energy-efficiency investments, it would have the net effect of increasing global warming. Nuclear remains a large and important source of very-low-carbon electricity but energy efficiency has delivered far more CO2 reduction at far lower cost.

Gates' argument for nuclear power was made 30 years ago and is even less true today.

Energy efficiency has cut electricity demand by half over the last 30 years and can cut growth in electricity use by half again by 2050. Gates has said his dream is clean energy at half the price of coal. Energy efficiency is now about half the price of coal. And large-scale solar contracts are being signed at close to half the price of coal, so Gates’s dream already is coming true. Forbes, in a 2018 article titled "Plunging Prices Mean Building New Renewable Energy Is Cheaper Than Running Existing Coal," noted, "Across the U.S., renewable energy is beating coal on cost," and that new solar is commonly less expensive than existing, already-built coal plants.

Perhaps as importantly, U.S. industry and buildings are rapidly adopting the capacity to rapidly reduce or shift (PDF) their power demand as needed, a phenomenon I have described as "buildings as batteries." PJM, the largest power market in the United States, already secures more than half its 15 percent standby capacity from contracts for on-demand energy efficiency at a fraction of the price of nuclear power.

And a proliferation of innovative firms such as NEST, Tendril, AtSite and Ohm are making energy efficiency an increasingly flexible resource. California-based Ohm, for example, enables and connects more than 50,000 smart devices to balance the grid, including Teslas, smart home thermostats and smart plugs. It is close to a zero-capital-cost equivalent of batteries, and is enabling greater grid reliability and expanded reliance on renewable energy while reducing consumer cost of power.

Resilient and secure?

In effect, power demand, once static, is increasingly flexible and responsive to utility price signals, making the grid more resilient and secure and reducing the need for continuously operating nuclear or coal plants.

Wind and solar made up more than half of all new generating capacity in the United States and Europe over the last four years, adding more generation capacity than all other power sources combined. And with costs declining, wind and solar are generally projected to continue to be the dominant source of new power generation. Meanwhile, America’s most valuable corporations — including Apple, Google, Facebook and even Gates’s Microsoft — are shifting to 100 percent renewable energy (PDF) to power their companies and data centers, both to save money and to enhance their brand by cutting greenhouse gas emissions. Clearly wind and solar can — and do — provide power at scale.

This leaves us with Gates’s most complicated argument: that baseload power such as nuclear is almost always on and so can be relied on to provide power that other low-carbon energy solutions cannot.

But unlike energy efficiency, which is always working, nuclear plants experience accidents that cause abrupt plant shutdowns that have been very expensive for states ranging from California to Louisiana. When a huge nuclear power plant has an unplanned shutdown, it is far more disruptive than small plants going offline. This and nuclear plants’ highly radioactive materials is why security analysts and the military worry about the vulnerability of nuclear plants to accidents or to terrorism. The projected cost of cleanup for military and civilian nuclear waste is over $490 billion, according to a 2018 study by KPMG for the U.S. Department of Energy.

And we still have not figured out a long-term strategy for storing highly radioactive spent fuel from nuclear power plants. The issue of nuclear waste disposal remains unsolved, with huge costs pushed down the road, and until these problems are solved a nuclear expansion does not make much sense.

Gates is right that nuclear plants usually operate more reliably and predictably than wind or solar plants. A single solar or wind installation has unpredictable power availability, but as solar and wind resources are added across the country’s grid, their combined predictability and reliability rises because if it is not windy or sunny in one place, it is windy or sunny elsewhere.

As wind and solar generation continues to expand, their combined reliability and availability keeps rising and may exceed that of nuclear power plants.

As wind and solar generation continues to expand, their combined reliability and availability keeps rising and may exceed that of nuclear power plants. Further, the growth of inexpensive natural gas power generation has expanded the amount of power generation than can be started up and shut down relatively quickly and efficiently (which nuclear and coal plants cannot do), making natural gas a natural complement to wind and solar — which, unlike natural gas plants, have zero fuel costs.

In much of the United States, batteries are already a cost-effective way to shift up to two hours of electric load — for example, from the middle of the day when there is a lot of sun to later in the afternoon when solar power generation drops but air conditioning use peaks. Batteries, particularly lithium-ion batteries, are scaling very rapidly, driven mainly by electric cars, and that is reducing battery costs by about 10 percent (PDF) per year. And electric car batteries are increasingly being plugged into the grid to allow car owners to profit from buying power when it is cheap and not needed — and selling back to the grid when it is needed and expensive — reshaping load around demand and availability of wind and solar power.

Consumers, businesses and utilities all win with this new distributed clean utility because renewables plus efficiency and batteries is available as a very resilient, near-zero carbon solution to providing power when and where it’s needed at the lowest cost. As these technologies continue to scale, they continue to experience steep cost declines, making the idea of a nuclear alternative vanishingly unrealistic.

Even with enormous government subsidies and guarantees, corporations and utilities do not want to invest in nuclear power.

Tens of billions of dollars have been spent developing different nuclear power plant designs, and even with enormous government subsidies and guarantees, corporations and utilities do not want to invest in nuclear power. Gates is a large investor in a nuclear firm, Terrapower, which hopes to build a prototype by 2030. If this target is achieved and a prototype is demonstrated by 2030, it could move toward commercial deployment in the 2030s. But we cannot afford to wait 15 or 20 years to scale very-low-carbon energy — and, fortunately, we don’t need to.

Renewable energy has more than doubled in the last decade to provide 20 percent of U.S. electricity, as much as nuclear. And while nuclear power in the U.S. (and Europe) is declining (although expanding in China), wind and solar continue to expand at double-digit rates as their large cost advantage over nuclear grows. Wind power costs a tenth of what it did 30 years while the cost of solar PV has dropped by over 95 percent. The Wall Street bank Lazard in November noted that the cost of solar and wind had dropped 13 percent and 7 percent, respectively, just over the past year, while the cost of nuclear is now more than three times the cost of wind or solar.

Nuclear’s competition with efficiency, renewable energy and batteries is over, and we should be glad of it. After all, renewables and efficiency provide about five times as many jobs per dollar invested as nuclear power and don’t impose nuclear power’s risks of long-term radiation, accidents, unresolved and vastly expensive nuclear waste disposal challenges or the potential to provide materials for nuclear bombs — issues that most citizens are or should be concerned about.

Nuclear energy has played an important if expensive role in providing low-carbon power, and these plants should operate as long as they are safe. But America, including corporate America, has moved on to safer, cleaner, faster and more secure options that are proving to be a resilient and low-cost path to a very-low-carbon grid.

Gates should do the same and shift his formidable skills and capital to accelerating this current and essential clean-energy transition.