Nuclear energy is amazing. It is mostly produced from the chemical element uranium. A one-kilogram piece of uranium (a cube about 1.5 inches per side) has as much energy content as 20 metric tons of coal. It is the largest source of clean energy in the United States, accounting for about half of all our low-carbon energy. Even accounting for a history of nuclear accidents, it is one of the safest sources of energy at about 0.03 deaths per terawatt-hour, or more than 800 times safer than coal energy. And it is one of our cheapest fuel sources, at about 71 cents per million British thermal units, which is about a tenth of the cost of natural gas last year. So why aren’t we using more of it? The answer is that the economics are more complex than they initially seem.

Nuclear power has been around in commercial form since the 1950s, and most of the nuclear power plants (NPPs) in operation have been around for decades. In fact, the oldest NPP in use today was initially constructed in 1969. When nuclear power was first getting its legs, the promise was that it would make electricity “too cheap to meter,” since uranium is so inexpensive, abundant and energy-dense that it was expected to effectively solve energy scarcity. But nuclear power has two key challenges that are intertwined: capital intensity and safety.

Even though uranium itself is a bit of a wonder fuel, accessing its energy content has historically required large, expensive reactors and facilities. The high cost of constructing these facilities means that even though uranium itself is cheap, it isn’t always economical to build. The Cato Institute examined the costs of building new nuclear power compared to other resources and found that in almost all cases it is more economical to build a natural gas facility.

Nuclear power, of course, also has safety challenges. Chernobyl, which occurred in 1986, was the largest nuclear disaster, resulting from a pressure build-up in the reactor causing a conventional explosion that dispersed radioactive debris and dust over a massive area. Since uranium for nuclear power is never enriched to a concentration that could produce a nuclear explosion, Chernobyl represents pretty much the worst imaginable scenario, and there is significant debate as to the death toll. At one point the death toll was estimated to be a total of 4,000, but these estimates assumed that radiation exposure would lead to cancer and mortality. Studies conducted years after the accident found no elevation in cancer rates that could be attributed to radiation exposure, and more recent estimates place the death toll at a maximum of 300 to 500, with less than 100 confirmed deaths attributable to the incident. The loss of life from the Chernobyl incident was tragic and avoidable, particularly thyroid cancer in children from drinking contaminated milk, but even with such hazards, nuclear power is far safer than other forms of power.

Chernobyl is a major outlier in the history of nuclear disasters, and no U.S. power plants utilize Chernobyl’s faulty power plant design. The second-largest nuclear disaster was in Fukushima, and there is an estimated one death directly attributable to radiation exposure. The largest nuclear incident in the United States, Three Mile Island, had no fatalities or injuries.

But even if these incidents have comparably low mortality, their risk is still high, and the policy solution is typically regulation. Because there is no tolerance for failure with nuclear power, the opportunity for markets to temper the economics of NPPs is limited. Additionally, after the Sept. 11 attacks, NPPs faced an additional burden to guarantee security. Because of the importance of nuclear safety, there is almost always a demand for more regulation and the associated costs climb, and building new nuclear power becomes more and more expensive.

A new set of reactors were built in Georgia recently, which is remarkable because the United States mostly stopped building nuclear power plants in the 1990s, and these reactors were expected to cost $14 billion but ended up costing nearly $35 billion. Aside from cost overruns, there are challenges with nuclear waste storage, and the industry has relied on subsidized insurance and credits to keep reactors online in the face of lower cost renewables and natural gas. Conventional nuclear power has, in a word, struggled.

There is a big hope, though, for advanced nuclear power, which is thousands of times safer than our already safe existing nuclear power and could theoretically avoid many of the constraints that make it so difficult to build and site NPPs in the United States. These advanced reactors can also be smaller, making them economically attractive to big corporate energy consumers that want to supply their own power. But the Nuclear Regulatory Commission has been slow to implement the sort of changes that would make it possible to approve and build these advanced power plants, so while there is cause for optimism it has been tempered.

From a policy perspective, a lot of potential economic and environmental benefit is being left on the table from not using more nuclear power. Net-zero emission pathways almost always demand more nuclear power than is in use today. But the only way that is achieved is if nuclear power becomes cheaper, and that’s probably going to require changes to the way we regulate it. Even though experts believe that making it easier to build new nuclear would make nuclear safer, it isn’t a popular political position and hasn’t been a priority for politicians.

In the end, nuclear power is a great example of how even miraculous energy breakthroughs run up against challenging market dynamics and regulatory constraints. If we want more clean energy, we ought to be open to making it easier for innovation to get to market, not harder.

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