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Are Generation IV nuclear reactors the answer to green energy?

Dr. Edward A. Friedman is an emeritus professor at Stevens, meaning he doesn’t have to teach. But he does anyway. “Nuclear Energy and Society” is a course he built on the conviction that “nuclear energy, terrorism, and weapons are more important than they have ever been. Yet people — students — know less about them than they used to.”

This was the angle he took in a talk for the MIT Alumni Association this summer. There he mentioned a little-known, world-altering policy group: the Generation IV International Forum (GIF).

Since 2001, the forum has quietly gained the membership of 14 countries, including the United States and China. Each recognizes the world’s urgent need for sustainable nuclear energy. But they don’t want more of the same reactors we already have — reactors which inspire fear and memories of Chernobyl and Fukushima. They want new, Generation IV reactors.

Nuclear energy is controversial among politicians, environmental activists, and investors. But new reactor designs, the immense energy-density of nuclear fuel, and the lack of carbon emissions make nuclear power attractive, if not crucial, amid growing energy demands and a changing climate.

In the United States, around 100 nuclear reactors provide 20% of the energy. Worldwide, 449 reactors provide 10%. But the designs, dating back to the ’50s, are homogenous. Most reactors use water to cool the Uranium fuel and spit out weapons-grade Plutonium-239 as waste. In his talk, Dr. Friedman, who has physics degrees from MIT and Columbia, emphasized that there are in fact “more than 1,000 possibilities” for reactor designs. This estimate considers fuels, nuclear moderators, coolants, control rods, and the physical configuration of these components. From these possibilities come Generation IV reactor designs.

Generation IV reactors are breeder-burners, meaning the Plutonium-239 byproduct is never removed but simply recycled as fuel. This reduces problems of waste and weapons proliferation. Moreover, they are hands-off, built to go decades without refueling or human intervention. With modular construction, reactors should be cheaper to build. And, significantly, the designs explore alternate cooling systems.

Cooling errors leading to hydrogen explosions were responsible for all three nuclear power plant meltdowns in the past century: Three Mile Island in 1979, Chernobyl in 1986, and Fukushima in 2011. New cooling systems cut the risk of these meltdowns.

In his talk, Dr. Friedman advocated specifically for liquid sodium coolant. The idea has been around since the ’90s, with a paper co-authored by Edward Teller, “Completely Automated Nuclear Reactors for Long-Term Operation.” In a May 2018 Scientific American article, Dr. Friedman explains:

Sodium’s thermal properties provide far superior heat transfer than those of water (the water is pressurized, in fact, to improve heat transfer). It’s also a stable fluid that can be used at an operating temperature of 550 degrees Fahrenheit at ordinary atmospheric pressure, so there’s no need for an expensive containment structure. Pressurized water, by contrast, carries a danger of explosion.

The promise of liquid sodium coolant and other Generation IV features has inspired investors such as Bill Gates. In 2006, Gates began the firm TerraPower to design and build Generation IV nuclear reactors.

The question lingers, if this technology has been around for decades, why is it unpopular? Why hasn’t nuclear power taken off? The biggest reason is money. The price tag on a 1000 MWe nuclear reactor in the United States is $10 billion. But with modular designs and streamlined production, Dr. Friedman imagines that cost lowering to $1 billion (the U.S. Department of Defense’s yearly budget is $640 billion). Already, China and South Korea can produce reactors at a fraction of the cost that the United States can. Accounting for increased energy demand, Dr. Friedman estimates that 8,000 nuclear reactors are needed to power the world with zero emissions. That makes for an $8 trillion global investment. Note that the current world GDP is $60 trillion.

Another reason is risk perception. The three major accidents of the past four decades have instilled a fear of nuclear power among citizens and politicians. This led former president Bill Clinton in 1994 to shut down one of the most promising nuclear power plants in history, the Integral Fast Reactor, despite astonishingly good safety demonstrations.

According to psychologist Steven Pinker, fears of nuclear power are overblown. Consider oil and coal. According to an article co-authored by Pinker in The New York Times, “Even if we accepted recent claims that Soviet and international authorities covered up tens of thousands of Chernobyl deaths, the death toll from 60 years of nuclear power would still equal about one month of coal-related deaths.” And with new designs and simulation technology, the risk of nuclear power will only decrease.

Dr. Friedman is not idealistic about Generation IV reactors. In his Scientific American article, he admits there are still technicalities to work out. For instance, “the potential of sodium leaks leading to possible fires and explosions.” There is also the problem of keeping the fuel rod positioned for the full 50-year runtimes to avoid human intervention.

Still, we need nuclear. Friedman is an outspoken supporter. And Pinker and his co-authors argue that wind, solar, and water power are not enough. They cite insufficient battery technology, weather issues, and that “the world’s best hydro sites are already dammed.” Nuclear power, though, is consistent, clean, and, well, powerful.

As I sat with Dr. Friedman after one class, he lamented that Bill Gates’ TerraPower has stalled, having relied on help from the China National Nuclear Corporation. Nuclear power is an international undertaking, which, unfortunately, a poorly-timed trade war can interrupt.

But there is hope in Washington. In January, both houses of Congress passed the Nuclear Energy Innovation and Modernization Act (2019) to rekindle nuclear energy research. In March, Senator Lisa Murkowski (R-AK) introduced the Nuclear Energy Leadership Act. The bill has bipartisan support.

“With presidential candidates Andrew Yang, Cory Booker, and Joe Biden including investment in nuclear R&D in their policy statements, I am optimistic that the pros and cons of nuclear energy will be constructively addressed as we approach the 2020 election,” said Dr. Friedman.

Meanwhile, the emeritus professor continues to educate on this topic of grave importance to us all.

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