Wednesday, June 26, 2019

Open Letter to Democratic Candidates to Support Nuclear Power


The Washington Post recently published an informative article on all the candidates hoping to become the Democratic Presidential nominee in the 2020 elections.  This article focused on the issue of Climate Change, and I am pleased to note that all the candidates recognize the importance of the issue, the existential threat it poses to humanity, and the urgency of tackling this challenge.  I was particularly heartened that seven candidates (Bennet, Booker, Delaney, Hickenlooper, Moulton, Ryan, and Yang) support building more nuclear power plants.  I thank all of them for taking this position, as I do believe that nuclear power is the cleanest, safest, and most environmentally benign source of energy the world so desperately needs.

There are six candidates (Biden, Gillibrand, Harris, Klobuchar, O’Rourke, and Warren) whose have not made their position on this question clear. Of the remaining ten candidates, four are totally opposed to nuclear power (Gabbard, Messam, Sanders, and Williamson) and six oppose building new plants at this time (Bullock, Buttigieg, Castro, de Blasio, Inslee, and Swalwell).  I looked at the reasons the candidates offer for opposing expansion and development of nuclear power. They are safety, waste disposal, cost-effectiveness, and a belief that other technologies like wind, solar, and geothermal together with energy efficiency will suffice to meet our demands. I have previously written and spoken on these concerns but will summarize them here too. I will also show that there are serious consequences of not pursuing nuclear power. There are trade-offs with all energy systems, but the benefits from nuclear power far outweigh the risks.

1. Safety. There are several aspects of safety to be addressed. Most of the expressed concerns are based on unsubstantiated claims and misunderstandings. Often people conflate nuclear weapons with nuclear power and think of a nuclear power plant exploding like a nuclear weapon. That is simply not possible. The uranium in the fuel rod is typically enriched to about 4% of the 235U, while a nuclear explosion requires enrichment in excess of 80%. Nor is the fuel in the power plant in a configuration to sustain a nuclear explosion. What about the explosions at Chernobyl or Fukushima, you might ask? They were chemical explosions, and thus orders of magnitude weaker than any nuclear explosion. What happened was that steam came in contact with hot metal and produced hydrogen gas. The gas accumulated in the building and then explosively combined with oxygen in air. The power of the explosion was sufficient to blow apart the structure and led to the release of radioactive materials and raises legitimate safety concerns. These events are extremely rare.

Health risks from radiation are also widely misunderstood. No one denies that acute exposure to high levels of radiation, however rare, are fatal. The level of exposure is commonly measured in units of sieverts (Sv), which take into account the energy of the radiation and the nature of the tissue. Acute radiation of 3 to 5 Sv is fatal to humans. However, radiation therapy often entails exposures between 20 and 40 Sv spread over a month or so. Of course, the rest of the body also gets some exposure, but the doctors manage that exposure to levels that may cause hair loss or radiation sickness, but not be fatal to the individual.

There is a myth that any exposure to radiation is harmful. This is simply not true. We are constantly exposed to radiation from a variety of natural sources (e.g., cosmic rays, granite and other minerals, and radon gas) as well as during many routine medical tests (e.g., X-rays, CT-scans). It is true that radiation can damage our DNA and thus lead to cancer, and while it is one thing to expose a cancer patient to radiation for therapy, it is quite another to expose the general public to unnecessary radiation.

Out of an abundance of caution, the nuclear power industry and the regulatory bodies have for years adopted the “linear no-threshold” (LNT) hypothesis as the guiding principle that would minimize exposure. However, many anti-nuclear organizations have used this stance to drill the message that all radiation is harmful. According to LNT, it does not matter if one person is exposed to 5 Sv or 1000 persons are exposed to 5 mSv (millisieverts). That’s like saying that the effect of one person dropping off a 100-foot cliff is the same as 100 people jumping off a 1-foot step! LNT implies that our bodies have no repair mechanisms, which is also not true. Simply living on Earth typically exposes us to between 3 and 7 mSv/year, and cells have evolved in this environment by developing mechanisms for repairing DNA.

The LNT estimate of premature fatalities from long-term exposure to low levels of radiation on large populations leads to ridiculously large numbers. For example, radiation leakage from the worst nuclear accident at Chernobyl has been reported to potentially lead to 100,000 or more premature fatalities. The fact is that other than the 39 workers who went in immediately after the accident who died from acute radiation exposure, there have been very few additional cases of cancer. The UN body, UNSCEAR, that reports on radiation safety had previously estimated up to 4,000 additional cases, but in 2008 it issued a revised report stating that the estimate is too large, and it would be hard to detect

The downside of taking this extreme cautionary position is that we have instilled fear in the public, and second our response to nuclear accidents have caused real harm. Consider what happened at Fukushima. There was a massive earthquake followed by a tsunami resulting in the death of about 17,000 people. There was radiation leakage, but the amount of radiation posed risks to people in the immediate vicinity. The forced evacuation of over 200,000 people living within 20 miles of the plant caused much disruption and resulted in over 1,500 fatalities from mental anguish and interrupted health services. In contrast, no one died from radiation exposure. The workers who went in clean up were monitored to limit their exposures. One worker contracted cancer, and while the power company has assumed liability it is far from certain that radiation caused that cancer.

All power systems are associated with fatalities, and a lack of access to electrical power is also responsible for far too many premature deaths. There are tradeoffs to be made, and our decisions should be informed by data. The number of fatalities per unit of electrical power delivered is the lowest for nuclear. Thus, while on average coal power results in 160 premature deaths per TWh of power; I say on average because it greatly depends on the types of scrubbers and other emissions control measures that are put on the plant. Oil and gas power plants typically have 30 fatalities per TWh. Fatalities on the order of 0.1 per TWh result from wind and solar operations—both during the mining and processing of materials as well as during installation. In their 70-odd year history nuclear power plants have resulted in 0.0013 fatalities per TWh. It is by far the safest technology! And when countries replace nuclear power by installing natural gas or brown coal plants, they are increasing the number of premature deaths. By opposing the development of nuclear power, “environmental” organizations have perversely had the effect of promoting unsafe power systems.

2. Waste disposal is the second big issue for many opposing nuclear power plants. Despite the common misconception of nuclear power plant waste as a green liquid leaking out of drums and threatening water supplies, the “waste” from power plants consists of solid ceramic pellets in steel rods that are encased in dry concrete casts. I put quotes around waste, because it should be thought of as a resource for the next generation of reactors. More than 90% of original fissile and fissionable material is still in the fuel rods when they are taken out of service in the current light water reactors. Buildup of fission products interferes with the neutron balance and hence the spent fuel must either be reprocessed or burnt in what are called fast-reactors. Sure, the spent fuel is radioactive, and when it is first removed from the reactor, it has to be safely stored under 20 feet of water to cool the rods and provide adequate shielding from the radiation. After 10 years under water, the highly radioactive fission products in have decayed to a point that the rods may be stored on site in dry concrete casks with passive air cooling.

The total amount of spent fuels is tiny. According to the International Atomic Energy Agency, the total amount of spent fuel produced by all the nuclear power plants over the last 70 years is 370,000 tons. about 120,000 tons of it has been reprocessed, leaving 250,000 tons of spent fuel. Contrast this to the billions of tons of ash from coal power that is also toxic and radioactive, not to mention the billions of tons of carbon dioxide that are simply released to the atmosphere and are the principal cause of climate change. The total volume of all the spent fuel is 22,000 cubic meters, which would fill one football field (100 yards by 55 yds) to a depth of 13 feet!

High cost of nuclear power is also given as a reason to oppose it. Nuclear power plants are costly to build, but they are built to last a long time—60 or more years instead of the 20-30 life time of wind and solar installations. Also, once built they produce electricity consistently over 90% of the time; the occasional downtime being for fuel changing or servicing. Contrast that with the intermittency of wind and solar that generate electricity only around 25% of the time. The low capacity factor 25% for renewables means that in order to obtain the amount of electricity generated by a nuclear plant in a year, you have to install three times as many MW of wind and solar plants. On top of that, you will have to build a comparable amount of storage capacity if the renewables are to be the primary source of electricity. The cost of storage is not included when proponents cite the falling the price of renewable power, which currently depends on the extant grid for storage. Renewables are often backed with natural gas peaker plants to provide the power in case the wind doesn’t blow or the sun doesn’t shine.

Because the amount of renewable power currently comprises less than 15% of the electricity, the grid can accommodate it, albeit with increasing difficulty. As the penetration of these renewable sources increases, they will require massive amounts of storage and a complex Rube Goldberg-like system to manage the mismatch between demand and supply due to variability and intermittency of these sources. Nuclear power plants may cost more initially, but over their lifetime they are less expensive than the alternatives.

The cost of construction of nuclear plants used to be about $2/W ($2 billion for GW plant) in the U.S. back in the 1970s. It has risen substantially to over $10/W, because we have not built any in decades. The new ones have been plagued by many mid-stream design changes, and these costs are not representative of what is achievable. Construction costs in countries like South Korea, China, and Russia are still around $2/W. The amount of materials required for nuclear power are about a tenth of what are needed for wind and solar plants. Thus, if we can standardize our power plants and start building already tested, safe, and reliable light-water plants, their costs will come down, and we will build a work force in the pipeline for the next generation of nuclear power plants that are walk-away safe and that could use the spent fuels as well as materials from nuclear weapons, which would be in essence beating swords into plowshares.

Many candidates have expressed that renewables alone can suffice to meet our energy demands, and hence there is no need to build nuclear power plants. This is a highly seductive notion, and it has been promoted by many in the environmental movement as well as by celebrities. People are also attracted to renewable power sources because they offer opportunity to employ millions of workers. But the objective of the energy industry is not to provide employment for people. It is to produce a commodity at an affordable cost that other businesses and industries can use to generate employment. The large number of “green jobs” is a reflection of the very low energy density of renewable sources, which also means that systems for harvesting wind or solar energy have to be very large. They require a lot of space and they consume a lot of materials for constructing power extraction devices—wind turbines or solar cells and the associated structures. Mining and extracting the required materials have large environmental footprint in addition to the vast areas that need to be devoted for wind and solar farms. Under the 100% renewables scenario, the global demand for commodities like concrete, steel, rare earths, copper, and aluminum will increase dramatically and strain their global supply chains. The renewable energy sources are far from being environmentally benign, and from an environmental perspective, nuclear power has the smallest footprint.

There is agreement among all the Democratic candidates that there is an urgency with which we must reduce greenhouse gas emissions if we are avoid the catastrophic effects of climate change. Countries that have successfully decarbonized their energy supplies, notably France and Sweden, have done so with nuclear power as the backbone. Germany tried to decarbonize through their Energiewende program, but once they turned off their nuclear plants in 2011, their emissions have largely held steady or slightly grown; and Germans pay among the highest cost for their electricity.

My plea to the candidates is that they approach the 2020 elections with the clarity of a 20/20 vision. I urge you to look at the facts about nuclear energy dispassionately and support its deployment and development. Again, thank you to all who have already expressed their support for nuclear energy, and I hope this piece helps convince the others—particularly those on the fence—to come out and express their support.

Our need for clean electricity is huge, and more so as we electrify our transportation system and install new cloud servers to support e-commerce. We are in a hole! Let’s stop digging us deeper by shutting down well-functioning nuclear power plants. Let’s not wait for advanced next-generation nuclear plants but continue to replicate the ones that we know have a proven track record of safety. When the advanced reactors are ready and the Nuclear Regulatory Commission has blessed their designs, we can start manufacturing them, but the urgency demands that we make the transition to zero-emission sources as quickly as possible, and that requires nuclear power.

Good luck to all of you in your campaign!