Energy Development and Slowing Climate Change
- Mar 5, 2013 3:00 am GMT
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Energy Development: The Race to Slow Anthropogenic Climate Change
We don’t really know how much trouble we are in with global warming, but if it continues experts tell us to expect flooding in coastal areas, intense storms, droughts, regional food and water shortages as glaciers disappear, mass migrations, and social upheaval. There is probably a tipping point, the point at which global warming becomes irreversible so there is an urgency to developing safe, clean, cheap energy. Scientists and engineers are in a race to find a solution. Currently in the U.S. we are seeing the replacement of coal with natural gas thanks to advancements in drilling technology and hydraulic fracturing. Although burning natural gas emits only half the CO2 that coal does, its emissions are still substantial and harmful. Natural gas will serve as a necessary intermediate step until something better comes along.
Wind and Solar
Wind and solar power might be a suitable alternative for energy in some places, but solar and wind will always be a small part of total energy production because of its high cost, and its low and intermittent energy output. A big windmill generates about five megawatts when the wind is blowing. A single coal, gas, or nuclear plant generates over 1,000 megawatts nonstop. Large solar installations generate from 50 to 100 megawatts when the sun is shining. Both wind and solar require fossil fuel plants to generate electricity at night or when the wind isn’t blowing. Germany is building 25 new coal burning plants for this purpose. Many locations simply don’t have enough wind or sunshine for wind or solar to be practical. The large land mass required by wind, solar, and required delivery grid is often met with resistance from locals who don’t want these industrial installations on their landscapes. Wind and solar are more expensive than coal or gas. Currently wind and solar are heavily subsidized by governments.
Nuclear power has the greatest potential to be the energy source of choice, but it has to overcome public and political resistance. Nuclear power has proven itself to be thousands of times safer than fossil fuels, just as commercial air travel is thousands of times safer than travel by automobile. We hear sensational stories about airplane crashes and nuclear accidents while tens of thousands of deaths from respiratory diseases caused by burning coal are ignored. Nuclear power has by far the lowest accident rate compared to coal, oil, or natural gas.
The only nation to suffer fatalities from a nuclear accident is Russia. Russian authorities report 31 fatalities from its1986 Chernobyl accident. UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiation) says that apart from increased thyroid cancers,* “there is no evidence of a major public health impact attributable to radiation exposure 20 years after the accident.” It should be noted that the Chernobyl plant was built without a containment dome and was run in a reckless manner. No Chernobyl type plants are in operation today. The Chernobyl plant was designed for making weapons, not electricity.
In the case of Fukushima the explosions and radiation did not and probably will not cause any deaths. The radiation levels most people experienced were 20 millisieverts or less. Cancers are not expected with exposures less than 100 millisieverts. The World Health Organization’s (WHO) report on Fukushima health risks says “for the general population inside and outside of Japan, the predicted risks are low and no observable increases in cancer rates above baseline rates are anticipated.” The greatest downside of the Fukisima accident is the overreaction of nations that have backed away from nuclear power and will increase the burning of fossil fuels to generate power. See Nuclear Safety in Wikipedia
Three Mile Island
Probably the most damaging overreaction to a nuclear accident was Three Mile Island; no fatalities, no injuries, no radiation exposure, yet the U.S. stopped building nuclear reactors for thirty years and built fossil fuel plants that added millions of tons of CO2 to the atmosphere.
For political reasons, the U.S. funding for nuclear power research has been shrinking steadily. This is due to two things: 1. fear of nuclear power and 2. an unfortunate choice made during the Nixon administration. The original purpose of nuclear power was to build bombs and power submarines. Using nuclear power to generate electricity was an afterthought. The design of nuclear power plants of those early days was the light-water reactor (LWR). This design has undergone significant design improvements, but it is still old technology that should be replaced with a better design. In the 1950’s and ’60s, after nuclear power from light-water reactors was well ensconced in its military role, scientists at Oak Ridge National Laboratory (ORNL) came up with another reactor design. The new design made meltdown impossible and the waste was a 1,000 times less than the LWR. In fact the new design could use the waste of the old design as fuel. The new design didn’t need large amounts of water the way the LWR does and could desalinate water while generating electricity. The new design didn’t even need uranium for fuel. A prototype was built and ran for five years to prove the design would work. It should be noted that the one thing the new design proved to be inferior at was making bombs. But that’s not surprising, it wasn’t designed for that.
When the Air Force came to ORNL scientists back in the late ’50s and asked them to develop a nuclear power plant for a bomber, the scientists were forced to create a reactor that was light, small, and safe. It would have to be one that would eliminate most of the problems of the LWR. The new design they came up with was the molten salt reactor (MSR). They built a small proof of concept reactor for the Air Force, but then funding was cut as long-range bombers were replaced with ICBMs. In the sixties ORNL received funding for the Molten Salt Reactor Experiment (MSRE). The scientists argued for continuing development of the molten salt reactor but the military and bureaucratic momentum were behind the LWR. The MSRE was highly successful and ran continuously from 1965 to 1969. A decision was made during the Nixon administration to stop funding for the MSRE in favor of development of a breeder reactor at a time when it was thought there was a shortage of uranium needed for LWR reactors. The breeder reactor ran from 1964 to 1994 when it was defunded. The breeder reactor design evolved to the Integral Breeder Reactor which is still being worked on today. The molten salt reactor work was forgotten. For 30 years students could get PhD’s in nuclear engineering without hearing anything about molten salt reactors.
Enter the 21st century and a young NASA scientist given the job of finding a way to power a colony on the moon. His name is Kirk Sorensen. He knew the power source would likely have to be nuclear given that the moon has no wind and two weeks of darkness every month, but the prevailing LWR designs all called for water, lots of water. One day while visiting a colleague’s office he noticed a book titled Molten Salt Reactors and asked to borrow it. He took it home and became consumed in its 1,000 pages of technical jargon and data. Kirk Sorensen was so enthralled with the design that he started a grassroots movement that today has scientists and engineers working on their own time to refine and develop the design. Their design is called the Liquid Fuel Thorium Reactor (LFTR), a type of molten salt reactor that burns thorium, a plentiful and cheap fuel.
The Generation 4 reactor design race
The race is now on to see who can produce the first commercial grade Gen 4 reactor and get international patents for it. The lead has been taken by China. There are over 100 companies in China working on designs for nuclear reactors, including the LFTR design. In fact, the LFTR design in China is receiving 100% Chinese government backing and the U.S. Department of Energy is cooperating with China by giving them all the research that was done at ORNL. The U.S. Dept. of Energy (DOE) describes this as collaboration. China stated clearly that it intends to be sole owner of any international patents on LFTR designs. At the time of this writing, there is no DOE funding for the development of LFTR’s in the U.S. Since Kirk Sorensen’s grassroots movement was initiated, many countries have begun R&D on molten salt reactors because the design is so promising and simple compared to other designs.
Meanwhile, Kirk Sorensen and a partner have started a private company called Flibe Energy, to develop LFTR’s. Ironically the U.S. Army is backing Sorensen’s efforts. Sorensen expects to have a LFTR power up in 2015. Kirk chose a partner in his company who is a lawyer and expert in international patents. He apparently sees the importance of getting those international patents before China does.
There are other nuclear designs in the works. Bill Gates is backing a nuclear reactor design called a Traveling Wave Reactor (TWR), a type of Integral Fast Reactor, that is being developed by Terrapower. Another company worth noting is Trans Atomic Power started by two MIT PhD students. Their design is a molten salt reactor they call Waste Annihilating Molten Salt Reactor (WAMSR) that will burn the nuclear waste produced by today’s LWR’s. They claim their idea is new but all LFTR fans know that molten salt reactors can burn nuclear waste. Nothing new about that, but good luck to them. I hope they end up joining Kirk Sorensen’s company, but there is no reason to think that will happen.
Robert Hargraves’ excellent book Thorium: energy cheaper than coal points out that LFTR’s could be built in factories and turned out at a rate comparable to Boeing’s production of airliners. LFTR’s could be used to power ocean going ships, a major source of CO2 , and could provide electric power for high speed rail to replace many commercial jet flights. The heat from LFTR’s could be used to synthesize hydrogen based fuels for automobiles, could be used to desalinate sea water in coastal areas, and could be used to bring energy to impoverished nations. Robert Hargraves makes a convincing case for the success of LFTR technology and its likely success in a capitalist economy. The only real question is whether the United States will be a leader or a follower in LFTR technology.
This is an important race worth watching. The winner is going to win big. We will all win big. Will we be buying reactors from China, or will Kirk Sorensen’s company prevail? In any case, clean energy is coming. I would just like to see Kirk Sorensen win the race. He deserves it. Without him, the Chinese wouldn’t even know about molten salt reactors. Moreover, as much as I would like to see Kirk Sorensen win the race, this is too important to be left solely to a small underfunded company. The DOE national labs need to be more involved. Currently the national labs are contributing in some important ways, namely research on materials that work best to contain molten salt for solar power plants. Their research will most likely be available to the private companies working on LFTR’s, but they should do more because they have the authority to build and test LFTR’s without the interference from the NRC.
Gen II and Gen III reactors are winners, but politics made us losers
While I am an advocate of the development of 4th generation nuclear power, it must be said that the political movement that has virtually stopped the building of nuclear reactors for the past thirty years is a disaster. Instead of using clean and safe nuclear power we’ve been building fossil fuel power plants and spewing millions of tons of CO2 and particulates into the air that have set us on a disaster course with global warming. That now appears to be changing. “Here in the United States, five new plants are expected to be operational by the end of the decade while internationally, 70 such facilities are planned.” reports Ken Silverstein in Forbes Magazine. Power Engineering Magazine reports Big Plans for Mini Reactors in February 2013 article.
Although Generation IV reactors should decrease worry about proliferation and disposal of nuclear waste, worry about today’s reactors is an unfortunate overreaction.
Proliferation risk: Current LWR reactors designed to generate electricity are not suitable for bomb building. If a nation wants to build a uranium bomb, enriching uranium to a high enough level for a bomb is much more difficult than enriching for a reactor. If a nation wants to build a plutonium bomb, the best way to do it is to build a different type of reactor for that purpose. In other words, it is simply not true that if a nation builds a nuclear power plant, it could easily build a bomb.** Nations make thoughtful decisions of what to build. They don’t say, “Oh, since we’ve built a nuclear power plant, let’s build a nuclear bomb too!” There are nations with nuclear power plants and no nuclear bomb, and there are nations with nuclear bombs and no nuclear power plants.
Nuclear waste: Nuclear waste is not a technical problem, it is a political problem. The U.S. could recycle its waste, but it makes more sense to store it and use it as fuel in 4th generation reactors. Yucca Mountain is an example of a technical solution being blocked by political problems. Current on site storage will suffice until the next generation of reactors come online. The next generation of reactors will burn nuclear waste from the old reactors.
** Uranium processed for electricity generation is not useable for weapons. The uranium used in power reactor fuel for electricity generation is typically enriched to about 3-4% of the isotope U-235, compared with weapons-grade which is over 90% U-235. For safeguards purposes uranium is deemed to be “highly enriched” when it reaches 20% U-235. Few countries possess the technological knowledge or the facilities to produce weapons-grade uranium.
Plutonium is produced in the reactor core from a proportion of the uranium fuel. Plutonium contained in spent fuel elements is typically about 60-70% Pu-239, compared with weapons-grade plutonium which is more than 93% Pu-239. Weapons-grade plutonium is not produced in commercial power reactors but in a “production” reactor operated with frequent fuel changes to produce low-burnup material with a high proportion of Pu-239.
The only use for “reactor grade” plutonium is as a nuclear fuel, after it is separated from the high-level wastes by reprocessing. It is not and has never been used for weapons, due to the relatively high rate of spontaneous fission and radiation from the heavier isotopes such as Pu-240 making any such attempted use fraught with great uncertainties.