Nuclear

  • As of 2010, nuclear provides 19.6% of electricity in the United States, expected 17.1% by 2035 EEI, 39

Controversy

The appeal of nuclear is that it promises huge quantities of energy– enough to feasibly provide a complete replacement to the energy generated by burning fossil fuels (something that solar/wind do not offer in the foreseeable future).

The key drawbacks vary based on perspective. One major issue is the disastrous consequences of meltdown, which we've seen a few times globally (notably, Fukushima's recent disaster was particularly frightening since it occurred in a country with a reputation for advanced technology).

Another major problem is the disposal of the nuclear waste. The volume of nuclear waste is currently not enormous, but we also don't have any real safe disposal methods– so it's not sustainable in the long run.

Finally, nuclear plants have historically been slow and expensive to build. This is partly because regulations have increased drastically during nuclear build periods, requiring changes to construction plans mid-project. But opponents of nuclear are wary of the time it takes to get plants online– it doesn't get us off of fossil fuels on a short timescale after all if the construction projects bog down for 10-30 years.

This may all be a moot point with the growing use of natural gas making nuclear power plants economically unfeasible. It seems much more likely that natural gas plants will displace coal and nuclear just on a cost basis. Natural gas, of course, has its own controversies - see the natural gas section.

Position: anti-nuclear

  • New nuclear plants cost $0.25 per kWh. Compared to efficiency solutions and other renewables, this is too expensive (wind in a good site: $0.03/kWh, solar on a good day: $0.12/kWh) Lovins, 84
  • Reductions in carbon emissions need to take place on the scale of one to two years; it takes 10 years to get a new nuclear plant online (not including permitting/bureaucracy) Lovins, 84
  • Replacing the world's coal plants with nuclear plants increases the accessibility of raw materials for nuclear bombs globally Lovins, 84
  • Nuclear power plants require a lot of water; climate change causes droughts. This will increase operational expenses to unsustainable levels (and already has at some now-closed sites) Lovins, 85
  • There is no solution in place for safe disposal of radioactive waste from nuclear power plants Lovins, 85
  • Used nuclear fuel is up to a million times more radioactive than when it was fresh. It is mutated into isotopes of plutonium and americum as it decays Weisman, 210
  • Fossil fuels in large quantity are burned to mine, transport, and enrich uranium, as well as in the 10-19 years it takes to build a new plant Klein, 125

Position: pro-nuclear

  • Nearly one hundred nuclear facilities in 30 states provide nearly 20 percent of all U.S. electricity. NEI
  • Nuclear energy facilities are used at high capacity compared to other energy generation mechanisms. They operate at a 92% energy capacity factor, compared to 47.8% for natural gas, 60.9% for coal, and 33.9% for wind. NEI (though - is this a meaningful statistic? Doesn't seem useful to me)
  • One uranium fuel pellet creates as much energy as one ton of coal or 17,000 cubic feet of natural gas. NEI
  • Significant uranium resources are available from U.S. sources or friendly trading partners such as Canada and Australia. NEI
  • A nuclear energy facility’s life-cycle carbon emissions—including mining and producing fuel and construction of the plant—are among the lowest of any electricity generation source at 13 tons of carbon dioxide equivalent per gigawatt-hour, comparable to geothermal (15 tons) and wind (12 tons). NEI
  • All U.S. nuclear energy facilities have extensive environmental monitoring programs, which are under the oversight of the NRC and state regulators. NEI
  • Nuclear fission complements renewable sources in a long term energy strategy because it is reliable and high-load, compared to solar, wind, etc.'s fluctuating low to moderate loads Smil, 40
  • “Nuclear generation is the only low-carbon-footprint option that is readily available on a gigawatt-level scale. That is why nuclear power should be part of any serious attempt to reduce the rate of global warming; at the same time, it would be naive to think that it could be (as some suggest) the single most effective component of this challenge during the next ten to thirty years. The best hope is for it to offer a modest contribution. “ Smil, 43
  • Nuclear power has a significantly lower carbon footprint (accounting for full lifecycle) than either of solar or wind Cravens, 13
  • Coal plants cause more radiation dosage to their surrounding areas than nuclear plants Cravens

Myth debunking and understanding disaster

  • In a reactivity accident, the force created is more comparable to a TNT explosion than to a nuclear bomb (20 million times weaker than a nuclear bomb). Chernobyl is an example– in photographs you can see that the reactor building exploded, but not even the rest of the facility. Muller, 13-14
  • Fukushima's meltdown was caused by a failure of design requirements: engineering design assumed that grid power would be restorable within 8 hours of a failure, which would allow the continued functioning of cooling pumps when the power failed at the site. This assumption was proven false; the tsunami wrecked the surrounding infrastructure and caused a station blackout failure. The reactor shut itself off as designed, but radioactive material uncooled in the core caused the upper building at Fukushima to explode. More modern reactors cool passively and do not depend on auxiliary pumps. Muller, 14-15
  • Overheat can cause the metal capsules containing reactive material and waste to melt. This releases radioactivity and volatile gases. The most dangerous gases are radioactive forms of iodine and cesium. Iodine decays rapidly (8 day half-life). If inhaled, it accumulates in the thyroid and causes cancer there. This can be prevented with sodium iodide pills which saturate the thyroid prior to buildup. Cesium and strontium (30-year half-life) can concentrate in bones through direct consumption or indirect e.g. milk from cows which have eaten contaminated grass. Buildup is preventable by banning local crop consumption– not practiced for Chernobyl, but in place at Fukushima. Muller, 15-17
  • No Fukushima workers received enough radiation to contract radiation illness Muller, 17
  • A dose of 25 rem increases your likelihood of cancer by 1% scaled linearly Muller, 17 //TODO: Check this, I believe the science is not settled on whether small doses of radiation scale linearly in effect
  • The average rate of cancer contraction without exposure to nuclear is about 20%. Of 100k survivors of Hiroshima & Nagasaki, 20,000 die of cancer, but only about 800 die from cancer caused by nuclear radiation Muller, 19
  • Denver, Colorado is naturally radioactive (due to uranium deposits in granite); residents are dosed with 0.3 rem above usual annually. Despite this, Denver has a relatively low incidence of cancer. The ICRP recommends evacuation from a site with 0.1 rem annually, theoretically based on the precautionary principle– but Denver's example suggests this may be a misguided policy choice Muller, 20-21
  • Myth of uranium scarcity: we have enough uranium to last 9,000 years– it's cheaply recoverable uranium that is scarce, but this will still not be a primary expenditure for nuclear power Muller, 180

Mechanism

  • Current nuclear (fission) power works by creating heat through controlled atomic reactions, using this to boil water and create steam to drive a turbine. Specifically, all current nuclear plants use moveable cadmium rods to dampen or intensify the reaction (the rods suck up neutrons). Weisman, 209
  • Biggest nuclear plant in the United States: Palo Verde Nuclear Generating Station, west of Phoenix. Produces 3.8 billion watts Weisman, 209
  • Mechanism at Palo Verde: Cadmium dampers are interspersed with 170,000 cm-ish thick 14' hollow rods made of zirconium alloy stuffed with uranium pellets. Each rod contains the same amount of energy as 1 ton coal. Water flows through the rod assemblies to be heated. Weisman, 210
  • The volume of used nuclear fuel rods created over the past 40 years is 74,258 metric tons. That's one football field, 8 yards deep. NEI
  • Nuclear plant capacity factor is at around 90% Muller, 184
  • A "nuclear battery" is a small, self-regulating source of nuclear power, often buried for 5-30 years of operation (at which point it is typically exhumed and refueled). Self-regulation is based on physics rather than engineering principles– there are no moving parts; neutron reflection and convection moderate the reaction. Muller, 186-190
  • Waste storage: uranium is mined from underground; if not mined, it could leak radiation into the water table– this gives us a baseline safety for storage. Nuclear waste is 100x more radioactive than raw uranium after being stored for 100 years. If you can design storage that has a <10% chance of leaking <10% of the material after 100 years, you have decreased global danger from uranium-based radioactivity after using that uranium to produce nuclear power Muller, 196

Economic viability

  • Building a nuclear energy plant is very, very slow and expensive. Between 1972 and 1992, the cost of building a new 1 GW nuclear power plant in the United States increased more than 10x. This was due mostly to increased safety regulations. The plants are now much less likely to become meltdown sites, but the adoption rate is very slow. Smil, 36
  • Viability of financing for nuclear– new, extended, or uprated– is somewhat competitive with natural gas for economic viability. There's a strong possibility that natural gas electricity is so cheap that nuclear plants will go offline in the near future EIA, 113
  • Small (300 MW) modular nuclear plants are less of a capital risk than traditional 1 GW models and can be expanded later by adding more modules to existing grid-hookup infrastructure. Because selling nuclear power is profitable, this means smaller financing deals can start modular nuclear plants which then pay for their own expansion up to & beyond the capacity of older, large plant designs Muller, 186

Research efforts

  • Nuclear research received 96% of all funds appropriated by the US Congress for energy-related R&D between 1947 and 1998, a total of $145b in 1998 dollars Smil, 43
  • LMFBRs are intended to increase the supply of consumable reactants by converting a more available nonfissionable uranium isotope to a fissile plutonium isotope in a reaction less energy expensive than the energy retrieved from the result. Experimentation in this area (a fission reaction) has been funded and active since the 40s with no promising commercial outcomes yet Smil, 38-39

Fusion

  • Fusion reaction: combine deuterium and tritium to make helium and a radioactive neutron Muller, 200
  • "Breakeven fusion": nuclear fusion that produces more energy than it takes to create the reaction– has not yet been achieved
  • Tokamak: toroidal chamber with magnetic coils based on thermonuclear fusion (high temp hydrogen fusion as in the sun or a hydrogen bomb). In Tokamak reaction, magnetic confinement holds hydrogen with a magnetic field so it can be contained at the extreme temperatures of a reaction. This is the key challenge in Tokamak, there's progress but it still leaks Muller, 202
  • Beam fusion: as opposed to thermonuclear, not based on heat. Collide enough density of atoms in neutron generators (beams of deuterium) into a tritium target– NIF is a research site Muller, 208

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