See the papers by Hannum, Marsh, and Stanford and Baurac linked below. See the references in my long paper about energy and nuclear power. Read the UNSCEAR reports on Chernobyl and Fukushima linked below.
For a completely closed system that produces no long-lived transuranics, a fast-neutron reactor with fuel reprocessing, such as described by Till and Chang, is necessary.
We will need liquid hydrocarbon fuels indefinitely for airplanes, probably for ships, heavy construction equipment, farm equipment, and heavy freight too large for trains, and maybe for long-distance auto travel. In CO2 extraction from seawater using bipolar membrane electrodialysis (Energy & Environmental Science 2012, DOI 10.1039/c2ee03393c), Eisamen et al described the PARC BPMED process to extract 52% of dissolved CO2 from seawater at an energy cost of 242 kJ/mol (about 1.5 MWh/T). Hydrocarbon fuels can be made using CO2, hydrogen extracted from seawater using the copper-chlorine thermochemical process at an energy cost of 532 kJ/mol (about 0.079 MWh/T), and the Fischer-Tropsch process to combine them. PARC estimates this can be done for $3.00/gallon. The energy density of automotive gasoline is about 12.5 MWh/T. Burning hydrocarbon fuels made from seawater would be a net negative CO2 transfer to the atmosphere and oceans. CO2 that results from burning the fuels will go into the atmosphere, and eventually back into the oceans, but surely some will be trapped in plants and soils.
Uranium can be extracted from seawater, but this will not be necessary for a very long time. The United States has 80,000 tonnes of spent fuel and 900,000 tonnes of depleted uranium. This is enough to fuel an all-nuclear all-electric American energy economy for 575 years -- longer than that to the extent solar and wind contribute. The long term attraction is that it is essentially limitless. Uranium salts are water soluble, and are continuously entering the oceans from the bottom and in rivers. The concentration of uranium in seawater and ocean-bottom rocks is in equilibrium. As uranium is taken from seawater, more enters from rocks. There is enough uranium already in the oceans to provide all the energy humanity currently uses for a million years.
Essential reading if you want a deeper understanding of the way a fast-neutron reactor creates more fuel than it consumes, why the Argonne design is inherently safe (and read David Baurac's article linked below), how it works with pyroelectric refining to destroy nuclear waste, and why nuclear power, especially using this process, is irrelevant to weapons proliferation.
"Imagine a nuclear power plant so safe that even the worst emergencies would not damage the core or release radioactivity. And imagine that this is achieved not with specially engineered emergency systems, but through the laws of nature and behavior inherent in the reactor's materials and design...."
Nuclear power is "the energy source that can save our planet from another possible disaster: catastrophic climate change.... Nuclear energy is the only large-scale, cost-effective energy source that can reduce these emissions [of CO2] while continuing to satisfy a growing demand for power...."
The Soviet Union had no safety culture and no licensing criteria. The Chernobyl reactor should never have been built. It would not have been licensed in any other country. The fire is as relevant to other nuclear reactors as the crash of the Hindenburg is to a Boeing 777 or Airbus 380. But here's what the UNSCEAR report said about it:
134 plant operators and emergency responders at Chernobyl were exposed to sufficient radiation to develop acute radiation syndrome, which caused 28 deaths. Two others died from injuries not caused by radiation (falling debris), one from coronary thrombosis, and three in a helicopter crash. I don't count those six as "nuclear related." Fifteen excess cases of fatal thyroid cancer, compared to earlier decades, out of 6,000 cases reported between 1991 and 2005, were attributed to the accident. The report noted there is
"no scientific means to determine whether a particular cancer in a particular individual was or was not caused by radiation... [there is] no scientific evidence of increases in overall cancer incidence or mortality rates or in rates of non-malignant disorders that could be related to radiation exposure."
In the most affected regions (northwestern Ukraine, Belarus, and southwestern Russia) the average additional radiation dose to the general public over the period 1986-2005 was about nine millisieverts (mSv), or 0.45 mSv/yr. The report notes that residents
"need not live in fear of serious health consequences."
"Japanese people receive an effective dose of radiation from normally occurring sources of, on average, about 2.1 mSv annually and a total of about 170 mSv over their lifetimes.... No radiation-related deaths or acute diseases have been observed among the workers or general public exposed to radiation from the accident.... For adults in Fukushima Prefecture, the Committee estimates [the increase in] average lifetime effective dose to be of the order of 10 mSv or less... discernible increase in cancer incidence in this population that could be attributed to radiation exposure from the accident is not expected."
The dose from one abdominal and pelvic CT scan with and without contrast is about 30 mSv. The annual dose on the Tibetan plateau is 13-20 mSv. The X-ray dose to treat prostate cancer is 72 Sieverts (not mSv) delivered over a period of 56 days.
Tokyo Electric Power Company (TEPCO) was ordered to shut down the aging Fukushima reactors eight years before the earthquake. They got permission to keep them open provided they sought advice from the US Nuclear Regulatory Commission (NRC). They sought advice but ignored it. NRC advised them to move the backup generators out of the basement to high ground, and to bury the fuel tanks on high ground rather than leaving them on stilts on the beach. The tsunami washed away the fuel tanks and filled the basement with mud.
The incompetent and mostly unnecessary evacuation of 150,000 residents of Fukushima resulted in 1,500 deaths. For most residents, the advice should have been shelter in place. TEPCO employees were prosecuted for removing hospital patients from life support to prevent the one-in-a-billion chance of exposure to sufficient radiation to cause illness. The dirt in Fukushima is half as radioactive as the dirt in Denver. Residents could safely return to their homes. Instead, seven years later, thousands are living as refugees.
"While many modelled scenarios have been published claiming to show that a 100%
renewable electricity system [that excludes nuclear power] is achievable, there
is no empirical or historical evidence that demonstrates that such systems are
in fact feasible."
Publisher's link: http://www.sciencedirect.com/science/article/pii/S1364032117304495 (requests a fee)
Free link: http://www.thesciencecouncil.com/images/pdfs/Burden%20of%20Proof.pdf
"Preventing nuclear plant retirements is a cost-effective carbon avoidance strategy. The premature retirement of U.S. nuclear power plants could eliminate some of the benefits of proposed carbon regulations."
"When an operating nuclear plant shuts down, a big chunk of carbon-free energy is lost. A big chunk. There's just no way to spin that as a good thing. The five nuclear plants shut down between 2013 and 2016 alone produced as much electricity as all US solar put together. Carbon-wise, that means the next doubling of US solar will mostly be spent trying to make up for nuclear losses."
"The utopian ambition for variable renewable energy is to convert it into uniform firm capacity using energy storage. Here we present an analysis of actual UK wind and solar generation for the whole of 2016 at 30 minute resolution and calculate the grid-scale storage requirement. In order to deliver 4.6 GW uniform and firm RE [renewable energy] supply throughout the year, from 26 GW of installed capacity, requires 1.8 TWh of storage. We show that this is both thermodynamically and economically implausible to implement with current technology."