Several weeks ago Joshua Pearce at Clarion University in Pennsylvania released a study titled “ Thermodynamic limitations to nuclear energy deployment as a greenhouse gas mitigation technology .” In the study he stated... nuclear energy production would have to increase by 10.5% per year from 2010 to 2050 to both replace fossil-fuel-energy use and meet the future energy demands. This line, of course, made the headlines and has been picked up by several outlets and blogs . When looking into his calculations for this statement, he made one assumption error that overstated the above sentence by nearly a factor of three. Page 121, Section 4.1 of the study states: Richard Smalley pointed out that in 2004, the global economy consumed the equivalent of 220 million barrels of oil per day, which converted into electricity terms is the equivalent of 14.5 TeraWatts (TW), or 14,500,000 MegaWatts (MW) (2005). … With a nuclear plant having about 1000 MW (1 GW) of capacity, we would need 14,500...
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One point that I wish Dr. Bonometti had discussed is an implication of the extraordinary level of safety of the LFTR: that it could be located close enough to large population centers to provide district heating and cooling (via the ammonia absorption cycle) from the ~50% of heat normally wasted by any type of plant sited in the hinterlands. Such a cogeneration, or combined heat and power plant fueled mainly by waste wood but partially by natural gas provides downtown St. Paul, MN with heated and chilled water via underground insulated pipes (it also sells electricity to the grid). Similar plants are common in Europe, especially so in Denmark where they have substantially reduced the use of oil and natural gas for heating/cooling.
High capital cost, low fuel cost power plants (nuclear and to some extent waste wood-fired biomass) need to be operated 24/7 at 100% power as much as possible to reduce the capital component of the cost of a unit of electricity to its minimum. Comparatively, high fuel cost, low capital cost power plants (oil, natural gas and coal in decreasing order of fuel cost) need to be operated as little as possible to reduce the fuel component of the cost of a unit of electricity to its minimum. In a rational world, nuclear plants supplemented by coal plants would provide the base load and some portion of daily cycling and natural gas-fired plants, rooftop photovoltaic (eventually) and wind turbines would handle the relatively small amount of remaining demand (peaking). Biomass is a niche player, but well-suited for base load. Therefore a city's relatively constant demand profile for heating/cooling/electricity is more closely matched by the economic operation profile of nuclear (&coal) plants than by that of the other plants. An advantage of the LFTR over other reactor types is that daily power cycling would be a snap as there is essentially no Xenon poisoning and the fuel is liquid so there would be no concern about power changes damaging fuel cladding. This LFTR advantage would reduce somewhat the need for higher fuel cost plants (e.g., coal) for daily cycling but would not diminish the need for peaking plants.
Don't get uptight just because someone pronounces one of the other correct ways.
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Back when atomic energy was the stuff of science fiction, the writers usually picked thorium as the fuel, it seemed the most logical choice.
What would prevent you from heating the material to 800C, then piping it into an electric furnace for that extra 150C of heating. The electric furnace can be powered from the waste heat of the reactor.
Seems a lot easier (and safer) than trying to get the whole reactor to work at 950C, although less efficient. It would also allow you to throttle the electrical output of the plant by controlling how much H2 was being generated at the moment, something that Nukes are normally quite bad at.
Expect that the anti-nuke Luddites will be unimpressed with MSR technology. It will still produce waste and, worse from their perspective, it reprocesses its fuel. The production of nuclear fuel (by breeding or otherwise) is evil unless it is being done by the Islamic Republic of Iran.
Nuclear reactions depend on nuclear fuel density. If the fuel density drops then the reaction stops. In the LFTR, the molten salt expands as it gets hot. If it gets too hot, it expands too much and the reaction stops.