Bill forgot the only thing that can truly be a game changer: Nuclear Fusion. In the long run, this is the only solution that can provide the amount of energy required by our modern society.
Ja, called sun. Already an off-earth installation available. Transfer of energy via radiation. Has just to be collected and transformed to electricity.
Nuclear fusion and fission are both exceptionally complicated ways to boil water, and even if given an ideal water boiler, turbine and cooling plants still need to be built for them and situated somewhere that about 3 times as much heat energy can be released into the local environment. This is known as thermal pollution:
"ultimately, when heat waves are extreme enough, power plants will need to draw down their power output."[1]
Here [2] is a study which shows anthropogenic heat emissions from energy consumption are a pressure on global climate. If we put out another 200%+ of whatever energy we consume, in the form of thermoelectric cooling (heat) then quite surely that will amount to a bigger problem.
Also,
"Thermoelectric power use has a significant impact on water resources and the power sector is highly dependent on these water resources; the United States Geological Survey (USGS) estimated on a national level that 41% OF ALL FRESHWATER WITHDRAWALS in the United States in 2005 were for thermoelectric power operations, primarily for cooling needs (Kenny et al 2009)."[3]
I believe the real game changers are plainly solar and wind. These have shown the most rapid improvements from investment. On similar timescale to developing fission or secure nuclear, floating oceanic wind and solar combined with hydrogen generation rigs (and even ocean plastic filtering) are possible...
Also, your estimation is incorrect. The thremal rated power of a nuclear reactor doesn't mean it releases 3x as much heat in the environment. At least 1/3 of the thermal energy is converted to electricity, and part of what remains is fed into a new cycle. The overall efficiency of a nuclear reacor is 33-37%. Gen IV reactor projected efficiencies are above 45%.
Waste heat cant simply be used for this and that, or else we would see all existing thermo-electric powerplants already doing so. Efforts to make thermo-electric plant more efficient and use waste heat are ongoing, but full use of waste heat would be a more game changing development than practical fission reactors !
Its rather rhetorical for us to quibble with my statement "about 3 times.." But in my readings on the matter 33-37% is the theoretic optimal running efficiency of most existing nuclear plants (depends on the kind and expense of turbine cycle and cooling system employed).
Combined heat and power (CHP) is a thing, though mostly in colder climates where there's a need for heating in the winter.
In principle you could do the same with nuclear, but there's challenges in siting a reactor close enough to a big city, and also current reactors tend to be too big. SMR's might help, and there's active research in this area.
SMRs likewise require generators and cooling plant, 2 or 3 times as much cooling as electricity produced, perhaps even more if its to be done most economically. So if CHP is justification for such release of heat into cool environments - they should be categorized as mainly a source of heating, not high value electrical energy. An ability to make continuous heat on this planet is not a futuristic energy supply in its own right, it falls well short of the "game changer" goal.
That's internal passive cooling which they mention briefly in their faq (transferal of heat from their reactor to their output loop). These units take in water and output steam, and they need attached to thermo-electric plant to produce electricity. They are water boilers.
I'm currently reading Griffith's Classical Electrodynamics and Jackson's Electrodynamics, coupled with lecture notes on plasma physics, in order to take a crack at the problem of nuclear fusion. Many other people are doing similar things, because it may possibly be the most important invention that anyone will ever create.
Oh, I don't mean that we should ignore fusion. We should invest in its research, probably as much as is helpful to speed it up. But when considering how to reduce greenhouse emissions right now, fusion is not an option.
I don't think so, not for the foreseeable future at least - fusion has to be cheaper than fission to be interesting, and fission is probably too expensive at the moment already.
No, solar is fine. Well, that's also fusion power in a way, but driven by an existing fusion reactor that doesn't cost us any energy. And for the next couple of centuries or millennia, it will continue to produce more energy that we'll ever need.
Nuclear fusion would certainly be nice if it could be made to work, but I've lost my enthusiasm about that a long time ago. Solar is giving us far better returns.
Very unlikely that fusion will have any impact on climate change on the timescale which is necessary. The cuts need to be made over the next 20 years, even if we had the technology, it would take a lot longer to scale up.
Not sure why only fusion power would allow that. Solar power is making use of energy that's already heating our planet without us making use of it. Turning solar radiation into electricity instead of heat, makes more efficient use of energy we already have without having to generate more of it from different sources, like fusion.
And the amount of sunlight we receive is enormous. If we could make use of a significant faction of that, it would provide more energy than we ever need. There's no reason that can't do anything that fusion power will ever be able to do on Earth.
The only real advantage fusion power has over solar is that it's independent of the sun and can be used in deep space. Well, once it finally works.
