MIT is also the origin of Transatomic Power which went belly up after they discovered that an early math mistake meant that their whole plan was bunkus, so evaluate this on its own merits rather than assigning any halo points from the MIT name.
MIT-designed project achieves major advance toward fusion energy
231–240 of 438 posts
Re: MIT-designed project achieves major advance toward fusion energy
#232Earlier quoted context omitted.
One of the big problems with existing power plants is that you have to build them near where people are. So then land is expensive and you get a bunch of regulations because people are worried about what's happening in their back yard. If you could hypothetically build a fusion plant that would generate several times more power than existing fission reactors at a similar construction cost, you would have so much powe…
How is that reasoning specific to fusion? Unless fusion power is dramatically more efficient than other thermal plants, like 99.9%, your bigger plant will still need massive heat removal structures and systems, which means siting them near water. All the good spots are already taken. Alternatively you can use truly massive air heat transfer structures, driving up your construction costs again. I neglected to mention…
> How is that reasoning specific to fusion?
A major cost of the most utilized existing power plants (coal and natural gas) is fuel. If you build a natural gas plant which is twice as big so that you can put it out where the land is cheaper and eat the transmission losses, now you need twice as much natural gas.
Renewables don't need fuel but their construction cost is fully linear, you get no economies of scale. If you want twice as many solar panels then you need twice as much land. If you want to double the size of your fusion reactor, you build an eight story building instead of a four story building on the same piece of land.
> Unless fusion power is dramatically more efficient than other thermal plants, like 99.9%, your bigger plant will still need massive heat removal structures and systems, which means siting them near water. All the good spots are already taken.
An obvious solution is to build them out in the ocean. Then you have plenty of water and you're still not near anything.
And the good spots near population centers are already taken. Some lake a hundred miles from any city won't be.
> I neglected to mention finance costs also. With an untried technology the rate of return demanded is going to be very high, further driving up project costs.
That's only true for the first one. If it's hypothetically ten times more power for the same money, that'll get one built even at a high interest rate. Then once you have it running it's proven technology.
Re: MIT-designed project achieves major advance toward fusion energy
#233Plenty of skepticism in these comments. I've been following CFS for a while and can present a point of view for why this time might be different. Fusion energy was actually making rapid progress in the latter half of the twentieth century, going from almost no power output in the fifties and sixties to a power output equal to 67% of input power with the JET reactor in 1997. By the eighties there was plenty of experim…
You are right, people who flippantly dismiss fusion just don't understand it. -Fusion has made consistent improvement, roughly in line with expectations for the level of investment (20 years away predictions were considering if we invested massively, which we did not). - Fusion is in theory something that could give us true energy abundance. Want to just desalinate water like crazy? Want to extract gigatons of carbon…
>You are right, people who flippantly dismiss fusion just don't understand it.
I have a couple of physics degrees, hot fusion is the energy of the future and it always will be. This is not a physics problem, this is an engineering problem and we are just not willing to invest enough money to solve the engineering.
Re: MIT-designed project achieves major advance toward fusion energy
#234Earlier quoted context omitted.
Yeah, really, how? Fusion power plants still need land, buildings, generators, switchyards, wire, own power consumption, environmental impact reports, planning permits, regulations, inspections, and all the rest. And they need exotic materials and weird engineering in their construction. Really: how does fusion get us to ~1% (correction: ~5%) of current power prices? I've never seen a convincing explanation. Usually…
Theoretically? Pure brute force. Fusion just generates that much electricity that it has the potential to be insanely profitable. There's a lot of ifs, but there's a good reason to bet big on it.
Please explain how it generates that much electricity that cheaply.
Direct conversion is theoretically about 60% thermally efficient, on par with combined cycle gas generators.
Re: MIT-designed project achieves major advance toward fusion energy
#235Earlier quoted context omitted.
Responding for the parent. They are basically making predictions with S curves. Technology often starts out as really expensive but after awhile gets super cheap, following what appears to be an exponential curve (bottom of the S), before it levels off (top of the S). Yeah, look more like an integral sign or sigmoid. But with fusion the endless claims of "too cheap to meter" are because how much energy there is in a…
If we got to the point where cost wasn't a factor would the carbon footprint be extremely low? I assume at some point we'll be unable to ignore climate change and our survival will depended on minimizing it using large amounts of energy from a source that doesn't have a high carbon footprint.
If only ~30% of CO2 emissions are from power-plants (at least in the US, probably higher globally considering developing nations) then replacing those installations with fusion won't directly zero things out...
... But if "cost wasn't a factor" then we could just simply dedicate the electrical output of fusion plants to brute-force CO2 out of the air.
Re: MIT-designed project achieves major advance toward fusion energy
#236Earlier quoted context omitted.
Is it really limitless if both generating and consuming energy produces heat? Or is that too small of an effect even despite the heat inefficiency of fusion?
Earth gets multiple orders of magnitude more heat from the Sun than humans can ever hope to generate. In concrete terms, Earths gets 153 PW of energy in terms of solar radiation. It also radiates as much. In comparison, humanity uses something like 20 TW in total (that includes not only electricity, but also transportation etc). So, we could increase our energy use 100 times, and still be only around 1% of what we ge…
So that's between 150 and 250 years with the 2.5% energy consumption grows, then that much again for us to produce more energy than the sun shines on Earth.
https://en.wikipedia.org/wiki/World_energy_supply_and_consum...
Re: MIT-designed project achieves major advance toward fusion energy
#237Earlier quoted context omitted.
Responding for the parent. They are basically making predictions with S curves. Technology often starts out as really expensive but after awhile gets super cheap, following what appears to be an exponential curve (bottom of the S), before it levels off (top of the S). Yeah, look more like an integral sign or sigmoid. But with fusion the endless claims of "too cheap to meter" are because how much energy there is in a…
If we got to the point where cost wasn't a factor would the carbon footprint be extremely low? I assume at some point we'll be unable to ignore climate change and our survival will depended on minimizing it using large amounts of energy from a source that doesn't have a high carbon footprint.
Yes. The reactor could more than pull out the carbon equivalent to its manufacture and then many many times more.
Re: MIT-designed project achieves major advance toward fusion energy
#238Question from a layman: how will the energy from a fusion reactor be extracted and converted into electrical energy? As far as I understand, the plasma inside a tokamak is isolated from the surroundings by the use of very powerful magnets. I assume in a reactor that is supposed to generate electricity there would be some interface between the plasma and some kind of heat exchanger that would generate steam and turn gas turbines?
Re: MIT-designed project achieves major advance toward fusion energy
#239I just read an article about this tonight on Sciencex.com I believe. It was impressive.
Re: MIT-designed project achieves major advance toward fusion energy
#240Earlier quoted context omitted.
Is it really limitless if both generating and consuming energy produces heat? Or is that too small of an effect even despite the heat inefficiency of fusion?
Earth gets multiple orders of magnitude more heat from the Sun than humans can ever hope to generate. In concrete terms, Earths gets 153 PW of energy in terms of solar radiation. It also radiates as much. In comparison, humanity uses something like 20 TW in total (that includes not only electricity, but also transportation etc). So, we could increase our energy use 100 times, and still be only around 1% of what we ge…
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