I just read an article about this tonight on Sciencex.com I believe it was. It was impressive. It reached 20 teslas in their test.
MIT-designed project achieves major advance toward fusion energy
241–250 of 438 posts
Re: MIT-designed project achieves major advance toward fusion energy
#242Earlier quoted context omitted.
I'm wondering, fusion reactors themselves produce neutron radiation as a byproduct. Once you have a fusion reactor running, could you use the fusion reactor itself to breed tritium? Also thinking, we target deuterium + tritium fusion because it's the least energy intensive. However, once we have working proof of concept reactors, could we just make them slightly bigger and fuse more abundant molecules/isotopes instea…
While not listed in the article, this is the design goal of the SPARC reactor. Their plan is to use FLiBe (Google it) blanket to breed tritium. The Be acts as a neutron multiplier. As for non D-T fusion, the next best candidate is D-He3. Unfortunately, the only large scale source of He3 is on the surface of the moon and it would have to be mined, on the moon, and sent back to Earth.
A study on feasibility of lunar He3 mining https://ui.adsabs.harvard.edu/abs/2014cosp...40E1515K/abstra...
Not as bad as I expected but not yet feasible economic wise. Assuming the fusion part exists.
Re: MIT-designed project achieves major advance toward fusion energy
#243Earlier 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…
[deleted]
Re: MIT-designed project achieves major advance toward fusion energy
#244I just read this article tonight on Sciencex.com or .org. It was quite impressive. They reached 20 teslas in their test.
Re: MIT-designed project achieves major advance toward fusion energy
#245Earlier quoted context omitted.
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 y…
> A major cost of the most utilized existing power plants (coal and natural gas) is fuel.
Coal is dead. The competition is PV, and to a lesser extent wind.
> 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.
Yes, and you use odd bits of land close to consumption sites, many of which will have simultaneous use for other purposes. Edit: the linearity is an advantage in that it enables mass production, and gets the benefit of the manufacturing learning curve. So your suggestion of overbuilding on cheap land a long way away from cities applies even more to PV.
> 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.
Quadrupling your construction costs. Edit: mainly in the finance cost of the time taken.
Also, making your generators much bigger than current practise increases project risk and therfore cost.
> An obvious solution is to build them out in the ocean.
Quadrupling your construction costs again, and decreasing reliability, capacity factor and productive lifetime. Seawater is nasty stuff.
> And the good spots near population centers are already taken. Some big lake a hundred miles from any city won't be.
It will be used for productive farmland, though. Again, why aren't fission or CCGT plants being built in those places? How is fusion different?
> [High finance cost is] 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.
It's about time to cashflow for utility finance types, and they also tend to want a longer track record than "it worked once". The linearity/modularity of wind and PV is an advantage in the time to cashflow aspect.
Edit: I haven't so far seen anything significant in your replies that doesn't also apply to fission. Utilty project financiers are hard-headed; they'll finance fission if it makes them enough money soon enough.
You are fiddling around the edges rather than demonstrating an order of magnitude cost reduction from PV.
Re: MIT-designed project achieves major advance toward fusion energy
#246Earlier quoted context omitted.
SpaceX's main innovation was that they decided to build a rocket that wasn't optimized for performance or reliability, but cost. They were willing to bear huge development risks to create a new price category and capture latent demand for cheaper launches.
I'd say yes and no. You most definitely have a point here as I agree that their model, or view, is different than NASA. However, if NASA had not happened, would even conceiving of a different model or target had happened? Not to mention just initial research into rocketry. It maybe could have happened without NASA, but probably with a severely higher initial investment.
The soviets had a very strong space program and arguably their rocket designs have had a significant impact on spacex…
Re: MIT-designed project achieves major advance toward fusion energy
#247Earlier quoted context omitted.
You don't need an astroturf. Nuclear ruined it's own reputation for generations though hopeful not as long as they'll have to care for the waste we already have.
What ruined nuclear reputation is environmentalists who don't actually care for environment.
Parroting Shellenberger will never make you look like a serious participant in this discussion.
Re: MIT-designed project achieves major advance toward fusion energy
#248I read an article about this tonight on ScienceX.com or .org. It was quite impressive. They reached 20 teslas in their test.
Re: MIT-designed project achieves major advance toward fusion energy
#249Fusion is on my plate too. I've got a design that I really need to test, an I've finally got the funds to begin construction. My method uses much lower magnetic fields that could be provided by permanent magnets, but should allow containment times on the order of weeks for small quantities of D-D fuel. I have more information at http://www.DDproFusion.com
I love backyard science like this. No offense intended at all, but it's always heartening to see the Davids fighting the Goliaths.
Re: MIT-designed project achieves major advance toward fusion energy
#250Earlier quoted context omitted.
Point of order: if the space shuttle were grabbing satellites out of the air, something has gone terribly wrong with both launching the satellite and the shuttle.
I think the idea was that early spy satellites would use film rather than digital transmission, so it would be at the very least necessary to potentially grab one's own satellites. In any case, this exact question was asked here, and the top-rated response indicates that it's unlikely that the design requirement was ever meant to refer to grabbing an uncooperative payload: https://space.stackexchange.com/questions/41…
Parent was being overly pedantic in that satellites were likely to be grabbed out of space and not air.