Nuclear is back on the table for a green future

Post by p1necone » Thu, Jun 16, 2022, 1:09 AM UTC

credit_guy wrote: post #558

Solar and wind have a storage problem. Day-to-night storage is a solved problem, but summer-to-winter is very far from being solved. Batteries, pumped hydro, flywheels, compressed air are simply off by factors of 100x or more. There are just 2 plausible solutions: chemical storage, or massive overcapacity. Chemical storage means hydrogen, or ammonia, or iron powder, or some other substance that can undergo reversible…

Post by WalterBright » Thu, Jun 16, 2022, 1:29 AM UTC

philwelch wrote: post #160

adrianN wrote: post #140

Earlier quoted context omitted.

I don't think that's a common use of "unsolved at scale". We know how to do it, it just doesn't make economic sense right now. I mean, suppose you have hundreds of GW of storage of some form installed. You could just claim it's still not "solved at scale" because the global energy consumption is even higher.

The global supply chains for lithium batteries are already struggling to keep up just with current demand. Where are we going to get enough cobalt? Hopefully not DR Congo.

Post by WalterBright » Thu, Jun 16, 2022, 1:31 AM UTC

californical wrote: post #505

sanderjd wrote: post #469

Earlier quoted context omitted.

Why? What will the rest be?

I know there are options like pumped water, compressed air, spinning disc. No idea how feasible they are at scale, but I can imagine a world where physical storage like that could be lower maintenance & cost in the long-term compared to chemical batteries. Even if less efficient, you can get enormous potential storage from pumped water with relatively simple machines compared to massive battery farms.

Post by pfdietz » Thu, Jun 16, 2022, 1:36 AM UTC

Manuel_D wrote: post #559

pfdietz wrote: post #552

Earlier quoted context omitted.

So what if it's used for chemical processes? To make it efficient, there is careful transfer of heat from the input stream to the outgoing streams, with compression/expansion to convert the heat energy back to work. Making this efficient involves just the kinds of components that are needed in a cryogenic energy store.

You correctly point out that air separation is made efficient by transferring the heat from the output stream to the input stream. After cooling air enough to isolate whatever chemical is needed (like nitrogen) the cold output stream is run back through the warm input stream to help cool the input stream. This also has the effect of warming the output stream back to ambient temperature. This is fine if you're separat…

Post by pfdietz » Thu, Jun 16, 2022, 1:40 AM UTC

philwelch wrote: post #557

pfdietz wrote: post #550

Earlier quoted context omitted.

We've had demo reactors with various issues, none of which demonstrated they could compete even with burner reactors. I remind you the double standard involved criticizing renewables "at scale", so a few problematic breeder reactors won't dispel the hypocrisy.

For what it's worth, I'm not suggesting using breeder reactors as a primary source of electrical power, but as an option for reprocessing transuranic waste and spent fuel. So totally different levels of scale. Also, the main reason we haven't invested in breeder reactors is that it turns out uranium isn't actually scarce enough to justify it.