[cupofpython]

>For serious bulk long-term storage it would be hard to beat ammonia

Is this related to flow batteries? Right now I think pumped storage is winning (where applicable), but I've heard flow batteries are more powerful

>What needs work is economical ways to get carbon out of the air

Isn't it kind of wild that too much carbon is a problem? A core building block for life on earth. I agree though, next decade is important for carbon research as well. Olivine is interesting

https://energsustainsoc.biomedcentral.com/articles/10.1186/2...

>Do we really need AI for anything?

The current research is a valid next step in automation which has always shown to have good ROI imo. I dont think it's very "I" but the algorithms have proven very good at outperforming prior heuristics. this enables automation in areas that have unknowns that cannot be explicitly defined as required by prior tooling. the use-cases it settles into are going to be undeniably better for it, but there is a lot of noise right now with people trying to use it for everything

[ncmncm]

Pumped storage is certainly the easiest thing to deploy right now, anywhere you have hills. There are projects to make pumped hydro work where there are no hills, but there are deep underground cavities, or deep ocean near enough by you can put a tank under. In those, you pump water up from a space or tank below, and let water back into it to discharge. For the latter, you don't even need a long pipe, just a pump/turbine at the bottom of the tank, so it doesn't even need to be very nearby, just near enough to run a transmission line to. (That applies to any pumped hydro, BTW.)

Ammonia means, simply, synthesizing anhydrous ammonia from environmental nitrogen and hydrogen (that electrolysed from water). To get the power back out, you burn it in your gas turbine, or (in future) use fuel cells. The attractions are that excess ammonia may be sold on the open market, so your synthesis equipment sits idle only when you are actually drawing down on your tank; and it doesn't cost anything more than the tankage to bank it indefinitely. If you need more ammonia than you have banked, you just buy it, maybe shipped in from a solar farm in the tropics.

Remarkably, if you have just enough of some more round-trip efficient storage to get you through the night, the round-trip efficiency of the ammonia, hydrogen, liquified nitrogen, or what-have-you doesn't matter very much. Solar panels are so cheap, you can afford to be wasteful.

Carbon is the 4th most abundant substance in the universe. What is wild is that life is good enough at stealing it away from oxygen to have almost scrubbed it out of our atmosphere. (Compare to Venus.)

It will be important to get the carbon back out of the air, and then not turn around and, as everybody seems so eager to do, burn and exhaust it again. A business model where we end up with the carbon sequestered has been hard to come up with.

There was a suggestion to make it into fiber and put that in cement, thereby strengthening concrete so you don't need as much; but the best source for that carbon is cement manufacture itself, which exhausts CO2 at much higher concentration than in the atmosphere. So, it only helps much if you need a lot more carbon for that than you would have exhausted.

[cupofpython]

>Remarkably, if you have just enough of some more round-trip efficient storage to get you through the night, the round-trip efficiency of the ammonia, hydrogen, liquified nitrogen, or what-have-you doesn't matter very much. Solar panels are so cheap, you can afford to be wasteful.

i wonder if round-trip efficiency really is all that negligible when solar panel development and shipping is no longer subsidized by fossil fuels and must also use the energy-storage tech of choice as the predominant source of energy for anything not directly hooked up to the grid. a 20% RTE efficiency has a 5x impact on required energy to do anything. Are there enough good locations for solar to cover the needs of all long-term storage needs 5x over? Do we have enough raw materials for that many panels? Seems plausible tbh but idk

In any case, isn't ammonia incredibly toxic? whats the work-around there? we assume perfect handling of it by all parties at every level of a globally large scale operation? A gasoline leak is bad enough, but an ammonia pipeline bursting? that seems like a hard sell

[ncmncm]

Cost for solar panels is still in free fall. Nothing is being subsidized at anything like the amount we pay for oil extraction: every last barrel pumped is paid out for, cash on the barrelhead, hundreds of $billions every year. You pay for a panel exactly one time, and then it delivers for years.

The point about round-trip efficiency being negligible is that you only rarely need to draw down on those easy-to-ship, easy-to-store media. All you need is, say, 2x more panels to use to top them up again. Most of the time, those extra panels are driving synthesis to sell, generating revenue.

Shipping is always cheap. In the future, we can expect the ships to burn ammonia synthesized in the tropics.

Storage costs are falling even faster than for solar panels.

Solar can be co-sited with roofs, where it extends the life of the roof; with parking lots, where it extends the life of the cars; with reservoirs and canals, where it cuts evaporation and biofouling, and also operates cooler, thus 3% more efficiently; and with pasture and farmland, where it increases yield by reducing heat stress, and cuts water demand. So, yes, there is way more room for solar panels than you will ever want.

Solar panels are usually made of silicon, which makes up 28% of the Earth's crust. The mass of solar panels needed per kW is falling even faster than their cost.

Ammonia is toxic. But we already handle literally millions of tons of it every year without incident. It is lighter than air, so if it leaks, it can't blanket a nearby town like, say (just picking at random) methyl isocyanate.