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points by crote 3 days ago | 0 comments
It won't.

The main problem with solar and wind is that they can't be dispatched on demand. The power is incredibly cheap, but you are completely at the mercy of the weather.

What is needed is a source of power which can make up for the freak moments where 1) there isn't any sun, and 2) there isn't any wind, and 3) it lasts long enough that batteries can't cover it, and 4) it has to be widespread enough that you can't make up for it with power from half a continent away.

This power source will only need to be used for a few hundred hours per year but it'll need to carry a significant load, so while its per-MWh running costs are basically irrelevant its one-time per-MW construction costs should be fairly low.

This does not at all describe nuclear power, which has incredibly high construction costs, near-zero running costs, and is expected to run 24/7/365 at 100%.

[–] __MatrixMan__ 3 days ago
I'm optimistic about synthetic hydrocarbons for that use case. The infra is already in place for storage, delivery, consumption. You gotta waste some energy to get it, but if sun and wind is cheap most of the time, who cares?
[–] zahlman 3 days ago
> synthetic hydrocarbons

I don't follow. Why would they be any less polluting than natural ones?

[–] tialaramex 2 days ago
In and of themselves the hydrocarbons are molecules with only Carbon and Hydrogen atoms. So, they're polluting only in the sense that we should not release more Carbon Dioxide into our atmosphere because due to the Greenhouse Effect that causes Climate Disaster.

In terms of regular old "Oh, no, it's toxic" pollution this part was fine, and the problem in the "natural" hydrocarbons is that they were not actually pure hydrogen and carbon - especially coal. So you just wouldn't do that in the synthetics. It's likely easier to make "pure" synthetics.

In terms of climate, the synthetics would be cycling carbon that already exists. So they'd be neutral. Neutral isn't a solution, but it's at least not making the problem even worse which we are aggressively continuing to do as a species.

[–] __MatrixMan__ 2 days ago
Because we'd be making them out of CO2 pulled from the atmosphere in the first place. We wouldn't be putting any new carbon into the atmosphere, just recycling carbon that's already there. And the larger our fuel stockpiles get, the more carbon we've sequestered. I think it has better economic incentives than pumping CO2 down into the earth or something like that.
[–] zahlman 2 days ago
Cycling carbon between CO2 and synthetic hydrocarbons, and presumably using clean energy for the recovery step, seems like basically just a complex solar+battery scheme (and I can't really see it being more efficient, although it produces denser storage). Sequestering the CO2 in carbonate rock makes more sense to me (and that has actual chemical uses too).
[–] defrost 2 days ago
Alternatively, sequestering in ultramafic rock to transform to carbonate rock and make a bit of orange hydrogen on the side to power the scheme.

* https://research.csiro.au/carbonlock/geological-properties-o...

* https://www.sciencedirect.com/science/article/pii/S036031992...

[–] khalic 3 days ago
Because they would be generated with CO2 by industrial processes or carbon capture. I don't see the process becoming economically viable, and hydrocarbon combustion create other toxic byproducts, compared to hydrogen. It will still make sense for usages that require a high J/kg fuel ratio.
[–] __MatrixMan__ 2 days ago
Do you see any other carbon capture scheme becoming economically viable? I mean, if we must put atmospheric carbon in tanks anyhow, why not package it as fuel so that we can burn it later if we need to?

Spring and fall are peak solar collection times, summer and winter are peak energy use times. So collect the carbon in fall, burn it in winter, re-collect it in spring, burn it in summer...