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131 points mg | 2 comments | | HN request time: 0.411s | source
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zizee ◴[] No.26598033[source]
I think the future will be robust national/international grids, with a mixture of storage options (batteries/pumped hydro) to smooth out the intermittent nature of wind and solar.

Cynics always talk about the amount of energy storage required for solar as if you need to store 24 hours of energy for solar/wind to be viable.

I'd like to see numbers on having 1 hour of storage for peak demand, a robust national grid, and appropriately provisioned and placed solar and wind, taking the duck curve into consideration.

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elihu ◴[] No.26599340[source]
I wonder what the limits are on transmitting power around the world? Like, if we wanted to connect Northern Africa to the North American power grid, how feasible would it be, and what would the losses and power capacity be?

It seems that with all the interest in using ReBCO tape in tokomaks due to its ability to transmit more power at higher temperatures than the materials that preceded it (used, for example in ITER) that it could be used to transmit power over long distances. Has anyone actually done it yet, or is it just too expensive? (Apparently the current capacity of superconducting cable is finite; if you run too much current through it, it'll transition to becoming non-superconducting. So maybe the amount of ReBCO tape needed per unit of power or the amount of active cooling needed makes it impractical.)

Eventually, to be able to usefully transmit power from daytime sun to nighttime will require crossing oceans. Which I imagine would be tough to do with a cable has to be actively cooled and work for many years without maintenance. Maybe for my hypothetical North America to North Africa route, you'd run a superconducting cable down through Central and South America over to Brazil, then have a normal high-voltage DC line across the Atlantic, with another superconducting cable that crosses the Sahara.

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fpgaminer ◴[] No.26600131[source]
I dunno, back of the envelope says you'd only lose 33% with today's HVDC lines from North Africa to North America. The ocean will sink the lost energy for us. And we can make up the difference with more solar/wind, which is cheap.

Superconducting would be nice to have, but doesn't seem necessary.

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elihu ◴[] No.26600743[source]
Huh, that's actually not bad. That makes the idea of connecting Asia/Africa/Europe with the Americas for 24-hour solar power seem doable. I assume it would be tremendously expensive to build, but also have substantial benefits long into the future.
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1. mtalhaashraf ◴[] No.26601156[source]
The level of dependency on others and the associated risks would likely discourage this
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2. elihu ◴[] No.26606264[source]
That's true to a degree; if someone were able to cripple half the world's economies just by disabling a cable then yes, that's a serious issue. On the other hand, if all the involved countries maintained backup power (i.e. gas or coal generation) that could be turned on in an emergency but otherwise unused, then the risks could be mitigated.

Backup generators would of course be expensive to build and maintain, but if they just sit idle 99% of the time maybe the cost would be acceptable. I assume a fossil fuel power plant that just sits idle could last a very long time.