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Re:US Army deploys its first floating solar array by Mwow on Friday June 17, 2022 @11:51AM (#31780006)
Another idea I saw on yt a few months back:

Charge some solid state battery (it's not battery it was something better) and then transport it.

Similar on how we ship oil across the planet.

Re:US Army deploys its first floating solar array by foxyv on Friday June 17, 2022 @12:16PM (#31780410)
Robert A. Heinlein wrote a book called Friday that had something like this. They would use huge solar arrays to charge proprietary solid state batteries called Shipstones which were used everywhere. There wasn't even a power grid anymore because people would just buy a Shipstone and put it into their house and replace it every so often like coal in a coal bin.
Re:US Army deploys its first floating solar array by johncearls on Friday June 17, 2022 @05:44PM (#31784773)
I love Friday and just reread it last weekend. Often I think that Elon Musk believes he is a character in a Heinlein novel. Tesla is Shipstone, the cars are just a mechanism to build better batteries. SpaceX, that's just DD Harriman from the man who sold the moon/sail beyond the sunset. The Boring company is how you build Luna City ala The moon is a harsh mistress. Or maybe a space catapult. Or maybe, I'm just hoping for Heinleinian hero.
Re:US Army deploys its first floating solar array by ncmncm on Friday June 17, 2022 @06:25PM (#31785210)
Anti-hero, more like. Or, in the instant case, over-funded buffoon.
Re:US Army deploys its first floating solar array by chipsa on Friday June 17, 2022 @01:41PM (#31781644)
A big problem with that is energy density. Hydrocarbons are on the order of 50MJ/kg. Li-ion batteries are on the order of .5MJ/kg.
Re:US Army deploys its first floating solar array by ncmncm on Friday June 17, 2022 @06:27PM (#31785231)
Lithium tech at this exact instant is not the end state of battery development.

So, not a big problem, a speed bump. Check back next year.

Re:US Army deploys its first floating solar array by ch4s3 on Friday June 17, 2022 @12:19PM (#31780464)
I think the problem here is the weight of the batteries and the need for power to move them. Maybe hydrogen by electrolysis would be more favorable, but then you need to pipe in water.
Re:US Army deploys its first floating solar array by chipsa on Friday June 17, 2022 @01:36PM (#31781567)
You don't necessarily need to pipe the water to the electricity, you can move the electricity to where the water is (and if the electrolysis works with seawater, you don't need freshwater either). And then you can turn it into something like Methane or Ammonia for longer term storage. And the long term storage is important to level the power production over the course of months.
Re:US Army deploys its first floating solar array by ch4s3 on Friday June 17, 2022 @01:53PM (#31781826)
I think the issue at hand is that long distance transmission of electricity has transmission loss, and is expensive from an infrastructure standpoint. The broader point is that remote solar generation presents some challenges.
Re:US Army deploys its first floating solar array by ncmncm on Friday June 17, 2022 @06:28PM (#31785251)
Transmission loss matters very little anymore. You just add more panels at the source. Marginal cost of the loss is zero. It is very, very cheap to deliver power by transmission line.
Re:US Army deploys its first floating solar array by chipsa on Friday June 17, 2022 @03:20PM (#31783020)
Yes, I made exactly that point above. But the point I'm making is that long distance transmission of water is also expensive from an infrastructure standpoint, possibly even more expensive than power (and also sometimes has transmission losses, depending on how they're moving it)
Re:US Army deploys its first floating solar array by ch4s3 on Friday June 17, 2022 @03:25PM (#31783075)
> But the point I'm making is that long distance transmission of water is also expensive

Oh yeah, in case I wasn't clear that's exactly what I meant also.

The dream of covering a chunk of the Sahara in PV to power Europe and Africa seems like tilting at windmills.

Re:US Army deploys its first floating solar array by ncmncm on Friday June 17, 2022 @07:19PM (#31785727)
But not for the reason you think.

The right place to put PV for Europe is in Europe. You will want solar farms in the tropics producing ammonia to ship around to wherever the wind flags for a few weeks, and to Finland in winter.

Re:US Army deploys its first floating solar array by ncmncm on Friday June 17, 2022 @07:18PM (#31785720)
Transmitting power is not, in fact, expensive.

Building an HVDC transmission line has capital cost, but marginal operating cost is near zero.