4 ms·

Rather than batteries, i think pumping water up a hill will be a lot cheaper. use the water to drive a generator. massive daily over production to fill the nigh

by jfoutz 11y ago

Rather than batteries, i think pumping water up a hill will be a lot cheaper. use the water to drive a generator. massive daily over production to fill the nightly (or much longer) reserve.

taf2 11y ago
I like this idea a lot the only downside is it expands the land area and possibly increases complexity - but I think for major power planets it's a great option just not for the home installations.
gumby 11y ago
That is the state of the art for energy storage today and basically all the sites are taken. Sure, if energy costs go up a LOT a few more will become viable, but if you look around, for example, Californa, it's hard to find another viable site.
- jfoutz 11y ago
  I'd bet you know far more about it than i do. Assuming solar gets super super cheap, well, then we can do a lot. like suffer the losses of long distance transmission lines. Arizona supplying California might be feasible if the solar panels are cheap enough. Parent poster seems to be implying a few bucks a panel, rather than thousands or even hundreds of dollars.
  - xyzzyz 11y ago
    >Arizona supplying California might be feasible if the solar panels are cheap enough. For 1000 kV AC transmission line from Arizona to California, transmission losses should certainly be smaller than 5%, even less for DC. Arizona is pretty close to California when it comes to electricity transmission.
- dredmorbius 11y ago
  Seawater lower basin adds considerably to site count. There are other concerns: elevated highly variable salt water ponds and wetlands, and general nastiness of saltwater engineering: corrosion and marine life growth especially. But generally, pumped hydro is really hard to beat.
- rmc 11y ago
  Belgium is building an artificial island in the sea for this http://www.technologyreview.com/view/510806/a-manmade-island-to-store-wind-energy/ http://www.technologyreview.com/view/510806/a-manmade-island...
slyall 11y ago
Pumped storage is hard to scale down and has a fairly fixed loss. There are a bunch of other storage technologies that are at the "almost there" stage though. I personally like the Pumped Heat storage from Isentropic as a possible mainstream contender: http://www.isentropic.co.uk/ http://www.isentropic.co.uk/
- kitd 11y ago
  That looks really interesting, though I wonder about the energy losses in the pumping mechanism. Are pistons particularly efficient? As an added bonus, they're based just down the road from me!
  - pjc50 11y ago
    Piston efficiency is basically limited by leakage round the seals and friction on the bearings. Can be in the very high 90%s. The system efficiency is limited by Carnot cycle like everything else, I think; they are claiming 75% AC-AC round trip, which is impressive if true.

by jfoutz 11y ago

Rather than batteries, i think pumping water up a hill will be a lot cheaper. use the water to drive a generator. massive daily over production to fill the nightly (or much longer) reserve.

taf2 11y ago

I like this idea a lot the only downside is it expands the land area and possibly increases complexity - but I think for major power planets it's a great option just not for the home installations.

gumby 11y ago

That is the state of the art for energy storage today and basically all the sites are taken. Sure, if energy costs go up a LOT a few more will become viable, but if you look around, for example, Californa, it's hard to find another viable site.

jfoutz 11y ago
I'd bet you know far more about it than i do. Assuming solar gets super super cheap, well, then we can do a lot. like suffer the losses of long distance transmission lines. Arizona supplying California might be feasible if the solar panels are cheap enough. Parent poster seems to be implying a few bucks a panel, rather than thousands or even hundreds of dollars.
- xyzzyz 11y ago
  >Arizona supplying California might be feasible if the solar panels are cheap enough. For 1000 kV AC transmission line from Arizona to California, transmission losses should certainly be smaller than 5%, even less for DC. Arizona is pretty close to California when it comes to electricity transmission.
dredmorbius 11y ago
Seawater lower basin adds considerably to site count. There are other concerns: elevated highly variable salt water ponds and wetlands, and general nastiness of saltwater engineering: corrosion and marine life growth especially. But generally, pumped hydro is really hard to beat.
rmc 11y ago
Belgium is building an artificial island in the sea for this http://www.technologyreview.com/view/510806/a-manmade-island-to-store-wind-energy/ http://www.technologyreview.com/view/510806/a-manmade-island...

slyall 11y ago

Pumped storage is hard to scale down and has a fairly fixed loss. There are a bunch of other storage technologies that are at the "almost there" stage though. I personally like the Pumped Heat storage from Isentropic as a possible mainstream contender: http://www.isentropic.co.uk/ http://www.isentropic.co.uk/

kitd 11y ago
That looks really interesting, though I wonder about the energy losses in the pumping mechanism. Are pistons particularly efficient? As an added bonus, they're based just down the road from me!
- pjc50 11y ago
  Piston efficiency is basically limited by leakage round the seals and friction on the bearings. Can be in the very high 90%s. The system efficiency is limited by Carnot cycle like everything else, I think; they are claiming 75% AC-AC round trip, which is impressive if true.