10 ms·

Pumped storage analysis: https://dothemath.ucsd.edu/2011/11/pump-up-the-storage/ https://dothemath.ucsd.edu/2011/11/pump-up-the-storage/ spoiler: not remotely

Pumped storage analysis: https://dothemath.ucsd.edu/2011/11/pump-up-the-storage/ https://dothemath.ucsd.edu/2011/11/pump-up-the-storage/ spoiler: not remotely possible to scale large enough for total world needs. "If we drained one meter from every upper lake, we would get 54 billion kWh of energy: about a sixth of the target capacity. If performed over seven days, the flow would be 375,000 cubic meters per second, or 125 times the normal flow over the falls." "We would need 10,000 Raccoon Mountains to meet my baseline energy capacity"

JoeAltmaier 8y ago
Isn't that about covering for outages? Those may never be solved. This article was about storing off-peak green energy for peak usage. We're talking only about an hour or two of usage? Not 7 days. Those number may pencil out very well.
dragontamer 8y ago
> spoiler: not remotely possible to scale large enough for total world needs. Yeah, not with those assumptions. Storing enough energy for 7-days worth of zero-sun and zero-wind is going to be basically impossible across all known energy storage technologies. We'll likely have to run peaker plants during such an extended outage. But we're not even trying to solve the 7-days worth of energy problem. We're starting with: lets save 3-hours worth of energy, so that the 6pm sun can be used for air-conditioning until 9pm or so. Which we're not at yet (see the "Duck Curve" or "Nessie curve"). Besides, being able to store energy for 1 or 2 hours is still SUPER useful. Wind is strongest at night, while Solar is strongest during noon. Having energy at dawn (sun isn't strong yet) or twilight (sun is setting, but the wind hasn't picked up yet) is going to be a huge portion of our future energy strategy. ----------- A huge part of the problem can be solved behaviorally and economically. We can change the price of electricity based on how easy it is to produce. 12:00 noon (highest sun power) can be cheaper, and 3am power (max wind energy) can also be cheaper. Night-time energy can be used to power electric cars. 12:00 noon power can be used for factory work and other high-energy tasks (Air Conditioning, Washing Machines). We all can change our behavior to reduce our energy demand between 5pm and 8pm, to reduce the Nessie curve / duck curve. And we can use economics to set the price higher to encourage others to follow our lead. --------- Throw down a bit of nuclear, and keep a few natural gas peaker plants active for emergencies, and I think we've got a strong future for energy. At the end of the day: Pumped Hydro is the ONLY GW-hr solution to this energy storage question. CAES is hundreds-of-MW-hrs, while Lithium Ion is also only hundreds-of MW-hrs. That's just how the cookie crumbles: we don't have any other technology to store GW-hrs of energy.
- WhompingWindows 8y ago
  When is there zero sun? I didn't realize that was a possibility on our spinning planet
  - galuano1 8y ago
    Cloudy days.
    - Retric 8y ago
      Solar still provides power on Cloudy days, just less. Storage is still a poor solution to this problem it’s much cheaper to have excess renuables.
    - pjc50 8y ago
      A far more serious consideration for solar is the changing seasons, especially at non-tropical latitudes. I graphed the output of my solar panels (56 north, Scotland) and it's really apparent: https://flatline.org.uk/daystats.html https://flatline.org.uk/daystats.html
      - PhantomGremlin 8y ago
        So those panels are basically useless for 3 or 4 months of the year, i.e. November, December, January, February. Would there be much improvement if you could tweak the orientation to match the seasons? E.g. tilt them down toward the horizon during the winter? It's certainly a huge complication to have motorized panels that move all the time to track the sun. But maybe it wouldn't be that much of a hassle to go out there and manually reorient them (just in 1 axis) a few times a year?
        pjc50 8y ago
        They're fixed to the roof, so making them movable would be a risk to their safety and wind resistance while being fairly difficult to access (and ladders are dangerous). For a fairly small benefit. It's not just the angle but the sunrise and sunset are a lot closer together.
mirekrusin 8y ago
Can you "decorate/boost" those dams with inflatable ballons on the lake's floor?
Pxtl 8y ago
Compressed air is cheaper and has less geographic needs but it's even less efficient.

JoeAltmaier 8y ago

Isn't that about covering for outages? Those may never be solved. This article was about storing off-peak green energy for peak usage. We're talking only about an hour or two of usage? Not 7 days. Those number may pencil out very well.

dragontamer 8y ago

> spoiler: not remotely possible to scale large enough for total world needs. Yeah, not with those assumptions. Storing enough energy for 7-days worth of zero-sun and zero-wind is going to be basically impossible across all known energy storage technologies. We'll likely have to run peaker plants during such an extended outage. But we're not even trying to solve the 7-days worth of energy problem. We're starting with: lets save 3-hours worth of energy, so that the 6pm sun can be used for air-conditioning until 9pm or so. Which we're not at yet (see the "Duck Curve" or "Nessie curve"). Besides, being able to store energy for 1 or 2 hours is still SUPER useful. Wind is strongest at night, while Solar is strongest during noon. Having energy at dawn (sun isn't strong yet) or twilight (sun is setting, but the wind hasn't picked up yet) is going to be a huge portion of our future energy strategy. ----------- A huge part of the problem can be solved behaviorally and economically. We can change the price of electricity based on how easy it is to produce. 12:00 noon (highest sun power) can be cheaper, and 3am power (max wind energy) can also be cheaper. Night-time energy can be used to power electric cars. 12:00 noon power can be used for factory work and other high-energy tasks (Air Conditioning, Washing Machines). We all can change our behavior to reduce our energy demand between 5pm and 8pm, to reduce the Nessie curve / duck curve. And we can use economics to set the price higher to encourage others to follow our lead. --------- Throw down a bit of nuclear, and keep a few natural gas peaker plants active for emergencies, and I think we've got a strong future for energy. At the end of the day: Pumped Hydro is the ONLY GW-hr solution to this energy storage question. CAES is hundreds-of-MW-hrs, while Lithium Ion is also only hundreds-of MW-hrs. That's just how the cookie crumbles: we don't have any other technology to store GW-hrs of energy.

WhompingWindows 8y ago
When is there zero sun? I didn't realize that was a possibility on our spinning planet
- galuano1 8y ago
  Cloudy days.
  - Retric 8y ago
    Solar still provides power on Cloudy days, just less. Storage is still a poor solution to this problem it’s much cheaper to have excess renuables.
  - pjc50 8y ago
    A far more serious consideration for solar is the changing seasons, especially at non-tropical latitudes. I graphed the output of my solar panels (56 north, Scotland) and it's really apparent: https://flatline.org.uk/daystats.html https://flatline.org.uk/daystats.html
    - PhantomGremlin 8y ago
      So those panels are basically useless for 3 or 4 months of the year, i.e. November, December, January, February. Would there be much improvement if you could tweak the orientation to match the seasons? E.g. tilt them down toward the horizon during the winter? It's certainly a huge complication to have motorized panels that move all the time to track the sun. But maybe it wouldn't be that much of a hassle to go out there and manually reorient them (just in 1 axis) a few times a year?
      - pjc50 8y ago
        They're fixed to the roof, so making them movable would be a risk to their safety and wind resistance while being fairly difficult to access (and ladders are dangerous). For a fairly small benefit. It's not just the angle but the sunrise and sunset are a lot closer together.

mirekrusin 8y ago

Can you "decorate/boost" those dams with inflatable ballons on the lake's floor?

Pxtl 8y ago

Compressed air is cheaper and has less geographic needs but it's even less efficient.