6 ms·

While this is a nice project for emergency and remote uses, what we really need re: desalination in places like California (and other variable / dry climates) i

While this is a nice project for emergency and remote uses, what we really need re: desalination in places like California (and other variable / dry climates) is large-scale desalination tied to opportunity power (such as curtailed grid power). With each passing year there's going to be more and more solar on the grid, and it's going to be hard to soak up that power during the daytime peak. Desalination matches the solar supply curve perfectly: there's more water demand during the day, and there's also more water demand during the summer when there's also more sun. It's the ultimate dispatchable load.

elihu 4y ago
..also, water storage is fairly straightforward, so the water usage peak doesn't have to exactly track with the daily solar power production peak.
- hardwaresofton 4y ago
  depending on how you build the storage, you could also use the excess water for power, no? Some sort of gravity battery setup.
  - thghtihadanacct 4y ago
    got get it up there ... places like Cali dont have a lot of rain that places itself up there and runoff is running out.
    - rtkwe 4y ago
      That's the point you can pump the water higher using excess renewable energy (in the event we get past 100% peak renewable power) to be used later when there's a deficiency. It's a fairly efficient method of time-shifting renewables without having to mine huge piles of lithium.
      - Ekaros 4y ago
        Pumped hydro if geography permits is very good storage method. Efficiency is not horrible, it is simple to ramp up and down. Technology is extremely mature. It scales pretty well. And as final bonus in some cases it can contribute to grid stability.
        rtkwe 4y ago
        Yeah the biggest downside is the ecological impact of the flooding involved in creating a new hydro source. They could maybe look at retrofitting it onto an existing hydroelectric dam so it's not flooding a new area.
        ncmncm 4y ago
        A hydro power reservoir doesn't need a watershed, so can have overwhelmingly less ecological impact.
        rtkwe 4y ago
        It still needs volume to flood to hold the water though and unless we're building up artificially the cheap way to do that is to build fairly wide. All that area is habitat and covering it has an impact. In the end it's probably well worth it so long as we're not destroying rare habitats to do it but it is still destruction that has to be considered and weighed.
      - ncmncm 4y ago
        Pumping desalinated water up to Sierra Nevada reservoirs would take a hell of a lot of pipe. We use canals and rely on gravity to move water, today.
    - hardwaresofton 4y ago
      I'm going to assume you mean "up there" as in northern cali -- if we could get some clean hydrogen/electric transport trucking it shouldn't be impossible to move it around either!
    - ncmncm 4y ago
      I wonder whether the most efficient way to get water to the Sierra Nevada reservoirs would be to pump ocean water onto the desert, and let evaporation take it from there. Siphoning from the ocean into Death Valley, you wouldn't even need to pump it.
  - maxfan8 4y ago
    Yep, it’s called pumped hydro: https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricity https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricit... I think it’s very promising/exciting as a method of smoothing out the demand curves of the electric grid. Plus, it’s fairly straightforward to modify existing dams/hydro infrastructure to have this capacity. Since some dams are already used as water reservoirs for drinking/agriculture, this could be quite viable if the desalination can be done cheaply and efficiently at scale (not sure if this is even possible on the scales required for this idea to make sense, though).
    - Narkov 4y ago
      Pumped hydro has been extremely effective in Australia since the mid 1960's. There's currently a project to extend the capacity of the Snowy Hydro scheme to soak up this extra transient renewable capacity. https://www.snowyhydro.com.au/generation/the-snowy-scheme/ https://www.snowyhydro.com.au/generation/the-snowy-scheme/
      - maxfan8 4y ago
        That's cool -- I didn't know that! Imo, the more effective and cheaply we can store energy and smooth out supply/demand curves, the more attractive solar and wind becomes. Perhaps one way of encouraging a "greener" grid is to first encourage the development of cheap energy storage solutions, and then letting the market figure out the best way to utilize such storage (rather than the other way around). Might lead to more efficient/creative green energy solutions.
laurencerowe 4y ago
Do we really need expensive desalination in California? Domestic water use only accounts for 20% of demand and desalination seems unlikely to ever be cheap enough for agricultural use (the remaining 80%.)
- barathr 4y ago
  True, though there's a question of whether there will be demand to keep up those ag uses as water becomes more scarce generally (I could see it going either way). Electricity is something like half of desalination's operational cost, and we're already in a situation where the price on the grid goes negative (or is curtailed) during solar peaks and more and more solar is being added to the grid each year. So power for desalination is going to be near free in the coming years. (Whereas for other less flexible loads, electricity isn't likely to get cheaper quickly, since we have to either have storage or use gas plants.)
  - thghtihadanacct 4y ago
    The last desal plan in SoCal just got shot down ... the plant in my area was voted down not long ago as well. There needs to be a bit more suffering and research before most are going to agree to the clear negative aspects ... I love fishing and a clean Bay too. We, however, are gonna run out of water. By that time its going to be an entire California event in which the plants arent supplying just the local water districts but most of the state. At that point were just gonna eminent domain Fort Ord and build an effluent pipe half way to Kauai.
    - laurencerowe 4y ago
      I don't know if we're truly going to run out of water or not, but there are many measures it would make sense to take before building desalination plants, such as recycling water and more efficient agricultural water use.
    - Manuel_D 4y ago
      Agricultural use accounts for the overwhelming majority of water use in CA. I doubt Bay Area and LA residential faucets will go dry before water use is reformed. The rural areas are massively out-voted by the urban centers.
_8j50 4y ago
Nuclear power to the rescue (again! Lol) use excess heat from nuclear power generation and the water that gets steamed anyways for cooling and desalinate it. The brine problem can be solved by not desalinating endlessly but using desalination to create lakes and dump the brine in the desert where nuke waste is buried.
- stubish 4y ago
  Mixing corrosive saline and nuclear waste storage facilities is probably not the best idea.
- deadmutex 4y ago
  One of the big challenges: convincing people to drink water that was desalinated at a nuclear power plant.
  - coredog64 4y ago
    Where you see a challenge, I see an incredible marketing opportunity. People are buying water with a brand name of “Liquid Death”.
  - _8j50 4y ago
    Who said drinking. Use it to water all almond trees and golf grass, that takes up much more than drinking water. Or livestock too.
- wbl 4y ago
  We already have a pool of brine in the desert.
- ncmncm 4y ago
  Nuclear power is, as always, overwhelmingly more espensive than the alternative, solar. We have a great deal of desert in California, with plenty of sunshine, and evaporating only when the sun is out is fine. You wouldn't even need enclosed evaporation containers; let the wind carry the moisture to the mountains, raining into existing reservoirs.

elihu 4y ago

..also, water storage is fairly straightforward, so the water usage peak doesn't have to exactly track with the daily solar power production peak.

hardwaresofton 4y ago
depending on how you build the storage, you could also use the excess water for power, no? Some sort of gravity battery setup.
- thghtihadanacct 4y ago
  got get it up there ... places like Cali dont have a lot of rain that places itself up there and runoff is running out.
  - rtkwe 4y ago
    That's the point you can pump the water higher using excess renewable energy (in the event we get past 100% peak renewable power) to be used later when there's a deficiency. It's a fairly efficient method of time-shifting renewables without having to mine huge piles of lithium.
    - Ekaros 4y ago
      Pumped hydro if geography permits is very good storage method. Efficiency is not horrible, it is simple to ramp up and down. Technology is extremely mature. It scales pretty well. And as final bonus in some cases it can contribute to grid stability.
      - rtkwe 4y ago
        Yeah the biggest downside is the ecological impact of the flooding involved in creating a new hydro source. They could maybe look at retrofitting it onto an existing hydroelectric dam so it's not flooding a new area.
        ncmncm 4y ago
        A hydro power reservoir doesn't need a watershed, so can have overwhelmingly less ecological impact.
        rtkwe 4y ago
        It still needs volume to flood to hold the water though and unless we're building up artificially the cheap way to do that is to build fairly wide. All that area is habitat and covering it has an impact. In the end it's probably well worth it so long as we're not destroying rare habitats to do it but it is still destruction that has to be considered and weighed.
    - ncmncm 4y ago
      Pumping desalinated water up to Sierra Nevada reservoirs would take a hell of a lot of pipe. We use canals and rely on gravity to move water, today.
  - hardwaresofton 4y ago
    I'm going to assume you mean "up there" as in northern cali -- if we could get some clean hydrogen/electric transport trucking it shouldn't be impossible to move it around either!
  - ncmncm 4y ago
    I wonder whether the most efficient way to get water to the Sierra Nevada reservoirs would be to pump ocean water onto the desert, and let evaporation take it from there. Siphoning from the ocean into Death Valley, you wouldn't even need to pump it.
- maxfan8 4y ago
  Yep, it’s called pumped hydro: https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricity https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricit... I think it’s very promising/exciting as a method of smoothing out the demand curves of the electric grid. Plus, it’s fairly straightforward to modify existing dams/hydro infrastructure to have this capacity. Since some dams are already used as water reservoirs for drinking/agriculture, this could be quite viable if the desalination can be done cheaply and efficiently at scale (not sure if this is even possible on the scales required for this idea to make sense, though).
  - Narkov 4y ago
    Pumped hydro has been extremely effective in Australia since the mid 1960's. There's currently a project to extend the capacity of the Snowy Hydro scheme to soak up this extra transient renewable capacity. https://www.snowyhydro.com.au/generation/the-snowy-scheme/ https://www.snowyhydro.com.au/generation/the-snowy-scheme/
    - maxfan8 4y ago
      That's cool -- I didn't know that! Imo, the more effective and cheaply we can store energy and smooth out supply/demand curves, the more attractive solar and wind becomes. Perhaps one way of encouraging a "greener" grid is to first encourage the development of cheap energy storage solutions, and then letting the market figure out the best way to utilize such storage (rather than the other way around). Might lead to more efficient/creative green energy solutions.

laurencerowe 4y ago

Do we really need expensive desalination in California? Domestic water use only accounts for 20% of demand and desalination seems unlikely to ever be cheap enough for agricultural use (the remaining 80%.)

barathr 4y ago
True, though there's a question of whether there will be demand to keep up those ag uses as water becomes more scarce generally (I could see it going either way). Electricity is something like half of desalination's operational cost, and we're already in a situation where the price on the grid goes negative (or is curtailed) during solar peaks and more and more solar is being added to the grid each year. So power for desalination is going to be near free in the coming years. (Whereas for other less flexible loads, electricity isn't likely to get cheaper quickly, since we have to either have storage or use gas plants.)
- thghtihadanacct 4y ago
  The last desal plan in SoCal just got shot down ... the plant in my area was voted down not long ago as well. There needs to be a bit more suffering and research before most are going to agree to the clear negative aspects ... I love fishing and a clean Bay too. We, however, are gonna run out of water. By that time its going to be an entire California event in which the plants arent supplying just the local water districts but most of the state. At that point were just gonna eminent domain Fort Ord and build an effluent pipe half way to Kauai.
  - laurencerowe 4y ago
    I don't know if we're truly going to run out of water or not, but there are many measures it would make sense to take before building desalination plants, such as recycling water and more efficient agricultural water use.
  - Manuel_D 4y ago
    Agricultural use accounts for the overwhelming majority of water use in CA. I doubt Bay Area and LA residential faucets will go dry before water use is reformed. The rural areas are massively out-voted by the urban centers.

_8j50 4y ago

Nuclear power to the rescue (again! Lol) use excess heat from nuclear power generation and the water that gets steamed anyways for cooling and desalinate it. The brine problem can be solved by not desalinating endlessly but using desalination to create lakes and dump the brine in the desert where nuke waste is buried.

stubish 4y ago
Mixing corrosive saline and nuclear waste storage facilities is probably not the best idea.
deadmutex 4y ago
One of the big challenges: convincing people to drink water that was desalinated at a nuclear power plant.
- coredog64 4y ago
  Where you see a challenge, I see an incredible marketing opportunity. People are buying water with a brand name of “Liquid Death”.
- _8j50 4y ago
  Who said drinking. Use it to water all almond trees and golf grass, that takes up much more than drinking water. Or livestock too.
wbl 4y ago
We already have a pool of brine in the desert.
ncmncm 4y ago
Nuclear power is, as always, overwhelmingly more espensive than the alternative, solar. We have a great deal of desert in California, with plenty of sunshine, and evaporating only when the sun is out is fine. You wouldn't even need enclosed evaporation containers; let the wind carry the moisture to the mountains, raining into existing reservoirs.