14 ms·

With solar energy prices plummeting, it may make sense during peak production hours to use it to do desalination and/or extract water from the air, depending on

• cyanydeez 3y ago
  they're testing some new tech that directly uses the sun to desalinate. Really, what's required for the electric grid is ways to store the energy, and not use it. For places like Arizona, they may need a whole different type of infrastructure of grey water use. Just piping in water ain't gonna be sustainable.
  • bryanlarsen 3y ago
    Water is a lot easier to store than electricity. Desalinate while the sun is shining to fill a reservoir that you can pull from 24/7.
    • toomuchtodo 3y ago
      True, but it isn't energy, and desal requires firm generation, so you're not using renewables that would've been curtailed but instead competing with load that needs consistent power. Still hopeful considering the cost decline curve of utility scale storage, but it isn't a silver bullet based on solar being free at noon.
      • nosrepa 3y ago
        But water in a reservoir is one of the oldest ways of storing energy.
      • scythe 3y ago
        >desal requires firm generation Most existing plants are designed for this, but it is by no means necessary. https://www.sciencedirect.com/science/article/pii/S0011916420305403 https://www.sciencedirect.com/science/article/pii/S001191642... >This work analyses the long-term performance of a full-scale brackish water reverse osmosis (BWRO) desalination plant that has been working under intermittent operating conditions for 14 years (~9 h d−1).
        • toomuchtodo 3y ago
          TIL. Appreciate the correction.
      • matthewdgreen 3y ago
        You combine the desalination with pumped hydro storage. Or you just deploy it with intermittent power, as the other poster pointed out. https://spectrum.ieee.org/amp/pumped-storage-hydropower-2666647371 https://spectrum.ieee.org/amp/pumped-storage-hydropower-2666...
    • mjhay 3y ago
      Why do you need to desalinate it to use it for energy storage? Seems like an unnecessary step that would not increase the gravitational potential energy at all.
      • 57FkMytWjyFu 3y ago
        You really don't want to mix salty water with machines unless you have to.
        • mjhay 3y ago
          It's done routinely in ships and such. It's certainly much easier than the energy and machinery it would take for desalination.
          • 57FkMytWjyFu 3y ago
            No, it isn't easier, it's done on ships for lack of choice.
    • mr_toad 3y ago
      > Water is a lot easier to store than electricity. Desalinate while the sun is shining to fill a reservoir that you can pull from 24/7. Cheap to store, expensive to transport. Desalinisation only makes sense if you are near the coast and short of water. Further inland it becomes uneconomical. The Earth is not short on fresh water, the problem is getting fresh water where it is needed.
    • nwah1 3y ago
      Pumped storage hydro is a way to store energy, but also can dispense water.
  • tedk-42 3y ago
    > they're testing some new tech that directly uses the sun to desalinate. We should be implementing technologies we have now today rather than banking on something that might or might not pan out. I don't hate the idea of piping water throughout areas or creating artificial enclosed canals of sorts. But then I'm on the side of thinking that we should advance and terraform the planet rather than try to be more one with nature and cut back.
    • arcticbull 3y ago
      So a nuclear power plant adjacent to the ocean and a desal plant?
      • zer00eyz 3y ago
        https://en.wikipedia.org/wiki/Fukushima_nuclear_accident https://en.wikipedia.org/wiki/Fukushima_nuclear_accident We can have safe nuclear power, right after we invent safe people. Till you solve the human problem nukes are bad mmmkay.
        • arcticbull 3y ago
          Nobody died in Fukushima, except in a bungled evacuation of the surrounding area. Maybe one person in the fullness of time. Nuclear power is literally the safest power source in deaths per TWh - right between wind and solar. [1] We have safe nuclear power, so I'm pleased to inform you that your concern was mitigated, about 50 years ago. [edit] Also, I would point out the worst nuclear accident in history killed 4000 people according to USCEAR. The next-worst killed 1. The worst hydro accident in history (Bangqiao Dam) killed 240,000, damaged 5 million homes, displaced 10.5 million people and wiped several cities off the face of the earth - yet for some reason it doesn't share the same perception of intense danger. Interesting. [2] [1] https://ourworldindata.org/safest-sources-of-energy https://ourworldindata.org/safest-sources-of-energy [2] https://en.wikipedia.org/wiki/1975_Banqiao_Dam_failure https://en.wikipedia.org/wiki/1975_Banqiao_Dam_failure
          • 3y ago
  • jsbisviewtiful 3y ago
    > they're testing some new tech that directly uses the sun to desalinate. I'm intrigued. Link?
• justinzollars 3y ago
  > solar energy prices plummeting Shopping for solar in California, prices aren't plummeting. With high interest rates, solar no longer makes economic sense. Its more expensive than ever. Many solar installers are facing bankruptcy because the market has collapsed.
  • justinzollars 3y ago
    People are downvoting this, but from Tesla earnings today "Solar deployments declined on a sequential and YoY basis to 41 MW. Downward pressure on solar demand continued into Q4 as interest rates have remained high." This isn't an opinion, this is a fact. You could also compare the cost of capital between 3% and 10% and derive a cost per kwh.
    • Veserv 3y ago
      The failures of a tiny player like Tesla Solar are totally unrelated to US solar photovoltaic (PV) capacity. From 2021 to 2022 solar PV went from ~161,499 GWh to ~202,080 GWh of net generation (~25.1% increase) [1]. Utility scale went from 112,335 GWh to 140,798 GWh (~25.3% increase) [2] and personal/small scale solar PV went from ~49,164 GWh to ~61,282 GWh (~24.6% increase). New solar PV accounts for 11,058 MW of the total 31,692 MW (~34.8%) capacity additions for 2022 [3] and 24,545 MW of the total 51,490 MW (~47.6%) capacity additions that were planned for 2023 [4]. Tesla Solar accounts for ~1/5 of 1% of solar installation capacity, so it is hardly relevant compared to actual solar energy companies. [1] https://www.eia.gov/electricity/annual/html/epa_03_01_a.html https://www.eia.gov/electricity/annual/html/epa_03_01_a.html [2] Utility Scale Solar includes non-PV, Utility Scale PV numbers derived by subtracting Small Scale Solar Photovoltaic from Estimated Total Solar Photovoltaic [3] https://www.eia.gov/electricity/annual/html/epa_04_06.html https://www.eia.gov/electricity/annual/html/epa_04_06.html [4] https://www.eia.gov/electricity/annual/html/epa_04_05.html https://www.eia.gov/electricity/annual/html/epa_04_05.html
      • justinzollars 3y ago
        What is the cost of a $50,000 at 10% interest vs the cost of $50,000 at 2.5% interest over 10 years? Money is not free. Solar is now expensive: [1] https://www.cnet.com/home/energy-and-utilities/high-interest-rates-are-making-solar-leases-more-appealing/ https://www.cnet.com/home/energy-and-utilities/high-interest... [2] https://www.bloomberg.com/news/newsletters/2023-11-03/investors-sour-on-solar-sector-hurt-by-high-interest-rates https://www.bloomberg.com/news/newsletters/2023-11-03/invest... [3] https://finance.yahoo.com/news/solar-stocks-get-hit-as-rising-interest-rates-weigh-on-demand-183911358.html https://finance.yahoo.com/news/solar-stocks-get-hit-as-risin... [4] https://www.nytimes.com/2023/12/05/climate/renewable-energy-inflation-climate-cop28.html https://www.nytimes.com/2023/12/05/climate/renewable-energy-... [5] https://www.woodmac.com/news/opinion/high-interest-rates-impede-the-residential-solar-market-boom/ https://www.woodmac.com/news/opinion/high-interest-rates-imp... [6] https://www.ft.com/content/07443afb-b935-492d-8711-8c47e4353c59 https://www.ft.com/content/07443afb-b935-492d-8711-8c47e4353... [7] https://time.com/6281021/renewable-energy-interest-rates/ https://time.com/6281021/renewable-energy-interest-rates/ [8] https://www.fool.com/investing/2024/01/13/why-solar-energy-stocks-dropped-like-a-rock-last-y/ https://www.fool.com/investing/2024/01/13/why-solar-energy-s... [9] https://www.solarpowerworldonline.com/2024/01/high-interest-rates-and-other-issues-threaten-the-residential-solar-market/ https://www.solarpowerworldonline.com/2024/01/high-interest-... [10] https://www.newsweek.com/high-interest-rates-impact-solar-energy-biden-administration-inflation-reduction-act-1840859 https://www.newsweek.com/high-interest-rates-impact-solar-en...
• darth_avocado 3y ago
  It's like trying to use a hammer to screw some bolts. The priority should be sustainable development. We have enough water, just not great usage. The water infrastructure we have today is aged and needs to expand to allow for the population growth the country has seen. On top of that, we are expanding cities in parts of the country where water is scarce. We are growing water intensive crops in parts of the country that does not have water for it. We are also mismanaging the largest watershed in the country: the Missisippi. Just focus on these problems than creating other problems with desalination.
  • jvanderbot 3y ago
    93 billion gallons of fresh water falls on Los Angeles every year. (12 inches / y over the whole surface area[1]) They have ~2 million households[2], and a household uses an average of 3,000 g/m or 36,000 g/y/h or about 80 billion gallons / y for all households. Huge coincidence, that's pretty close to balanced out. And yet, we shuffle the rainfall to the ocean and pray for snowpack in the mountains and protest Nestle and Almond farmers. 1. https://www.wolframalpha.com/input?i=%28%2812+inches+*+los+angeles+surface+area%29+in+gallons+%29 https://www.wolframalpha.com/input?i=%28%2812+inches+*+los+a... 2. https://www.wolframalpha.com/input?i=households+in+los+angeles https://www.wolframalpha.com/input?i=households+in+los+angel...
    • donkeysquid 3y ago
      Only a fraction of that can be captured
      • persolb 3y ago
        I’d agree for a lot of places heavy on greenery… but LA? The city itself seems to have a very small percentage of greenery. I’m assuming the rest is mostly captured via sewers just to prevent flooding.
        • jvanderbot 3y ago
          This is true. A better designed city could capture more.
• isk517 3y ago
  Cool, out of everything in Star Wars it turns out moisture farming was the thing that would make it to real life.
• voisin 3y ago
  And cover existing canals with solar to reduce evaporation!
• nerdbert 3y ago
  Desalination means killing some ecosystem, wherever you choose to dump the brine, with waste salt.