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Is the idea to use excess solar power to desalinate salt water instead of mine crypto currency? At a high level that seems smart. It seems like the general id

Is the idea to use excess solar power to desalinate salt water instead of mine crypto currency? At a high level that seems smart. It seems like the general idea is to build out excess capacity on the desalinization side and run the desalinization plant at less than full throughput during peak consumer demand (i.e. peak of the duck curve?).

mdale 3y ago
Lol. Almost like making drinking water and water that can be used to grow food is a better use of energy than boiling a small ocean of water on math designed to create artificial scarcity :)
dragontamer 3y ago
The opposite. The various policies we have are for Aluminum Smelting plants, Desal, and other heavy-electricity industries to use excess solar (or nuclear) power during peak-energy times, and to turn off during peak-usage times to help balance the grid. On an individual level, we might be able to even do this for air-conditioning, washing machines, or car-charging (if you have a PHEV or EV). Cryptocoins then perverted the models we created to earn money from this through mining (using energy during peak-energy and turning off during peak-usage). But the "intent" for those laws has always been for industry and/or individual grid-level issues. -------------- For low-utilization machines (ex: washing machines and dryers), this makes perfect sense. The main issue is that for high-utilization machines (ie: all industry wishes to run at 100%, rather than 80% or 50%), you end up doubling or more the cost of CapEx. Ex: You'll need twice as many Desal plants if they only operate during the most efficient 50% of times during the week. Which might be worthwhile, but you have to run the math. Every hour these plants are shutdown for power-saving purposes is an hour that they are sitting away / depreciating.
- vlovich123 3y ago
  I can’t imagine that’s how industries could actually run. I think they can benefit from cheaper costs to absorb excess electricity or reduce capacity slightly when it gets too expensive, but shutting down an aluminum smelting plant seems like a non-starter as they need to run constantly 24/7 and require long startup/shutdown times. Same goes for desal - you’re not going to economically produce sufficient amounts of water just trying to time the energy grid. https://www.reddit.com/r/AskEngineers/comments/3g78nj/are_aluminium_smelters_switching_to_daytime/ https://www.reddit.com/r/AskEngineers/comments/3g78nj/are_al...
  - dragontamer 3y ago
    I agree. Nonetheless, some industry are willing to give it a test to see how feasible it is. https://www.lightmetalage.com/news/industry-news/smelting/trimet-starts-trial-operation-of-its-virtual-battery/ https://www.lightmetalage.com/news/industry-news/smelting/tr... > “We have reinvented the electrolysis process for the production of aluminium. For the first time, we will be able to vary the energy supply during operation significantly. This will allow us to react to changes in the electricity supply, which will benefit the power supply to households in Essen,” says Philipp Schlüter, CEO of TRIMET. “As an aluminium producer, we are naturally an energy-intensive company. As such, however, we are also a valuable partner for the energy revolution.” > The €36 million trial installation converted a total of 120 furnaces in hall one of its Essen plant, which will be able to consume either 25% more or 25% less energy for up to 48 hours. The energy requirement can also be reduced to zero for up to an hour, if necessary. This means up to 2,000 megawatt hours of electricity can be stored for use in the energy revolution. ----------- It requires new smelters, new software, new engineers. Its all very expensive. But it might be worthwhile. Just don't go like... crazy... with the idea right? There's downsides, but the upsides are immense. Keep an eye on the costs and practicality, and give it a test. It might be worthwhile. That's my outlook anyway. Maybe Aluminum specifically is run too close to 100% utilization to be useful (we do have a very predictable amount of Aluminum...), but maybe other industries have a more start/stop and feast/famine kind of setup that would benefit from off-hours automation for energy price optimizations and/or even grid-tie stabilization. But there are _real_ Aluminum plants giving this idea a test. So this isn't "vaporware" or even "theoretical". This is a real test occurring today. ------------- We have to ask ourselves: is a 2GW-hr battery the best thing to build? What if Aluminum-smelters could instead vary their load by +/- 25% with this new software/manufacturing mechanism? What costs more, the 2GW-hr battery or this software + manufacturing change to Aluminum plants? In both cases, we get 2GW-hrs of "energy storage". EDIT: IE, varying your load each day is a form of energy storage that should be considered by members of society. It may very well be cheaper to achieve 2GW-hrs of virtual energy storage by upgrading industry, rather than trying to build impossibly huge amounts of Li-ion batteries.
    - vlovich123 3y ago
- breischl 3y ago
  >we might be able to even do this for air-conditioning, washing machines, or car-charging (if you have a PHEV or EV). No _might_ about it, this currently happens for A/C, and is just getting going for car charging (see EV Managed Charging as a category). Also some functions of commercial/industrial facilities that can be ramped more easily, eg shut off half of the hallway lighting in an office building. I think I recall things like rock crushers being turned off, but I might be misremembering that.
  - __MatrixMan__ 3y ago
    Unfortunately, solar panels get less efficient when hot, which is when your AC demand increases. Ideally you could offset this by having people who aren't well positioned for panels do energy storage: Buy in the morning, sell back in the afternoon. Practically I don't think the utility companies are going to cut them in on a big enough part of the profits to incentivize them to do so.
    - breischl 3y ago
      Sorry I stated my original point poorly, and it wasn't exactly what you were saying. My bad. Demand response for A/C tends to look more like pre-cooling before the hottest hours, then reduce demand during the hottest hours. So it's not about shifting demand towards maximum production, but rather shifting demand away from the demand peak (aka, peak shaving). So it's similar but a little different. >Practically I don't think the utility companies are going to cut them in on a big enough part of the profits to incentivize them to do so. The commercial version of what I stated in the previous paragraph (ie, demand response/peak shaving) empirically already happens, and has non-trivial dollars attached to it. Again, maybe not exactly what you're talking about, but it rhymes.
    - duckmysick 3y ago
      > Unfortunately, solar panels get less efficient when hot, Less efficient by what factor?
      - edent 3y ago
- F-W-M 3y ago
  Energy costs vary not only over the day but per quarter hour in each hour, e.g. during the morning the last quarter is cheaper than the first for each hour. So you don't necessarily have to shut down the machines, maybe you can just move the most energy expensive phase into another quarter. If you are brewing beer you have times where you have to heat it and times where it needs to sit at a given temperature. Try to optimize the process to heat during cheaper quarter hours.
  - stephen_g 3y ago
    In Australia we've moved all the way to five-minute (!) settlement in our electricity market. Used to be 30 minutes but they switched in 2021 to give better price signals for very fast response technology like battery banks, as well as the demand response.
    - F-W-M 3y ago
      Do you have a auction + continuous market as well? With same or with different granularity? Europe has an day-ahead auction with 1h products and continuous trading with quarter hours as the smallest product (still varying from country to country).
- patall 3y ago
  You assume that it is all linear which it may not be. Osmosis at power P may produce X litres of water per time unit while osmosis at power 4P may produce only 2X litres per time unit. And thus be viable only when the electricity price is N times lower.
- reactordev 3y ago
  >”On an individual level, we might be able to even do this” At Tendril, we did this in 2017. We called it Orchestrated Energy.
- jon_richards 3y ago
  The most egregious broken window fallacy I’ve heard is a vc claiming that cryptocurrency lets you “virtually” transfer energy from areas with low prices to areas with high prices (without power lines!).

mdale 3y ago

Lol. Almost like making drinking water and water that can be used to grow food is a better use of energy than boiling a small ocean of water on math designed to create artificial scarcity :)

dragontamer 3y ago

The opposite. The various policies we have are for Aluminum Smelting plants, Desal, and other heavy-electricity industries to use excess solar (or nuclear) power during peak-energy times, and to turn off during peak-usage times to help balance the grid. On an individual level, we might be able to even do this for air-conditioning, washing machines, or car-charging (if you have a PHEV or EV). Cryptocoins then perverted the models we created to earn money from this through mining (using energy during peak-energy and turning off during peak-usage). But the "intent" for those laws has always been for industry and/or individual grid-level issues. -------------- For low-utilization machines (ex: washing machines and dryers), this makes perfect sense. The main issue is that for high-utilization machines (ie: all industry wishes to run at 100%, rather than 80% or 50%), you end up doubling or more the cost of CapEx. Ex: You'll need twice as many Desal plants if they only operate during the most efficient 50% of times during the week. Which might be worthwhile, but you have to run the math. Every hour these plants are shutdown for power-saving purposes is an hour that they are sitting away / depreciating.

vlovich123 3y ago
I can’t imagine that’s how industries could actually run. I think they can benefit from cheaper costs to absorb excess electricity or reduce capacity slightly when it gets too expensive, but shutting down an aluminum smelting plant seems like a non-starter as they need to run constantly 24/7 and require long startup/shutdown times. Same goes for desal - you’re not going to economically produce sufficient amounts of water just trying to time the energy grid. https://www.reddit.com/r/AskEngineers/comments/3g78nj/are_aluminium_smelters_switching_to_daytime/ https://www.reddit.com/r/AskEngineers/comments/3g78nj/are_al...
- dragontamer 3y ago
  I agree. Nonetheless, some industry are willing to give it a test to see how feasible it is. https://www.lightmetalage.com/news/industry-news/smelting/trimet-starts-trial-operation-of-its-virtual-battery/ https://www.lightmetalage.com/news/industry-news/smelting/tr... > “We have reinvented the electrolysis process for the production of aluminium. For the first time, we will be able to vary the energy supply during operation significantly. This will allow us to react to changes in the electricity supply, which will benefit the power supply to households in Essen,” says Philipp Schlüter, CEO of TRIMET. “As an aluminium producer, we are naturally an energy-intensive company. As such, however, we are also a valuable partner for the energy revolution.” > The €36 million trial installation converted a total of 120 furnaces in hall one of its Essen plant, which will be able to consume either 25% more or 25% less energy for up to 48 hours. The energy requirement can also be reduced to zero for up to an hour, if necessary. This means up to 2,000 megawatt hours of electricity can be stored for use in the energy revolution. ----------- It requires new smelters, new software, new engineers. Its all very expensive. But it might be worthwhile. Just don't go like... crazy... with the idea right? There's downsides, but the upsides are immense. Keep an eye on the costs and practicality, and give it a test. It might be worthwhile. That's my outlook anyway. Maybe Aluminum specifically is run too close to 100% utilization to be useful (we do have a very predictable amount of Aluminum...), but maybe other industries have a more start/stop and feast/famine kind of setup that would benefit from off-hours automation for energy price optimizations and/or even grid-tie stabilization. But there are _real_ Aluminum plants giving this idea a test. So this isn't "vaporware" or even "theoretical". This is a real test occurring today. ------------- We have to ask ourselves: is a 2GW-hr battery the best thing to build? What if Aluminum-smelters could instead vary their load by +/- 25% with this new software/manufacturing mechanism? What costs more, the 2GW-hr battery or this software + manufacturing change to Aluminum plants? In both cases, we get 2GW-hrs of "energy storage". EDIT: IE, varying your load each day is a form of energy storage that should be considered by members of society. It may very well be cheaper to achieve 2GW-hrs of virtual energy storage by upgrading industry, rather than trying to build impossibly huge amounts of Li-ion batteries.
  - vlovich123 3y ago
breischl 3y ago
>we might be able to even do this for air-conditioning, washing machines, or car-charging (if you have a PHEV or EV). No _might_ about it, this currently happens for A/C, and is just getting going for car charging (see EV Managed Charging as a category). Also some functions of commercial/industrial facilities that can be ramped more easily, eg shut off half of the hallway lighting in an office building. I think I recall things like rock crushers being turned off, but I might be misremembering that.
- __MatrixMan__ 3y ago
  Unfortunately, solar panels get less efficient when hot, which is when your AC demand increases. Ideally you could offset this by having people who aren't well positioned for panels do energy storage: Buy in the morning, sell back in the afternoon. Practically I don't think the utility companies are going to cut them in on a big enough part of the profits to incentivize them to do so.
  - breischl 3y ago
    Sorry I stated my original point poorly, and it wasn't exactly what you were saying. My bad. Demand response for A/C tends to look more like pre-cooling before the hottest hours, then reduce demand during the hottest hours. So it's not about shifting demand towards maximum production, but rather shifting demand away from the demand peak (aka, peak shaving). So it's similar but a little different. >Practically I don't think the utility companies are going to cut them in on a big enough part of the profits to incentivize them to do so. The commercial version of what I stated in the previous paragraph (ie, demand response/peak shaving) empirically already happens, and has non-trivial dollars attached to it. Again, maybe not exactly what you're talking about, but it rhymes.
  - duckmysick 3y ago
    > Unfortunately, solar panels get less efficient when hot, Less efficient by what factor?
    - edent 3y ago
F-W-M 3y ago
Energy costs vary not only over the day but per quarter hour in each hour, e.g. during the morning the last quarter is cheaper than the first for each hour. So you don't necessarily have to shut down the machines, maybe you can just move the most energy expensive phase into another quarter. If you are brewing beer you have times where you have to heat it and times where it needs to sit at a given temperature. Try to optimize the process to heat during cheaper quarter hours.
- stephen_g 3y ago
  In Australia we've moved all the way to five-minute (!) settlement in our electricity market. Used to be 30 minutes but they switched in 2021 to give better price signals for very fast response technology like battery banks, as well as the demand response.
  - F-W-M 3y ago
    Do you have a auction + continuous market as well? With same or with different granularity? Europe has an day-ahead auction with 1h products and continuous trading with quarter hours as the smallest product (still varying from country to country).
patall 3y ago
You assume that it is all linear which it may not be. Osmosis at power P may produce X litres of water per time unit while osmosis at power 4P may produce only 2X litres per time unit. And thus be viable only when the electricity price is N times lower.
reactordev 3y ago
>”On an individual level, we might be able to even do this” At Tendril, we did this in 2017. We called it Orchestrated Energy.
jon_richards 3y ago
The most egregious broken window fallacy I’ve heard is a vc claiming that cryptocurrency lets you “virtually” transfer energy from areas with low prices to areas with high prices (without power lines!).