4 ms·

Consuming energy productively > storing it? Well, yeah...

by BiteCode_dev 3y ago

tantalor 3y ago
What's the difference
- vlovich123 3y ago
  Storing it lets you feed back that energy at a different time (e.g. night) but requires a lot of expensive hardware (i.e. batteries) + you have to deal with losses involved with storing & retrieving that energy. Consuming it directly doesn’t require batteries and desal plants are cheaper than battery plants + going to be fewer losses. It’s a stupid comparison though because the point of batteries is to get to net 0 and desal plants don’t help with that. But it’s not a great sign for renewables achieving net 0 at the grid level that a process that is so energy intensive for getting so little water out is a better use of electricity than batteries.
  - jeffbee 3y ago
    Desal plants do help by giving renewables something economically valuable to do in the spring when energy output is being wasted.
    - vlovich123 3y ago
      Only because you have to overbuild more solar capacity than you need to with nuclear/hydro/fossil fuel plants which have a more reliable method of operation.
  - toast0 3y ago
    If you live somewhere that desal is the way you get your drinking / irrigation water, it makes sense that rather than storing energy to run desal continuously you can run desal intermittently and store water. You already need infrastructure to store fresh water for later use, and storing water for later use is relatively low loss (depending on the scale --- outdoor reservoirs can have a lot of loss). There's always a question of capital costs, of course: does it make more sense to have a higher capacity plant with a lower duty cycle where the duty cycle that uses mostly off-peak priced energy, or a lower capacity plant with a higher duty cycle which uses on-peak priced energy much of the time. Most energy consumers don't care about getting to net 0, they want to pay less for energy, if energy is a large part of their input costs. Intermittent operations do help get to net 0 though --- if all energy intensive uses could handle intermittent operations, it allows for more intermittent generation. It certainly doesn't get you all the way though; there's lots of uses that won't work well without continuous energy.
    - vlovich123 3y ago
      If you read the article, this take actually is not true if you have a grid powered fully by renewables. It only makes sense when you have a hybrid grid where baseload is powered by fossil fuels and the arbitrage difference makes desal attractive. Note that a nuclear grid doesn’t have this problem & it has enough capacity to reliably power everything + continuously run desal. To run desal off of solar requires a much larger capacity installed because you have to make up the lack of 24/7 operation with excess capacity whereas something like nuclear can make up the production gap due to smaller excess capacity by running 24/7.
deleted 3y ago
[deleted]

Consuming energy productively > storing it? Well, yeah...

tantalor 3y ago

What's the difference

vlovich123 3y ago
Storing it lets you feed back that energy at a different time (e.g. night) but requires a lot of expensive hardware (i.e. batteries) + you have to deal with losses involved with storing & retrieving that energy. Consuming it directly doesn’t require batteries and desal plants are cheaper than battery plants + going to be fewer losses. It’s a stupid comparison though because the point of batteries is to get to net 0 and desal plants don’t help with that. But it’s not a great sign for renewables achieving net 0 at the grid level that a process that is so energy intensive for getting so little water out is a better use of electricity than batteries.
- jeffbee 3y ago
  Desal plants do help by giving renewables something economically valuable to do in the spring when energy output is being wasted.
  - vlovich123 3y ago
    Only because you have to overbuild more solar capacity than you need to with nuclear/hydro/fossil fuel plants which have a more reliable method of operation.
- toast0 3y ago
  If you live somewhere that desal is the way you get your drinking / irrigation water, it makes sense that rather than storing energy to run desal continuously you can run desal intermittently and store water. You already need infrastructure to store fresh water for later use, and storing water for later use is relatively low loss (depending on the scale --- outdoor reservoirs can have a lot of loss). There's always a question of capital costs, of course: does it make more sense to have a higher capacity plant with a lower duty cycle where the duty cycle that uses mostly off-peak priced energy, or a lower capacity plant with a higher duty cycle which uses on-peak priced energy much of the time. Most energy consumers don't care about getting to net 0, they want to pay less for energy, if energy is a large part of their input costs. Intermittent operations do help get to net 0 though --- if all energy intensive uses could handle intermittent operations, it allows for more intermittent generation. It certainly doesn't get you all the way though; there's lots of uses that won't work well without continuous energy.
  - vlovich123 3y ago
    If you read the article, this take actually is not true if you have a grid powered fully by renewables. It only makes sense when you have a hybrid grid where baseload is powered by fossil fuels and the arbitrage difference makes desal attractive. Note that a nuclear grid doesn’t have this problem & it has enough capacity to reliably power everything + continuously run desal. To run desal off of solar requires a much larger capacity installed because you have to make up the lack of 24/7 operation with excess capacity whereas something like nuclear can make up the production gap due to smaller excess capacity by running 24/7.

deleted 3y ago

[deleted]