3 ms·

Pumped hydro storage is approximately cost competitive with new nuclear. It depends on ease of incentives, building permits and finance mechanisms available for

by mayama 3y ago

Pumped hydro storage is approximately cost competitive with new nuclear. It depends on ease of incentives, building permits and finance mechanisms available for building new hydro vs nuclear. Estimated LCOE of new hydro in India for example is Rs9/kwh(~$100/Mwh) which is comparable to new nuclear estimates of $55-90/Mwh. China is also building pumped hydro at good pace. And pumped hydro doesn't have to fight entrenched anti-nuclear lobby while doing it. US and EU storage incentives encourage battery storage schemes over pumped hydro though. They either expect cost of battery storage to become less than pumped hydro shortly, or the lack of construction firms lobbying for pumped hydro is making battery the prominent storage option. https://energy.economictimes.indiatimes.com/news/renewable/timely-implementation-of-market-reforms-key-to-improve-financial-viability-of-pumped-hydro-storage-icra/99779703 https://energy.economictimes.indiatimes.com/news/renewable/t...

Manuel_D 3y ago
Pumped hydro is geographically limited. You might as well say we should just build more dams to decarbonize the electric grid.
- mayama 3y ago
  Offriver closed loop pumped hydro just needs two football size fields hundreds of meter apart in elevation. Most continents have plenty of suitable locations for PHS, though they are distributed unevenly. According to the paper, there are 600k feasible locations for PHS world wide, or capacity to store 70% of global energy demand in 2017. https://www.nature.com/articles/s41467-020-14555-y https://www.nature.com/articles/s41467-020-14555-y
  - Manuel_D 3y ago
    > Offriver closed loop pumped hydro just needs two football size fields hundreds of meter apart in elevation A football field sized reservoir isn't going to hold much water unless it's deep. Realistic pumped hydro sites are much larger than 500 square meters. And those two reservoirs can't be too far apart, because excess lateral distance reduces output and increases the energy required to refill it. It also needs to be close to a source of water in order to fill the reservoir and refill any loss due to evaporation. It also needs to be close to a major highway otherwise the costs of construction will be immense because of the long distance that materials and equipment must be shipped. This is particularly problematic because most pumped hydro potential is in mountainous terrain where transportation is expensive. And lastly, this site has to be close to places that have energy demand, otherwise you'll need to build miles and miles of transmission lines. This is also a problem because the places that have pumped hydro potential also have hydroelectric potential, and usually already generate electricity from dams. Norway and Brazil have huge pumped hydro potential, but already generate most electricity from dams. The conditions for a viable pumped hydro sites are much more narrow than "two football field sized reservoir a few hundred meters apart in elevation". The paper you cited just ran an algorithm over a terrain height map. It did not attempt to account for accessibility. Good luck developing the immense pumped hydro potential in Tibet. Pumped hydro would be great if we could teleport concrete, excavators, and turbo machinery into some of the most remote parts of the world. But unfortunately this is not in our capabilities.
    - adrianN 3y ago
      Even if the 70% of global energy demand in 2017 estimate is off by a factor of five or so, that's still plenty of storage to cover for renewable intermittency.
      - Manuel_D 3y ago
        I wouldn't be surprised if less than 1% of the identified hydroelectric sites were viable to build at all, and 0.1% were more cost competitive than batteries. Huge amounts of the identified hydropower sites are located in Tibet, which is far too remote to conduct big construction projects. Another big region with hydro electric storage potential is Brazil. But they already generate almost all of their electricity from renewables and they don't need pumped hydro. Again, the paper you cited just ran an algorithm over a height map. There was zero consideration of proximity to transportation, proximity to energy demand, and proximity to water to fill the reservoirs.
        defrost 3y ago
        There are other fun options, a number already tested and being expanded upon. China is building several "gravity towers" (different design to [1] but same concept), Australia is designing third generation (after a 1MW test pilot, and current 288MWh plant under construction) high temperature molten salt thermal energy storage tanks to night time buffer solar plants used to produce green methanol for use as a sustainable shipping fuel. [1] https://www.wired.com/story/energy-vault-gravity-storage/ https://www.wired.com/story/energy-vault-gravity-storage/ [2] https://reneweconomy.com.au/australias-biggest-solar-thermal-plant-takes-big-step-forward-with-digital-twin/ https://reneweconomy.com.au/australias-biggest-solar-thermal...
        Manuel_D 3y ago
        None of these have actually been used for grid storage. Heated sand has been used for district heating, but electric generation is more challenging because it requires higher temperature gradients. There's plenty of other ideas people are pursing: hydrogen electrolysis, compressed air, giant flywheels, ammonia, I could go on. Why are people exploring all these alternative energy storage methods? Because grid storage is not feasible with current storage options. We're still looking for the silver bullet to solve grid storage. Will these new ideas yield storage at lower cost than the existing systems? Maybe, maybe not. A grid powered by primarily intermittent sources is viable if such a silver bullet is found, but that's a pretty big if to bet the future of the electric grid on. A very realistic outlook for wind and solar is that we saturate peak production, waste a ton of excess electricity, and keep burning fossil fuels because the silver bullet never materializes.

by mayama 3y ago

Manuel_D 3y ago

Pumped hydro is geographically limited. You might as well say we should just build more dams to decarbonize the electric grid.

mayama 3y ago
Offriver closed loop pumped hydro just needs two football size fields hundreds of meter apart in elevation. Most continents have plenty of suitable locations for PHS, though they are distributed unevenly. According to the paper, there are 600k feasible locations for PHS world wide, or capacity to store 70% of global energy demand in 2017. https://www.nature.com/articles/s41467-020-14555-y https://www.nature.com/articles/s41467-020-14555-y
- Manuel_D 3y ago
  > Offriver closed loop pumped hydro just needs two football size fields hundreds of meter apart in elevation A football field sized reservoir isn't going to hold much water unless it's deep. Realistic pumped hydro sites are much larger than 500 square meters. And those two reservoirs can't be too far apart, because excess lateral distance reduces output and increases the energy required to refill it. It also needs to be close to a source of water in order to fill the reservoir and refill any loss due to evaporation. It also needs to be close to a major highway otherwise the costs of construction will be immense because of the long distance that materials and equipment must be shipped. This is particularly problematic because most pumped hydro potential is in mountainous terrain where transportation is expensive. And lastly, this site has to be close to places that have energy demand, otherwise you'll need to build miles and miles of transmission lines. This is also a problem because the places that have pumped hydro potential also have hydroelectric potential, and usually already generate electricity from dams. Norway and Brazil have huge pumped hydro potential, but already generate most electricity from dams. The conditions for a viable pumped hydro sites are much more narrow than "two football field sized reservoir a few hundred meters apart in elevation". The paper you cited just ran an algorithm over a terrain height map. It did not attempt to account for accessibility. Good luck developing the immense pumped hydro potential in Tibet. Pumped hydro would be great if we could teleport concrete, excavators, and turbo machinery into some of the most remote parts of the world. But unfortunately this is not in our capabilities.
  - adrianN 3y ago
    Even if the 70% of global energy demand in 2017 estimate is off by a factor of five or so, that's still plenty of storage to cover for renewable intermittency.
    - Manuel_D 3y ago
      I wouldn't be surprised if less than 1% of the identified hydroelectric sites were viable to build at all, and 0.1% were more cost competitive than batteries. Huge amounts of the identified hydropower sites are located in Tibet, which is far too remote to conduct big construction projects. Another big region with hydro electric storage potential is Brazil. But they already generate almost all of their electricity from renewables and they don't need pumped hydro. Again, the paper you cited just ran an algorithm over a height map. There was zero consideration of proximity to transportation, proximity to energy demand, and proximity to water to fill the reservoirs.
      - defrost 3y ago
        There are other fun options, a number already tested and being expanded upon. China is building several "gravity towers" (different design to [1] but same concept), Australia is designing third generation (after a 1MW test pilot, and current 288MWh plant under construction) high temperature molten salt thermal energy storage tanks to night time buffer solar plants used to produce green methanol for use as a sustainable shipping fuel. [1] https://www.wired.com/story/energy-vault-gravity-storage/ https://www.wired.com/story/energy-vault-gravity-storage/ [2] https://reneweconomy.com.au/australias-biggest-solar-thermal-plant-takes-big-step-forward-with-digital-twin/ https://reneweconomy.com.au/australias-biggest-solar-thermal...
        Manuel_D 3y ago
        None of these have actually been used for grid storage. Heated sand has been used for district heating, but electric generation is more challenging because it requires higher temperature gradients. There's plenty of other ideas people are pursing: hydrogen electrolysis, compressed air, giant flywheels, ammonia, I could go on. Why are people exploring all these alternative energy storage methods? Because grid storage is not feasible with current storage options. We're still looking for the silver bullet to solve grid storage. Will these new ideas yield storage at lower cost than the existing systems? Maybe, maybe not. A grid powered by primarily intermittent sources is viable if such a silver bullet is found, but that's a pretty big if to bet the future of the electric grid on. A very realistic outlook for wind and solar is that we saturate peak production, waste a ton of excess electricity, and keep burning fossil fuels because the silver bullet never materializes.