6 ms·

They are a little more theoretical at this point but there is also compressed air and mechanical (concrete blocks lifted by a crane) storage as well.

adgjlsfhk1 5y ago
concrete blocks are a really stupid battery. It's just a worse version of pumped hydro.
- cure 5y ago
  It also has some significant advantages over hydro: can be built anywhere, requires a small fraction of the space, doesn't destroy vast landscapes by putting them under water.
  - adgjlsfhk1 5y ago
    concrete only is 2x more dense. To get the same amount of storage as pumped hydro, that means you need to use at least half as much space. If you see a cute design for lifting concrete that isn't about the same size as a lake, it's a scam.
    - jl6 5y ago
      Maybe concrete lifting facilities would be about the same size as a lake if you built thousands of them (one per small town?) and added all that mass up?
      - danans 5y ago
        You would pretty quickly lose any economies of scale if you had to replicate the motor/generator, hoisting mechanism, etc across thousands of lower capacity facilities. The whole idea behind concrete blocks is that the storage medium is common, cheap, and easy to scale up, but that ignores significant other challenges.
      - adgjlsfhk1 5y ago
        Even ignoring the space concerns, and just looking at the cost, it's completely nonviable. For example, the Grand Coulee Dam has been functioning for 80 years, has a 170 meter height, and holds 9 billion kg of water for a (construction) cost of 2 billion dollars (adjusted for inflation). If you compare that to a crane based system a single tower crane can (in optimal circumstances) reach a wide enough area to lift 500,000kg a similar height (I'm being extremely generous with this estimate). That crane will cost you well over 1 million dollars, will only last around 20 years, and you would need about 4000 of these cranes to have the same capacity. Putting this all together means that the cranes will cost 20x more than the hydro solution even if you ignore the much higher maintenance and operational costs. This is also assuming that the cost of 9 billion kg of concrete is negligible (which it isn't), and that you aren't going to need to replace blocks as they get smashed into each other (which you will). Also, the crane solution will have lower efficiency, won't work in high wind, and is utterly stupid for about 50 other more boring reasons.
- jodrellblank 5y ago
  Does that include this kind of design: https://www.siemensgamesa.com/en-int/newsroom/2019/06/190612-siemens-gamesa-inauguration-energy-system-thermal https://www.siemensgamesa.com/en-int/newsroom/2019/06/190612... > "The heat storage facility, which was ceremonially opened today in Hamburg-Altenwerder, contains around 1,000 tonnes of volcanic rock as an energy storage medium. It is fed with electrical energy converted into hot air by means of a resistance heater and a blower that heats the rock to 750°C. When demand peaks, ETES uses a steam turbine for the re-electrification of the stored energy. The ETES pilot plant can thus store up to 130 MWh of thermal energy for a week. In addition, the storage capacity of the system remains constant throughout the charging cycles."
  - zardo 5y ago
    Thermal storage of various sorts looks pretty reasonable. I think it's constructing towers or digging holes to store gravitational potential energy that's being dismissed.

adgjlsfhk1 5y ago

concrete blocks are a really stupid battery. It's just a worse version of pumped hydro.

cure 5y ago
It also has some significant advantages over hydro: can be built anywhere, requires a small fraction of the space, doesn't destroy vast landscapes by putting them under water.
- adgjlsfhk1 5y ago
  concrete only is 2x more dense. To get the same amount of storage as pumped hydro, that means you need to use at least half as much space. If you see a cute design for lifting concrete that isn't about the same size as a lake, it's a scam.
  - jl6 5y ago
    Maybe concrete lifting facilities would be about the same size as a lake if you built thousands of them (one per small town?) and added all that mass up?
    - danans 5y ago
      You would pretty quickly lose any economies of scale if you had to replicate the motor/generator, hoisting mechanism, etc across thousands of lower capacity facilities. The whole idea behind concrete blocks is that the storage medium is common, cheap, and easy to scale up, but that ignores significant other challenges.
    - adgjlsfhk1 5y ago
      Even ignoring the space concerns, and just looking at the cost, it's completely nonviable. For example, the Grand Coulee Dam has been functioning for 80 years, has a 170 meter height, and holds 9 billion kg of water for a (construction) cost of 2 billion dollars (adjusted for inflation). If you compare that to a crane based system a single tower crane can (in optimal circumstances) reach a wide enough area to lift 500,000kg a similar height (I'm being extremely generous with this estimate). That crane will cost you well over 1 million dollars, will only last around 20 years, and you would need about 4000 of these cranes to have the same capacity. Putting this all together means that the cranes will cost 20x more than the hydro solution even if you ignore the much higher maintenance and operational costs. This is also assuming that the cost of 9 billion kg of concrete is negligible (which it isn't), and that you aren't going to need to replace blocks as they get smashed into each other (which you will). Also, the crane solution will have lower efficiency, won't work in high wind, and is utterly stupid for about 50 other more boring reasons.
jodrellblank 5y ago
Does that include this kind of design: https://www.siemensgamesa.com/en-int/newsroom/2019/06/190612-siemens-gamesa-inauguration-energy-system-thermal https://www.siemensgamesa.com/en-int/newsroom/2019/06/190612... > "The heat storage facility, which was ceremonially opened today in Hamburg-Altenwerder, contains around 1,000 tonnes of volcanic rock as an energy storage medium. It is fed with electrical energy converted into hot air by means of a resistance heater and a blower that heats the rock to 750°C. When demand peaks, ETES uses a steam turbine for the re-electrification of the stored energy. The ETES pilot plant can thus store up to 130 MWh of thermal energy for a week. In addition, the storage capacity of the system remains constant throughout the charging cycles."
- zardo 5y ago
  Thermal storage of various sorts looks pretty reasonable. I think it's constructing towers or digging holes to store gravitational potential energy that's being dismissed.