3 ms·
I'm not talking about physical size. I'm talking about cost and complexity. An air tank with a compressor pump at one end and a turbine at the other is simple,
by beat 11y ago
I'm not talking about physical size. I'm talking about cost and complexity. An air tank with a compressor pump at one end and a turbine at the other is simple, reliable, well-understood, off-the-shelf technology. How much energy can you store in an air tank that would fit on the back of a truck? Hook it up to another truck full of solar panels, and you have a local electric grid, capable of powering at least a few buildings, at very reasonable cost and minimal sophistication required for operation and maintenance.
- SilasX 11y agoScalability covers spatial scalability, and so necessarily involves talking about physical size relative to energy stored in this context.
- beat 11y agoIs that actually important, though? Does it mean inexpensive small-scale energy caching in off-grid areas is impossible? Would a truck-carried air tank (or bank of them) hooked to solar-powered compressors not actually work, or be cost-prohibitive? Size doesn't actually matter here.
- SilasX 11y agoBut it does. The Wikipedia numbers [1] give a mass density for compressed air storage of 40 kJ/kg and volume density of 8 kJ/L. That's 0.011 kWh/kJ or 0.0014 kWh/L. So a 10,000 L tank gets you only 14 kWh, or ~$1.50 worth of energy. [1] https://en.wikipedia.org/wiki/Compressed_air_energy_storage#Specific_energy.2C_energy_density_and_efficiency https://en.wikipedia.org/wiki/Compressed_air_energy_storage#...