Re:Why Is Hydroelectricity So Green, and yet Unfashionable?
by WJW on Thursday October 27, 2022 @04:33PM
(#33363639)
No it's mostly the chemical energy in the stored hydrogen, pressure is only a small part of it (though they might insert some expander turbine somewhere in there). Pretty similar to how you'd rate a natural gas storage facility.
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Re:Why Is Hydroelectricity So Green, and yet Unfashionable?
by pfdietz on Thursday October 27, 2022 @10:35PM
(#33366902)
It should be noted that the energy stored in the pressure of gas is zero. All the energy of an ideal gas is the kinetic energy (and rotational/vibrational energy) of its molecules, which is thermal energy. Internal energy of an ideal gas is independent of pressure.
What compressed gas storage does is (aside from combustion energy of a fuel gas) to provide not a store of energy, but a store of reduced entropy, enabling otherwise unusable amounts of heat to be converted to work.