Using compressed air to store energy is simple and doesn't have the life cycle limits that batteries do.
However, *all* gasses when compressed become hotter. A significant portion of the energy put into the compression goes into that heat. If the compressed gas is allowed to cool, it loses a serious portion of its energy which shows up as a reduction in pressure.
This is made worse during its expansion in an engine - it cools to below ambient temperature so it doesn't expand as much as its original volume. Only if expanded isothermally will you get its stored energy back.
So you lose energy in compression *and* expansion unless each is either isothermal or you store the thermal energy. Making a pressure tank that keeps the heat in is a major thermal trick unless you drive the vehicle right away (in minutes).
Otherwise electrical storage is far more efficient.
If you want to reduce pollution and energy use, efficiency is of primary importance...
Ref: Any Thermodynamics 101 course.
Anytime someone claims a fundamental concept in physics is wrong, *they* are almost certainly in error. Either they don't understand what they think is wrong (such as applying Carnot's proof to cases where it doesn't apply) or their own alternatives (even the Wright brothers made propellors with efficiencies in the 70% range so getting four times that isn't going to happen).
This entire document is rife with such errors. Even the proposed heat engine is wrong - what happens when the gasses in it rise? They lose pressure and adiabatically lose temperature as well. The entire engine will stop due to lack of an effective temperature differential.
Sigh. So many such folks and so few comets...
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Using compressed air to store energy is simple and doesn't have the life cycle limits that batteries do. However, *all* gasses when compressed become hotter. A significant portion of the energy put into the compression goes into that heat. If the compressed gas is allowed to cool, it loses a serious portion of its energy which shows up as a reduction in pressure. This is made worse during its expansion in an engine - it cools to below ambient temperature so it doesn't expand as much as its original volume. Only if expanded isothermally will you get its stored energy back. So you lose energy in compression *and* expansion unless each is either isothermal or you store the thermal energy. Making a pressure tank that keeps the heat in is a major thermal trick unless you drive the vehicle right away (in minutes). Otherwise electrical storage is far more efficient. If you want to reduce pollution and energy use, efficiency is of primary importance... Ref: Any Thermodynamics 101 course.
Anytime someone claims a fundamental concept in physics is wrong, *they* are almost certainly in error. Either they don't understand what they think is wrong (such as applying Carnot's proof to cases where it doesn't apply) or their own alternatives (even the Wright brothers made propellors with efficiencies in the 70% range so getting four times that isn't going to happen). This entire document is rife with such errors. Even the proposed heat engine is wrong - what happens when the gasses in it rise? They lose pressure and adiabatically lose temperature as well. The entire engine will stop due to lack of an effective temperature differential. Sigh. So many such folks and so few comets...