Mechanical: Direct storage of potential or kinetic energy. Typically, pumped storage hydropower or compressed air energy storage (CAES) or flywheel. Thermal: Storage of excess energy as heat or cold for later usage. Can involve sensible (temperature change) or latent (phase change) thermal storage.
[pdf] Natural gas distributed energy systems have developed rapidly owing to their high efficiency, low environmental impact, high energy supply reliability, and good economic returns. As the main users of natural gas dis.
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