Underground storage of compressed hydrogen or compressed air can deliver backup and firming supply, account for seasonal changes in load and provide strategic reserves of energy to call on if there is a risk of system outage. Compressed hydrogen has very high energy density.
[pdf] Building-integrated photovoltaics generate solar electricity and work as a structural part of a building. Today, most BIPV products are designed for large commercial buildings, like an apartment complex or community center.
[pdf] Energy can also be stored by changing how we use the devices we already have. For example, by heating or cooling a building before an anticipated peak of electrical demand, the building can “store” that t.
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