Stores surplus electricity by compressing air into a pressure vessel and recovers it later through an expander/air motor driving a generator. A non-electrochemical alternative to battery storage: longer service life, simpler and more repairable components, no lithium/rare-earth content. The open challenge at household scale is round-trip efficiency versus tank size (the source argues small high-efficiency designs are achievable but this is not yet a common, proven household product). Treat as low-maturity/experimental.
Note: Cost, carbon and footprint are rated against the other options for this same need, not in absolute terms.
Space for a pressure vessel/tank; pairs with a generation source such as a PV array.
No sizing or quantities: how much a technique yields, and how much a household needs, both depend on the build and the people, so the catalogue compares options rather than dimensioning them. It carries no bill of materials and no build sequence, and it is written for an oceanic, clay-soil climate (Normandy, France). Regulatory notes are indicative and need confirming locally.