A toilet cistern contains around ten litres of water, and people tend to flush around three times per day, on average. If all 7 billion people on earth were to do this, the result would be a serious water shortage.
Energy storage comes in all shapes and sizes. Condensers are convenient for peak storage, but they are exhausted within a few seconds. The same applies to flywheels. Water storage in reservoir lakes and pressurised gas storage in underground reservoirs can provide a buffer of several hours of energy use. Batteries and accumulators can even store energy for weeks.
People can be strange creatures, as ergonomics expert Professor Peter Vink (Industrial Design Engineering) knows. They will sit in tight and uncomfortable seating to save money, complain about it in surveys and then do it all over again. These are the enigmas of environmental ergonomics.