The eggs are a means of affordably and, with acceptable efficiency, storing large amounts of electrical energy for later use. Taking a familiar example, Los Angeles has a yearly average power demand of roughly 3,000 megawatts (maw). If we plan to supply the great city with eight hours of stored energy, they’ll need something like 24,000 mWh of it (3,000 mW x 8 hours). No such storage system at present exists, but a great many possible chemistries have been proposed by which to build it. Remember the rule: Business does nothing for nothing. Investors want to know their money will earn a competitive return, as compared with, say, hedge funds.