Note to players: Description acceptable. One technology for this purpose has an “advanced adiabatic” variant that has yet to achieve viability. Various devices that serve this purpose can be compared using a Ragone plot. One type of device used for this purpose relies on the formation (15[1])of a double layer on two coatings of activated carbon and is called an EDLC. Another (15[1])system for this purpose uses (15[1])magnetic bearings to (15[1])levitate a (*) flywheel. Round-trip efficiencies between 70-80% are achieved by “pumped” systems for this purpose, which (-5[1])hold water at two (10[1])different elevations (-5[1])to deal with load (10[1])fluctuations. (10[1])Technologies for this purpose (-5[1])are (-5[1])needed because, for many renewables, (10[1])peak demand and (-5[1])peak production (10[4])occur (-5[1])at different (10[1])times. For 10 points, name (10[1])this process (10[3])performed by hooking (10[1])up a power (10[1])plant to (10[2])a grid of rechargeable batteries. ■END■