My favorite "SciFi-Like" power storage concept is a PowerLoop [1]
Someone could take the old Superconducting Supercollider tunnel in Texas, put in the theoretical PowerLoop infrastructure for about $500m and then it would be able to store enough power for the entire state of Texas to operate for over a day. The money it would make on the arbitrage between cheap power generated from solar & wind and times where demand exceeded baseline generation capacities would pay for the system, according to the designer, within a few weeks.
Someone could take the old Superconducting Supercollider tunnel in Texas, put in the theoretical PowerLoop infrastructure for about $500m and then it would be able to store enough power for the entire state of Texas to operate for over a day. The money it would make on the arbitrage between cheap power generated from solar & wind and times where demand exceeded baseline generation capacities would pay for the system, according to the designer, within a few weeks.
[1] http://launchloop.com/PowerLoop