Power storage is currently the Achilles’ heel of the renewable energy sector.  With the exception of hydropower and geothermal, clean power production is intermittent, hence supply does not always correspond to when there is demand.

Power storage solutions include chemical batteries, capacitor batteries, hydrogen, and flywheels.  Nothing cost effective has come onto the market yet that stores large quantities of electricity, let alone the smaller quantities needed by electric vehicles.

Research and development for batteries is fast and furious these days, because whoever wins the race has a $500 billion dollar opportunity ahead.  The objective is to make a battery that is inexpensive, recyclable, and lightweight, which also has a long life, a fast charge, and a fast discharge.