“At the current price of $66 per barrel (for crude oil), with no bottom yet in sight, the economics of electric vehicles to the consumer have become significantly less attractive in just the past few months….Declining oil prices and the increase in energy supply caused by the development of shale gas reserves threaten to halt any momentum that may have been achieved in recent years when oil was trading above $100 per barrel. 

— Jack Perkowski, Forbes, Electric Cars: A Review Of 2014