Electric vehicle (EV) sales spike leading up to the expiration date of incentives, then drop sharply afterward, writes Earl J. Ritchie, a lecturer within the Department of Construction Management at the University of Houston. Ritchie cites such spikes and slumps in the Netherlands and China. California counts for half of U.S. EV sales and offers state and local incentives in addition to the federal tax credit and the state's complicated zero-emission vehicle (ZEV) mandate, he said.   Click for article