Erik van't Woud / EPA
An ultra-efficient vehicle driven by a Spanish team drives the course of the Shell Eco-marathon in Rotterdam, The Netherlands on May 17. During the event students from all over Europe test their accumulated knowledge of energy-efficient driving with cars that can drive as far as possible on minimal fuel.
Erik Van't Woud / EPA
An Italian team works on their vehicle during the Shell Eco-marathon in Rotterdam, The Netherlands on May 17.
Jiri Buller / AP
A vehicle running on solar power races on day two of the Shell Eco-marathon Challenge in Rotterdam, The Netherlands on Thursday, May 17. Teams from universities all over Europe have brought their energy efficient cars to compete in the challenge.