While sales continue to grow, electric cars still represent a tiny fraction of the vehicles on the world's roads.
Perhaps that explains the proclivity of electric-car advocates to assemble them into ever-larger groups: It's a case of strength in numbers.
Last week, 507 electric cars gathered in Stuttgart, Germany--enough to break the Guinness World Record for the largest electric-vehicle parade in history.
The rally was organized by the World Advanced Vehicle Expedition (WAVE)--an electric-car advocacy group started by solar-energy promoter Louis Palmer, who made round-the-world trips in a solar-powered car in 2007 and 2008.
WAVE electric-car parade in Stuttgart, Germany.
Participants ranged from a Volkswagen Beetle and vintage 1963 Land Rover, both converted to electric power, as well as at least one Tesla Model and a Smart ForTwo Electric Drive from the Car2Go car-sharing service.
According to Transport Evolved, Guinness rules required all vehicles participating in the rally to be powered solely by electricity. Hence, plug-in hybrids and extended-range electric cars like the Chevrolet Volt and BMW i3 REx were not included.
The WAVE rally surpasses the 431-car record set in April by the National Advanced Transportation Center--a Canadian electric-car advocacy group.
The fleet of plug-in cars--assembled in a long parking lot on the Île Sainte-Hélène along the Saint Laurence River, in Montréal--included both battery-electric vehicles and plug-in hybrids.