Begun in 2011 as National Plug In Day, this is a "nationwide celebration to heighten awareness of today's widespread availability of plug-in vehicles and highlight the benefits of all-electric and plug-in hybrid-electric cars, trucks, motorcycles, and more."
2016: Saturday, Sept. 10 - Sunday, Sept. 18
2017: Saturday, Sept 9 - Sunday, Sept 17
(Week after Labor Day [?] starting on Saturday after Labor Day)