In order to cut its carbon emissions by 50 percent in a little more than a decade, Washington DC is passing a new law that calls for 100 percent renewable electricity by 2032. The deadline is 13 years earlier than those in California or Hawaii, which are also moving to 100 percent renewable energy. On top of that, all city buses, taxis, limos, or other privately owned fleets with 50 passengers or more will have to use zero-emission vehicles as of 2045.