Richard Taylor (physics teacher at Hockaday School, Dallas, TX), recently bought an all-electric Chevrolet Volt. He quickly used our Watts Up Pro to monitor the charging cycle. Here is a graph of charging power vs. time for the Volt after Richard drove it 26.7 miles (43.0 km).

Charging at a fairly constant current and voltage drew about 1.3 kW for over 6 hours. The integral shows that this is 9.25 KwH, which would cost about a dollar in most parts of the U.S.