A miles per kWh figure is used to calculate electric car efficiency. Understanding and comparing these numbers could save you ...

Armed with 50 cents a kilowatt hour, her company ran an analysis of the numbers, and concluded that a Think City (a small, two-seat battery car) would still be operated at 12 cents a mile, versus ...

The kilowatt hour, or kilowatt-hour, (symbol kW·h, kW h or kWh) is a unit of energy equal to 1000 watt hours or 3.6 megajoules. For constant power, energy in watt hours is the product of power in ...

The kWh tells us nothing about when energy is used, she says, while alternatives like the kilowatt-hour at peak time (kWhaPT) or the kilowatt-hour outside peak time (kWhoPT) have not caught on.