电能成本计算器及计算方法。
The energy E in kilowatt-hours (kWh) per day is equal to the power P in 瓦特 （瓦特） times number of usage hours per day t divided by 1000 watts per kilowatt:
E(kW小时/天) = P（瓦特） × t(小时/天) / 1000（瓦特/千瓦）
The energy cost per day in dollars is equal to the energy consumption E in kWh per day times the energy cost of 1 kWh in 分s/kWh divided by 100 cents per dollar:
成本（美元/天） = E(kW小时/天) × 成本(分/kWh) / 100(分/$)
