## Energy cost calculation with formulas

#### Energy consumption calculation

The energy E in kilowatt-hours (kWh) per day is equal to the power P in watts (W) times number of usage hours per day t divided by 1000 watts per kilowatt:

*E*_{(kWh/day)} = *P*_{(W)} × *t*_{(h/day)} / 1000_{(W/kW)}

#### Energy cost calculation

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 cents/kWh divided by 100 cents per dollar:

Cost_{($/day)} = *E*_{(kWh/day)} × Cost_{(cent/kWh)} / 100_{(cent/$)}