Question

A particular home owner is tired of paying electric utility bills and wants to remove him/herself from the power grid. After reviewing the electrical bills for the past year, the home owner determines that his/her house uses 20kWh per day on average. The home owner wants to purchase a generator capable of meeting his/her electrical demands.

1. Estimate how much gasoline it would use in one 24-hour period. How much would it cost to operate per day assuming gas costs $2/gallon? How much per month? How does this compare to the cost that a utility charges if the rate is $0.12 per kWh?

2. After taking measurements, it is determined that the typical worst-case load draws 120 amps at 240 volts (stove, oven, clothes dryer, furnace all on at the same time). How much torque and horsepower would the engine have to supply at 1800RPM to meet this worst case load?

Answer 1