A homeowner is currently using a natural gas furnace for heating the house in winter but he is considering replacing this system with a furnace burning wood pellets. The homeowner currently pays an average of $3000 per year for space heating. Using the values below, determine how much the homeowner will save from heating per year if he replaces the existing furnace with pellet burning furnace. Natural gas furnace: ηboiler = 0.90, Unit price = $1.35/therm (1 therm = 105,500 kJ) Wood pellet: HV = 20,000 kJ/kg, ηboiler = 0.80, Unit price = $0.15/kg