Individual industries will use energy as LJJUZ] efficiently as it is economical to do so, and there are several incentives to improve the efficiency of energy consumption. To illustrate, consider the selection of a new water pump. The pump is to operate 800 hours per year. Pump A costs $2,000, has an overall efficiency of 82.06%, and it delivers 11 hp. The other available alternative, pump B, costs $1,000, has an overall efficiency of 45.13%, and delivers 12.1 hp. Both pumps have a useful life of five years and will be sold at that time. (Remember 1 hp = 0.746 kW.)
Pump A will use SL depreciation over five years with an estimated SV of zero. Pump B will use the MACRS depreciation method with a class life of three years. After five years, pump A has an actual market value of $400, and pump B has an actual market value of $200.
Using the IRR method on the after-tax cash flows and a before-tax MARR of 16.67%, is the incremental investment in pump A economically justifiable? The effective income tax rate is 40%. The cost of electricity is $0.05/kWh, and the pumps are subject to a study period of five years.