In order to calculate the PPW of a system, information on the size of the system and system cost is needed. System size is measured in Kilowatts or kW. When figuring out the PPW, information on the amount of watts the system requires is needed.
To calculate the wattage, you take the kW and multiply by 1000 (1 kW = 1000 Watts).
To find the PPW, take the total system cost and divide it by the total watts of the system.
Example: System size is 5 kW, or 5,000 watts and the cost of the system is $20,000. Therefore, the PPW is $4.00.
5kW x 1,000 = 5,000 W
$20,000 / 5,000 W= $4.00/per watt
Difference between Net PPW and Gross System Cost PPW: The Net PPW is calculated AFTER rebates and credits are applied. Gross System Cost defined as the PPW after adders and dealer fees are added to the deal and is the price that will be financed.