Page 149 - Alternative Energy Systems in Building Design

SOLAR POWER REBATE APPLICATION PROCEDURE 125

have established special design documentation submittal requirements that are manda-
tory for rebate qualification and approval.
In essence, initial rebate application forms require minimal design justification for
sizing the solar power cogeneration plant. Information on the application forms is
limited to the following:

■ Name and address of the owner and the solar power contractor
■ PV module manufacturer and model number (must be listed in CEC-approved
equipment)
■ PTC watts of the PV modules
■ Total number of PV modules
■ Total PV power output in PTC watts
■ The inverter manufacturer (must be listed in CEC-approved equipment)
■ Inverter model number and number of units (total output capacity)
■ Inverter efficiency in percent
■ The maximum site electrical demand load

On completion of the parameters, project incentive and cost calculations are calcu-
lated by the following formula:

Total eligible rebate watts (TERW) = total sum of PV PTC watts × inverter efficiency

Total rebate amount is calculated by multiplying the TERW by the rebate per watt
amount.
The following example is used to demonstrate the eligible rebate amounts that can
be expected from Southern California Gas Company.
Let’s assume that the a solar power platform provides an unshaded area for a quan-
tity of 530 SolarWorld model SW 175 monocrystalline modules, and a properly sized
inverter is selected from a manufacturer that has been listed under CEC-approved solar
power equipment. The rebate application calculation will be as follows:

■ PV module: SolarWorld Model SW 175 with dc rated output of 175 W
■ PV module PTC power output rating: 158.3 W
■ PV module area: 14 ft 2
■ Available unshaded platform space (approximately): 7500 ft 2
■ Total number of PV modules to be installed: 530 units
■ Total PTC output watts: 530 × 158.3 = 83,899 W
■ Inverter unit capacity chosen: 100 kW
■ Inverter efficiency: 94.5%
■ Total eligible rebate watts = 83,899 × 94.5% = 79,285 W
■ Adjusted incentive rebate per watt: $2.50
■ Total rebate eligibility: 79,285 × $2.50 = $198, 212.50

It should be noted that maximum allowable rentable solar energy is regulated and
capped by various rebate administrative agencies. For instance, Nevada Power caps