SGIP Program Impacts

Delivered Energy

During 2008, SGIP projects delivered over 718,000 MWh of electricity to California’s grid.

Thermal cogeneration systems (fuel cells, engines, and turbines) provided over 63% of the electricity. Photovoltaic projects were the second largest supplier at 27%.

PG&E was again the largest utility contributor, providing over 40% of the total energy delivered.

Peak Demand

Total SGIP project capacity coincident with the 2008 CAISO peak was over 141 MW representing an aggregate peak hour impact of 0.44 kWh per kW of rebated capacity. 

Of the eligible technologies, gas turbines showed the highest peak capacity factor of 0.84 kWh of peak capacity per kWh of rebated capacity, followed by PV at 0.59 kWh per kW.

Transmission and Distribution System

PV technologies showed afternoon peak reduction factors for PV ranging from 42 percent to 63 percent.

These factors equate to the kW of peak reduction per kW of rebated PV. 

The absolute peak loading reduction was found to be small due to the low penetration of SGIP technologies. However, increased SGIP installations and the inclusion of advanced energy storage systems should both increase the benefits of SGIP.

Greenhouse Gas (GHG) Emissions

SGIP technologies can have a significant potential impact on GHG emission reductions by:

1. Displacement of grid based electricity from natural gas fueled central power plants (i.e., by renewable DG technologies that do not burn natural gas such as PV and wind);
2. Displacement of natural gas that would have been burned in boilers to provide on-site heating or cooling; and
3. Capture and use of methane via biogas powered DG facilities.

In 2008, SGIP provided net GHG emission reductions of over 175,000 tons of CO2 equivalent gases; bringing the cumulative reduction in the past four program years alone to 498,000 tons of CO2 equivalent gases. This is equivalent to reducing oil consumption by over one million barrels!

In 2008, PV provided approximately 65% of these reductions, followed by biogas-fueled facilities which reduced an additional 60,000 tons of CO2 equivalent GHGs.

PG&E was the largest contributor of emissions reductions with 59% of the total.

Overall, the SGIP provided net GHG emission reductions of over 175,000 tons of CO2 equivalent in 2008.

PV provided the greatest net reduction at over 115,000 tons of CO2 equivalent gases.

Biogas-fueled DG facilities provided the next largest GHG reduction at over 60,000 tons of CO2 equivalent.