Water Related Electricity Demand in California A Report By Lon W. House, Ph.D May 7, 2007

Genesis of Report California Energy Commission (CEC) Integrated Energy policy Report 2005 (IEPR 2005) –roughly 20 percent of the state's electricity consumption, one-third of non-power plant natural gas consumption, and about 88 million gallons of diesel fuel consumption A collaborative process involving the IOUs, the CEC, and the water agencies.

Purpose of Analysis Determine on-peak water related electrical demands in state Profile of water deliveries by customer class Embedded peak electrical demand of water

Methodology

Customer Class Water Deliveries Ag separate industrial classification Residential

California Residential Summer Peak Day Water Deliveries 400, a.m., 334,000,000 gallons at 8 p.m..

California Water Related Peak Day Electrical Demand

Utility Service Area Characteristics

Uses of This Information Statewide, and for each utility, embedded peak electrical demand for water Statewide, and for each utility, a peak day customer class water electric demand profile

Embedded Energy Determination For each IOU we have: 1) fresh, wastewater, and agricultural hourly electricity demand (MW), 2)water consumption profiles by hour (mgal). Embedded energy for each IOU is simply the sum of the electrical use divided by the sum of the water use (although you can get it by hour if you want).

Average for each IOU as determined on previous slide. For PG&E high is Cal-Am values from Green Buildings Report with a correction to include all the wateswater treated, low is East Bay values from Green Buildings Report. For SCE and SDG&E, high is the same ratio as Cal-Am is to PG&E average, low is same ratio as East Bay is to PG&E average.

GHG Determination Average wastewater emissions taken from CEC inventory report (Table A- 4, CEC SF, December 2006) Ca utility average GHG emissions levels taken from EIA Updated State-Level Greenhouse Gas Emission Coefficients for Electricity Generation, April SAR CO2 equivalents of 21 for methane and 310 for N20 used (CEC report) Total GHG savings = kwh reduced * CO2+CH4eq+N2Oeq/kWh plus wastewater mgal reduced * CO2+CH4eq+N2Oeq/mgal

1 Minute Version IOUs provided recorded hourly electricity sales by standard industrial classification for 2005 summer peak day –used fresh water, sewage (wastewater), and agricultural pumping –cross checked against QFER filings and CEC adopted IEPR demand forecast for 2005 Water use was taken from DWR Bulletin (State Water Plan) Residential water use was determined using standard industry profiles adjusted for recorded California indoor and outdoor water use. –Ag water separate, total urban water - residential water = commercial/industrial water Embedded energy determined by dividing total IOU water related kWh by mgal provided.