RSS FeedsEnergy Resources
Electricity
Natural Gas
Gasoline
The purpose of the energy resources chapter of the Baseline Data Report is to discuss historical, existing, and projected electricity and natural gas production, consumption, and peak demand in the County. Gasoline consumption by vehicles in the County is also discussed.
 Countywide Natural Gas Consumption (2003) by sector |
In this chapter, the County is assessed as a single region rather than divided into evaluation areas due to data limitations. The primary sources for information in this energy chapter are Pacific Gas and Electric Company (PG&E) and the California Energy Commission (CEC). The CEC provided GIS maps of major electrical transmission lines and natural gas pipelines in the County as well as estimates of electricity and natural gas consumption rates for the entire County for the years 1990–2003. PG&E provided estimates of transmission capacity and system upgrades. Vehicular energy consumption is based on Caltrans’ California Motor Vehicle Stock, Travel, and Fuel Forecast reports, which project vehicle fuel consumption in gallons (Caltrans 2004). Vehicular fuel consumption estimates utilize longterm projections of statewide population, economic growth (total personal income), fuel prices, inflation, and interest rates to estimate gallons of gasoline and diesel consumed per County.
ELECTRICITY
In the County, PG&E is the main energy utility provider for all sectors of the community. There are six energy-producing facilities in the County, providing a total capacity of 20.06 megawatts (MW). This was sufficient to supply approximately 8.5% of the County’s peak electrical demand for 2004. Small-scale, private energy generation by solar, wind, and biogas is also on the rise throughout the County, particularly in association with wineries.
Total electricity consumption in 2003 in Napa County was 512.5 thousand barrel of oil equivalents (BOEs), compared to 365 thousand BOEs in 1990 (i.e., 40% greater in 2003). Per capita use increased at a much slower rate during the same time period (1.2% per year on the average), to 2.89 BOEs in 2003. However, total energy consumption peaked in 2000 at 540.8 BOEs. This peak, and subsequent decline, is attributed to fluctuations in the mining and commercial sectors. In 1990, electricity consumption by mining operations accounted for 0.5% of the total energy delivered to the County. Seven years later, in 1997, mining accounted for over 9% of total consumption in the County. This fluctuation represents an increase of over 2,400%. Increases in the consumption by the mining industry, combined with a consumption peak within the commercial industry, led to an overall energy consumption peak in 2000.
Napa County Per Capita and Total Electricity Consumption
|
Year
|
Per Capita Electricity Consumption | Total Electricity Consumption |
|
1990
|
3.30 BOE | 365.4 thousand BOE |
|
2000
|
4.35 BOE | 540.8 thousand BOE |
|
2003
|
3.89 BOE | 512.5 thousand BOE |
The residential sector is by far the largest consumer of natural gas in the County, accounting for 44% of the Countywide annual consumption in 2003. The commercial sector is the second largest consumer of electricity, accounting for 32% of consumption in that same year. The industrial sector was a distant third, accounting for 16%. The remaining sectors—transportation, communication and utilities [TCU]; mining; and agriculture—each accounted for less than 8% of the total electricity consumed. Trends in peak electricity demand in the County are similar to those discussed for total annual energy consumption. Peak demand over the 13-year period has increased 38% (approximately 2.5% per year on average) to 105.1 BOE in 2003. Per capita peak demand, on the other hand, has actually decreased 16% overall or 1.1% per year on average. There are three major electrical transmission routes that cross from east to west through the County, and nine electrical substations in the County, all owned by PG&E.
NATURAL GAS
There are no natural gas production wells in Napa County (CEC 2004).
Between 1990 and 2003, annual energy consumption as natural gas has been consistently higher than annual energy consumption as electricity, but the difference has been steadily decreasing. While electricity demand has grown, natural gas demand has remained relatively constant. In 2003, total natural gas use was at 663 thousand BOEs, compared to 669 thousand BOEs in 1990. Per capita natural gas use has actually dropped 1.4% per year on the average over this period to 5.04 BOEs in 2003.
Napa County Per Capita and Total Natural Gas Consumption
|
Year
|
Per Capita Natural Gas Consumption | Total Natural Gas Consumption |
|
1990
|
6.04 BOE | 668.79 thousand BOE |
|
2000
|
5.57 BOE | 691.77 thousand BOE |
|
2003
|
4.04 BOE | 663.65 thousand BOE |
The residential sector is by far the largest consumer of natural gas in the County, accounting for 58% of the countywide annual consumption in 2003. The commercial sector is the second largest consumer of natural gas, accounting for 28% of consumption in that same year. The industrial sector accounted for 13%, and the TCU, mining, and agriculture sectors combined accounted for less than 1% of the total natural gas consumption in 2003.
PG&E designs gas facilities to ensure reliable gas service to core customers on an “abnormal peak day” (APD). The expected APD gas daily demand for Napa County in 2004 was 36,890 thousand square feet (mcf) (378,860.3 therms). The current transmission capacity is above this peak demand.
PG&E predicts that there will be no gas transmission capacity constraints in Napa County within the next 5 years. Currently, PG&E reviews capacity in 5-year periods; however, it plans to begin projecting transmission demand for 10-year periods. The manager of Transmission System Planning (PG&E) believes that current transmission capacity may last past the project 5-year period. The last gas transmission upgrade in Napa County was performed in 2004 in the St. Helena/Calistoga/Angwin area. No upgrades are planned to the Napa County gas transmission system in the next 5 years.
GASOLINE
Between 1993 and 2003, annual gasoline consumption in Napa County increased nearly 27%, or 2.4% per year, to 61.935 million gallons in 2003. Per capita use also increased but by a smaller amount (just under 11%). This is expected because a portion of the increase in overall use appears to be related to increased tourist travel in the Napa Valley. This conclusion is supported by the fact that the average annual per capita gasoline consumption for Napa County in 2003 (470.09 gallons per capita) is 9.3% (almost 44 gallons) higher than the average for California as a whole.
