Summary of Electric Utilities Emissions of Greenhouse Gases in Southern California
By Dennis Silverman, Dept. of Physics and Astronomy, UC Irvine.
This is a very brief talk for the Mayor’s Climate Protection Action Plan for Laguna Beach, but it applies to other parts of Southern California as well.
You don’t have to copy down these numbers, they are on my blog at: sites.uci.edu/energyobserver
CO2 emissions from SC Edison and San Diego Gas & Electric (SDG&E) are about equal. They are about 60% of the US average, and 90% of the California average. They are at 27% of a pure coal burning state.
California’s natural gas plants are now almost all highly efficient combined cycle plants, except for a segment of cogeneration plants, where extra heat is used to heat water, another green energy usage. The sum of California’s natural gas plants is only 42% as polluting, for a given amount of power, as coal would be.
California’s power is only 6% Coal, 44% Natural Gas, 22% Renewables, 9% Nuclear, 5% Hydro, and 14% Unspecified. That makes it 36% clean power.
Of the 22% Renewables: 8% is Wind, 6% is Solar, 4% is Geothermal, 3% is Biomass and Waste, and 1% is small Hydroelectric.
SCE has 41% undetermined power from out-of-state sources, which we are advised to consider as efficient natural gas plants. That is filling the deficit from the closure of the two, clean power, San Onofre nuclear reactors in 2012.
While California’s renewables are 22% now, the goal for 2020 is 33%, and for 2030 is 50%.
If we keep the 9% nuclear and 5% hydro, the present 36% clean power will be increased to 47% in 2020, and 64% in 2030.
SCE’s 25% renewables are broken down as: 9% Geothermal, 8% Wind, 7% Solar, and 1% biomass. Adding in clean Nuclear at 6% and Large Hydro at 2% gives SCE 33% Clean Power.
SDG&E’s 35% renewables are: 18% Solar, 15% Wind, and 2% Biomass. Without Nuclear and Hydro, SDG%E’s clean power is still 35%, comparable to SCE’s clean power at 33%.
I was also asked to compare resident’s power usage to that of visitors.
I took a standard visiting family as driving a 30 mile round trip, at 20 miles per gallon, considering fast and slow areas of driving. They then use 1.5 gallons of gas, giving 30 pounds of CO2 pollution. Local electricity generates about 0.6 pounds of CO2 per kWh. So their drive is equivalent to 50 kWh of pollution, or about two days’ worth for a typical household. However, since they come from inland regions, coming to the beach in the summer to escape the heat saves on their use of air conditioning. So their gas use is partly balanced out.
You can turn this around, and say that if a typical resident commutes 30 miles a day without carpooling, they are generating two days additional household pollution for each day commuting.
Finally, Laguna Beach residents are engaging in an enormous energy saving ecology, where in May Gray and June Gloom, only 65% of solar irradiance is warming the city, and this saves on air conditioning. The rest is largely reflected back into space, and is cooling the planet. This Marine Layer occurs on the west coasts of North America, South America, and Africa.