Comparison of CO2 Emissions from Large California Utilities in 2014


Even though all California Power Content Labels are not reported yet, it is useful to compare the latest ones for the United States, California, and the main California utility companies.  We also study the out-of-state power sources that make up a large part of the power mix, and their percentage CO2 emissions.

In order not to burden myself or the reader with complex and unfamiliar energy units for a relative comparison, we take the emissions of CO2 for an older natural gas plant at 34% efficiency as one unit of CO2 emissions.   Then an older coal plant at 34% efficiency has CO2 relative emissions at 1.78.  Emissions from nuclear, hydro, and renewables is taken as a relative 0.  Emissions from newer combined cycle natural gas plants at 55% efficiency would be taken as 0.6, but we have no separate accounting of these in the California Power Content Labels.  It’s time for them to catch up in this recent development.

The power type sources columns numbers are percentages of the utilities’ totals.  The final Total column   in the Total column is the unspecified part added in as if it were old natural gas plants as 1 times the fraction unspecified.  The data are for 2014.



Utility Coal Nat. Gas Ren. Nuc. Hydro Uns. Total
U. S. 39 27 7 19 6 0 .97
CA 6 45 20 9 6 15 .57+.15
SCE 0 27 24 6 3 40 .27+.40
PG&E 0 24 27 21 8 21 .24+.21
LADWP 40 22 20 9 2 7 .93+.07
SDG&E 0 48 32 0 0 20 .48+.20
SMUD 0 41 33 0 18 8 .41+.08
SFPUC 0 0 9 0 91 0 .00
Silicon Valley 11 42 36 0 15 -5 .63-.05
Anaheim 41  24  27  0  2  7  .97+.07



SCE is Southern California Edison; PG&E is Pacific Gas and Electric; LADWP is Los Angeles Department of Water and Power; SDG&E is San Diego Gas and Electric; SMUD is Sacramento Municipal Utilities District; SFPUC is San Francisco Public Utilities Commission using water and power from the Hetch Hetchy reservoir; and S. Valley is Silicon Valley.

It is clear that the US average is the most CO2 polluting, compared to California and the main California utilities.  LADWP is almost tied, and still importing coal power, although it is getting rid of those contracts as soon as possible.  San Francisco (SFPUC) is 100% clean, but the Sierra Club is still mad at it for damming the Hetch Hetchy valley, which is almost as beautiful as Yosemite Valley.   SC Edison is still adapting for losing 2.2 GigaWatts clean power in having to close the San Onofre nuclear reactors.  It has been drawing 1,700 GWh from each of the three Palo Verde reactors.  SCE has 40% of its power as Unspecified.  The next larger Unspecified is PG&E at 21%.  Unspecified power sources can be fairly clean, and being bought on the spot market save consumers money.

About Dennis SILVERMAN

I am a retired Professor of Physics and Astronomy at U C Irvine. For a decade I have been active in learning about energy and the environment, and in lecturing and attending classes at the Osher Lifelong Learning Institute (OLLI) at UC Irvine.
This entry was posted in California Power Mixes, Coal, Electric Power, Energy Efficiency, Fossil Fuel Energy, Greenhouse Gas Emissions, Hydropower, Natural Gas, Nuclear Energy, Renewable Energy, San Onofre, Solar Energy, Wind Energy. Bookmark the permalink.

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