Comparison of Energy Sources and CO2 Emissions from Large California Utilities in 2015
We present a table of the energy sources of the large California utilities from their yearly Power Content Labels for 2015. These also include the overall California Power Content Label. The US results are for 2016. The numbers in the table are percentages. The different contributions to Renewables are not shown.
The Unspecified sources are out of state contributions that are not specifically contracted for. The large unspecified is the 41% for SCE or SC Edison. This is a result of the 2012 closure of the two San Onofre nuclear reactors because of engineering mistakes in replacing the heat exchangers. The Unspecified contributions are generally natural gas for the southern utilities, and hydro for northern utilities.
Last year we used our own relative scheme to compare the emissions in the last column. This year we present Emissions (Em) in standard units of pounds of CO2 per kiloWatt-hour. We take the US average of plant efficiencies giving Coal at 2.21 pounds of CO2 per kWh, and Natural Gas at 0.922 pounds of CO2 per kWh. The ratio of Natural Gas to Coal emissions per kWh is then 0.417. If all natural gas plants were upgraded to the most efficient combined cycle plants, this ratio could be as low as 0.34.
In the last column, for the northern utilities PG&E (Pacific Gas and Electric) and SMUD (Sacramento Municipal Utility District), we results, for Unspecified as being clean hydro. If instead they are efficient natural gas, PG&E becomes 0.39 pounds CO2/kWh, and SMUD becomes 0.65.
SFPUC is San Francisco Public Utilities Commission at no emissions. However, they get their hydro power and water from having dammed the Hetch Hetchy valley, which is another Yosemite type valley near Yosemite. This was certainly a major and continuing environmental loss for the state.
SV is the Silicon Valley utility.
Util | Coal | Gas | Ren | Nucl | Hydro | Unsp | Em |
US | 31 | 33 | 7 | 21 | 6 | 2 | 1.01 |
CA | 6 | 44 | 22 | 9 | 5 | 14 | 0.67 |
SCE | 0 | 26 | 25 | 6 | 2 | 41 | 0.62 |
PG&E | 0 | 25 | 30 | 23 | 6 | 17 | 0.23 |
LADWP | 21 | 25 | 21 | 10 | 3 | 4 | 0.73 |
SDG&E | 0 | 54 | 35 | 0 | 0 | 11 | 0.60 |
SMUD | 0 | 47 | 22 | 0 | 8 | 23 | 0.43 |
SFPUC | 0 | 0 | 6 | 0 | 94 | 0 | 0.00 |
SV | 9 | 46 | 27 | 0 | 13 | 3 | 0.45 |
LADWP is Los Angeles Department of Water and Power, which has out of state coal power contracts until 2024. The breakdown of CA 2015 renewables of 21.9% is 8.2% Wind, 6.0% Solar, 4.4% Geothermal, 2.6% Biomass & Biowaste, and 0.9% Eligible Hydroelectric.
CA 2015 clean energy total, summing Renewables, Hydro and Nuclear is 22% + 5% + 9% = 36% . California’s goal is to have 50% Renewables by 2030. So we are 22/50 = 44% there. If Nuclear and Hydro stayed the same, our total would be 50% + 9% + 5% = 64% clean power in 2030. The 6% of coal power would also be gone by then and replaced by clean power.