Comparisons of California Utilities’ Power Sources and Emissions
We compare the Power Content Labels of leading California utilities for 2016 as to their sources. We also estimate their mean emissions as pounds of CO2 per kiloWatt hour (kWh) of electrical energy.
California has almost completely highly efficient combined cycle or cogeneration natural gas power plants. We take the emissions of the combined cycle natural gas plants as 0.922 lbs CO2/kWh. We take the coal plants as older inefficient plant’s emissions at 2.21 lbs CO2/kWh.
The columns in the table are for Utility, Coal, Natural Gas, Renewables, Nuclear, Large Hydro, Unspecified, and Emissions. Unspecified are out-of-state power mixes which are not directly contracted for. For Northern California we take the out-of-state sources as clean Large Hydro, and for Southern California, as Efficient Natural Gas, as advised by the California power content label advisors.
| Util | Coal | Gas | Ren | Nucl | Hydro | Unsp | Em |
| US | 30.4 | 33.8 | 8.4 | 19.7 | 6.5 | 0.7 | 0.98 |
| CA | 4 | 37 | 25 | 9 | 10 | 15 | .43-.57 |
| SCE | 0 | 19 | 28 | 6 | 6 | 41 | .55 |
| PG&E | 0 | 17 | 33 | 24 | 12 | 14 | .16 |
| LADWP | 19 | 34 | 29 | 9 | 3 | 6 | .79 |
| SDG&E | 0 | 42 | 43 | 0 | 0 | 15 | .53 |
| SMUD | 0 | 41 | 20 | 0 | 23 | 16 | .38 |
| SFPUC | 0 | 0 | 1 | 0 | 99 | 0 | 0 |
| SV | 10 | 35 | 28 | 0 | 24 | 4 | .59 |
There is a range for California emissions, 0.43-0.57 lbs. CO2 per kWh , depending if the unspecified is pure hydro to pure natural gas.
Almost all of these utilities have decreased their emissions from my 2015 analysis, except for LADWP, which is up at 0.79 from 0.73, and SV, up at 0.59 from 0.45. SV is Silicon Valley, which I include just to check up on the SV digital industries.
As usual, the San Francisco Public Utility Commission, which draws almost all of its power as large hydro from the Hetch Hetchy reservoir and dam, is totally clean power.
The California utility with the largest emissions is Los Angeles at 19% Coal usage, which cannot get rid of those contracts until 2024. That is a lot of power to replace with renewables, unless they are planned well ahead of time. On the other hand, new solar cells are 50% more efficient now and cheaper, and may still improve by 2024.
After LADWP, the most emissions are from SV at 0.59 and SCE at 0.55. We compare SCE to the US average, and find that it is down to 56% of the US average, quite a remarkable achievement. This is even more of an achievement since the two San Onofre nuclear reactors closed down. SCE will, we hope, build more renewables and compensating natural gas in the state, and cut down their Unspecified 41%, or contract and account for it.
