The Carbon Value of San Onofre to the California Grid is Minimal. [View all]

[kristopher]

There have been a steady stream of overtly false claims related to the carbon costs of San Onofre's closing. Here is a comprehensive explanation of what is going on from the NRDC.

The next time you read one of the false claims by nuclear industry shills about importing coal fired electricity or replacing SO watt for watt with natural gas, just remember that the information from the NRDC isn't secret. If these so-call analysts wanted to be truthful, it would be no more difficult to find accurate information than it was for them to produce the lies they're putting out.

Without SONGS, California still has more than enough capacity to meet their needs:

In order to keep the lights on, the ISO needs to have more generation available than consumers are expected to use. This is known as a “reserve margin,” and the California Public Utilities Commission requires the utilities to plan for a 15% cushion. And the state already has more power plants than we need to pass that test. This summer, the ISO expects to easily exceed that margin under normal conditions, and to still avoid rolling blackouts even under extreme conditions (like if a lot of power plants go down unexpectedly at the same time customers’ demand is unusually high).




Source: ISO (Note: SP 26 and NP 26 are roughly Southern and Northern California, respectively)

As you can see the problem presented by the shutdown isn't having enough capacity to meet demand.

So why, in 2012 when SO shut down, did they need to pull 2 retired natgas generators (450MW) out of retirement in nearby Huntington Beach?

Blame it on a grid designed around centralized generation. The gaping hole in the system left by the shutdown of a large centralized source of generation causes a lot of problems besides the loss of ability to meet demand.

...the grid needs the “voltage support” SONGS used to provide.

Since a major part of the Southern California electric grid was built around SONGS, it is a lot harder for the transmission grid to remain stable without the plant operating and providing that voltage support. This all gets very technical fast, but the important thing to know is that there are different ways to provide voltage support (and they don’t all require burning fossil fuels at a power plant). So even though one might expect the state to fill the hole left by SONGS with more dirty power plants, this year the state is taking a better and cleaner approach.

So what happens now?

...(Huntington Beach - k) is instead being converted into “synchronous condensers,” which provide voltage support without onsite emissions. (The synchronous condensers operate like electric motors and use a small amount of energy from the grid in the process.) Other emissions-free efforts to fill the hole left by SONGS include installation of capacitors and upgrades to a local transmission line so that if the line has a problem, only part of it goes down instead of the whole thing.

<snip>

The Public Utilities Commission should continue to build on the great start made this year by requiring utilities to fill the gap with efficient and clean resources by:

making the electric grid more resilient through transmission system upgrades;
adding renewable resources in different geographic regions to take advantage of the different times when they’re available; and
avoiding new generation through more aggressive efforts to help customers:
improve the efficiency of their homes and businesses;
reduce consumption during costly “peak” periods; and
use clean on-site generation like solar panels.

Information courtesy of the wonderful folks at the Natural Resources Defense Council.
http://switchboard.nrdc.org/blogs/dwang/replacing_songs.html


ETA:
With the large scale "hole" in the grid created by the unexpected shutdown of SO, the general basics of California's grid are worth looking at again.

While the local nuclear acolytes will automatically say coal is going to be the main replacement, that is highly unlikely. The same goes for the insane predictions that natural gas will replace it. Due to a 2006 law forbidding municipal and investor owned utilities from signing new contracts for out of state coal, California's energy mix is only 8% coal (3% in state 5% imported) and that number is set to decline as LA has passed a law to phase out coal completely by 2025 (they currently get 44% of their power from coal). And while the mix is 35% natural gas, the state mandates at least 33% renewables by 2020 and they still need significant capacity to meet that goal.

The worst aspect will be some natural gas, but the RPS mandate of 33% renewables will weigh heavily in investment decision-making.

This is shows the trends fairly well:

Total System Power for 2011: Changes from 2010
In 2011, Total System Power for California was marginally higher by half of a percent from 2010. The two primary reasons are the ongoing recession and continued mild temperatures. The effects of the recession resulted in a peak demand that was 5 percent less than the forecast. As for temperatures, they were lower than normal during the spring, near normal temperatures during the summer, and above normal temperatures during both the fall and winter.1 By design, California's electric generation system delivers electricity quickly to match peak air conditioning load conditions in the summer.

In-state generation declined by 2.4 percent in 2011 however net imports from the Northwest and Southwest combined made up for the difference. In particular, energy imports from the Northwest in 2011 increased by 42.7 percent due primarily to an increase in hydroelectric generation resulting from higher precipitation in the Northwest. Between March and May 2011, Oregon and Washington experienced their wettest periods in the last 116 and 117 years respectively.2

With the conversion of Mt. Poso Cogeneration coal facility to a biomass plant complete, the in-state coal category showed a slight decline from 2010. Mt. Poso Cogeneration is about 10 miles north of Bakersfield.

Large hydroelectric generation, a category based on nameplate capacity of 30 megawatts (MW) and larger, showed a significant increase of 24.8% for in-state generation. This coincides with California experiencing one of its wettest years. After three relatively dry years, statewide precipitation during the 2010 Water Year (ending September 30, 2010) was 105% of average. Precipitation during the 2011 Water Year (ending September 30, 2011) was 135% of average, and runoff was 146% of average. Though January 2011 was remarkably dry, the months of March and May were extremely wet with peak snowmelt in early July. As a result, in-state hydroelectric generation in 2011 was 127% of average compared to 101% in 2010.

Generally, when snowmelt and runoff is plentiful, California's hydroelectricity is less expensive to purchase than electricity generated by plants using natural gas-fired generation. Therefore, usage of natural gas-fired generation is reduced ("displaced&quot . This is especially so during the spring and fall months and during off-peak summer hours (afternoon and early evening hours). Wind generation increased in 2011 reflecting the continued siting of new wind projects in the state. Solar also saw some increase as commercial-scale systems came online in 2011.

Reporting requirements for Total System Power are limited to projects rated at 1MW and larger. Because most solar photovoltaic (PV) systems on residential households and businesses are less than 1 MW, data on them is not collected. As more installations of solar PV and other "behind the meter" distributed generation technologies take place, consumption of power delivered by utilities will continue to decrease. Whether to exclude these smaller systems from the Total System Power summary may need addressing in future, if the aggregate capacity and energy of such small systems becomes a significant portion of the state's generation mixture.

1 http://www.ncdc.noaa.gov/sotc/national/2011/13
2 http://www.ncdc.noaa.gov/sotc/national/2011/13

More at http://energyalmanac.ca.gov/electricity/total_system_power.html

See also
Los Angeles Bans Coal Power
Coal Free by 2025

By Jon Carter
Friday, March 22nd, 2013
http://www.energyandcapital.com/articles/los-angeles-bans-coal-power/3209