California’s electricity sector has seen many changes in the last 15 years from decoupling electricity consumption from utility revenues to implementation of a Renewables Portfolio Standard to a multi-sector greenhouse gas emissions reduction target of 1990 levels by 2020. How well are these policies contributing to the ultimate goal of greenhouse gas emissions reductions? Is the electricity sector doing its part to contribute to the emissions reductions needed?
The California Air Resources Board released the 2013 greenhouse gas emissions inventory on June 30, 2015, which showed that emissions fell by 1.5 million metric tons in 2013 compared to 2012 while the economy grew at 2.0 percent, a rate greater than the national average. Much of the reduction in greenhouse gas emissions can be attributed to the electricity sector. In fact, the electricity sector emissions inventory, both in-state and imports, fell a total of 5 million metric tons or 5 percent of total electricity emissions over 2012. In fact the total electricity sector is already about 20 percent below the emissions level of 1990. I think the success in decarbonizing the grid can definitely be attributable to the changes in the electricity sector. These policies have enabled the increase in energy efficiency measures, driven renewable procurement and reduced the reliance on coal power.
It typically takes some period of time before markets catch up to new policies, and despite the negative prognostications of doubters, the markets have responded resoundingly. The following table shows renewable generation from 1983 to 2013.
There are two periods where generation increases are clearly visible. During the period of the 1980s when projects came online as a result of standard contracts and then roughly after 2008, when projects procured under the Renewables Portfolio Standard came online. The sharp increase in renewable energy generation after 2008 correlates well with a sharp decrease in greenhouse gas emissions reductions in the electricity sector.
From 2008 to 2013, renewable generation almost doubled, coal generation reduced by more than half, and greenhouse gas emissions reduced by a quarter.*
*Note: Total System Power should not be used to estimate compliance with the Renewable Portfolio Standard. There are far too many intricacies to the Renewable Portfolio Standard like procurement compliance buckets, historic carry-over rules, calculation of renewable generation over retail sales, etc.