California’s Energy Future: Electricity from Renewable Energy and Fossil Fuels with Carbon Capture and Sequestration

A report released by the California Council for Science and Technology examines pathways for achieving California’s aggressive greenhouse gas (GHG) reduction target of 80% below the 1990 level in 2050 through electricity generation from fossil fuel combustion with CO₂ capture and sequestration (“fossil/CCS”), or renewable energy technologies (wind, solar, geothermal, biomass, hydro, etc.).  The report is titled “California’s Energy Future: Electricity from Renewable Energy and Fossil Fuels with Carbon Capture and Sequestration.”

The report by Jane Long, co-chair of California’s Energy Futures Committee, Jeffery Greenblatt of the Environmental Energy Technologies Division at LBNL, and Bryan Hannegan of the Electric Power Research Institute, is a follow-up to the study "California's Energy Future— The View to 2050," published in May 2011. The analysis first estimated how emissions could be reduced through modifications to demand, including aggressive efficiency and electrification.

The authors developed two scenarios of electricity demand in the state through 2050. In the first, they assumed that maximum electricity demand that would result from business-as-usual plus economic and population growth without aggressive efficiency measures, but very high levels of electrification. In this case the total demand for electricity would be about 1,200 terawatt-hours/year (TWh/yr), with average generation of about 130 gigawatts (GW). In the second case, they used a much smaller estimate of demand that included aggressive, but realistic, amounts of both efficiency improvement and electrification in all energy sectors. The resulting demand for electricity is about 500 TWh/yr, with average generation of about 60 GW. By comparison, California’s electricity demand in 2005 was about 270 TWh/yr.

The report assumes there are three major ways to provide the rest of the electricity: nuclear power, fossil/CCS, and more renewable energy, and focuses on the latter two solutions. There is also a section exploring approaches for implementing load balancing without GHG emissions.

The report concludes that:

• Developing generation capacity is not a technical issue. Generation capacity to meet either the high or low level of demand could be developed with any of the three electricity supply choices.
• All of the electricity cases require load balancing to address peaking, ramping and intermittency of electricity supply resulting from the inherent variability of wind and solar resources. The use of natural gas for load balancing at the scales envisioned to be necessary in 2050 would produce significant amounts of GHG emissions. This problem is significantly larger for intermittent renewable energy.

 The California Council on Science and Technology is publishing a series of reports detailing the results of its Clean Energy Futures project exploring the remaining challenges—and possible solutions—to achieving California’s ambitious GHG target. This is the third follow-up to its initial Summary Report published last year. Additional reports will be released later this year.

Download the report “California’s Energy Future: Electricity from Renewable Energy and Fossil Fuels with Carbon Capture and Sequestration” from the California Council on Science and Technology website.