We have developed a roadmap of CO2 utilization technologies for the California Energy Commission, a state government energy research, policy and permitting agency. The objective of the roadmap is to identify technologies that can make significant contributions to the state's 2020 and 2050 greenhouse gas (CHG) reduction goals. The state of California, under Assembly Bill 32, is committed to achieving reductions to 1990 GHG inventory levels by 2020 and, under Governor's Executive Order S-3-05, to 80 percent below those levels by 2050. The roadmap will guide future R&D investment and policy development for enabling carbon utilization technologies in California.
For the purposes of the roadmap, we defined utilization as including technologies that produce a useful product from anthropogenic CO2, or through the processes of capture or sequestration of CO2. Technologies may contribute to reductions directly by permanently sequestering CO2, or indirectly by displacing the use of fossil fuels or more potent GHGs, such as CFCs. Technologies considered include: CO2 as a working fluid (including enhanced oil recovery (EOR), enhanced gas recovery (EGR), and enhanced geothermal systems (EGS)), chemical feedstocks, biofuels, building materials, compressed gas energy storage, cushion gas for natural gas storage, and water and marketable minerals produced from displaced sequestration reservoir fluids.
Evaluation criteria include technological maturity, potential market size, purity of CO2 required, commercialization time frame, environmental impacts, water use, data on energy-carbon life cycle analysis, and potential local economic benefits such as job creation. In addition, we evaluated the potential impact of non-technical barriers to commercial- scale adoption, such as the need for clear accounting protocols to provide incentives for CO2 producers to adopt these technologies to meet carbon standards.
It may be possible to integrate different utilization approaches. For example, CO2 can be reduced to produce methanol or formic acid, which can be converted into fuels. Other processes to functionalize the carbon atom produce saleable chemicals, such as urea. By combining these two approaches, synthesis of even more chemicals directly from CO2 could be achieved.
Widespread deployment of CO2 utilization technologies also depends on integration into planning of a future carbon- energy infrastructure. While single projects for some technologies, such as EOR, may create a demand comparable to the CO2 volumes generated by large sources, other technologies may have to be aggregated and/or combined with geologic sequestration to provide the volume of sequestration required. Deployment networks provide opportunities for cost optimization of pipeline infrastructure and for focusing public or private investment to facilitate commercialization.
Currently in California, utilization projects are in the research, pilot, or permitting stages, including projects to combine urea production and EOR, produce high carbon-content building materials, and develop chemical and biological CO2 recycling technologies. None of these projects have yet reached the development stage necessary to demonstrate whether the technologies can contribute effectively to reducing California's CHG emissions.