(41e) Formation of Synthetic Fuels Using Solar Concentrator Photovoltics (SCPV) and High Temperature Co-Electrolysis of CO2 and H2O

Carbon dioxide is considered a greenhouse gas (GHG) that reflects solar radiation and consequently increases the temperature of the earth. Many countries are now considering putting a tax on CO2 emissions that will increase the cost of products that are associated with those emissions. The most common method currently considered for dealing with CO2 emissions is the capture of the gas, pressurization, and then sequestration in either rock formations or saline aquifers. This is relatively costly in both capital investment and operation of the equipment. Also, there is the possibility that this CO2 will escape at some point in the future subjecting the company in question to an uncertain risk.

Ceramatec has been investigating an alternative approach that converts the CO2 into a useful product that can then be sold. Using the solid oxide fuel cell materials set in conjunction with a non-carbon source of energy it is possible to generate synthesis gas (CO and H2) and oxygen from CO2 and H2O. SCPV systems are the most efficient generators of solar electricity and generate high quality heat at the same time. HTCE uses both the solar electricity and the heat to electrolyze the CO2 and H2O at double the efficiency of traditional electrolysis. Once the synthesis gas is generated it is possible to utilize either a methanation reaction to generate synthetic natural gas or to pressurize the synthesis gas to feed a Fischer Tropsch reaction to produce liquid fuels. Ceramatec has accomplished both of these reactions in a laboratory environment.

This paper will discuss this alternative approach to the disposal of CO2. This approach has the following advantages: permanent disposal, usable product, storage of solar energy in fuel, reduction of GHG, reduction in solar radiation, and no additional GHG. The paper will discuss the application of the technologies, results of tests conducted to date, and the economics of the technology versus alternative approaches. It will also show the results of converting the synthesis gas to both synthetic natural gas and Fischer Tropsch liquid fuels.