The U. S. and the Kingdom of Saudi Arabia have announced the intention to establish an international consortium to promote the research, development, and demonstration (RD&D) of supercritical carbon dioxide (sCO2) power cycles.

The announcement underscores the commitment by the U.S. and Saudi Arabia to increase government funding for clean energy technologies under the Mission Innovation Initiative unveiled during last year’s climate negotiations in Paris. Mission Innovation represents a landmark commitment by the U.S. and 19 other countries to double clean energy research and development (R&D) investment to tackle global climate change, provide affordable clean energy to consumers, and to create additional commercial opportunities in the clean energy economy.  

Power cycles based on a sCO2 working fluid have the potential for higher thermal efficiencies, lower capital costs and overall reduction in electricity cost compared to steam-based power cycles. These benefits present opportunities for the application of sCO2 power cycle technologies to numerous heat sources, including nuclear, concentrating solar, geothermal, waste heat recovery and fossil fuel power applications. For fossil fuel based applications these efficiency improvements can enable a power plant to generate the same amount of electricity from less fuel, thus decreasing CO2 emissions.

To date, the development of sCO2 power cycles has largely been limited to small-scale test loops and first-of-a-kind CO2-based systems up to 6 megawatt-electric (MWe) scale undergoing development testing for waste heat recovery applications. 

The current technology development risk for sCO2 power cycles is too high for independent private sector investment and requires initial government investment.

In March 2016, the Department of Energy (DOE) issued a funding opportunity announcement for a 10-MWe scale Supercritical Transformational Electric Power (STEP) facility that will evaluate the power cycle and component performance over a range of operating conditions.  Currently there are no  commercially-integrated sCO2 facilities that exists for higher temperature and high efficiency system testing, the 10 MWe STEP facility will serve as an opportunity for industry and government to work together to develop a first-of-its-kind technology at pilot-scale to facilitate commercialization of sCO2.

In Saudi Arabia, Saudi Aramco is working toward the development of many advanced power systems, including power cycles based on sCO2. These power cycles may reduce Saudi Arabia’s domestic energy consumption and help to reduce CO2 emissions. Saudi Aramco will continue to conduct extensive modeling and experimental works on various components of sCO2 power cycles with a goal to demonstrate this technology at relevant scale.

By sharing knowledge and best practices through the new international consortium, the collaboration between the U.S. and Saudi Arabia builds on the actions both nations are taking to advance sCO2 technologies to reduce the technical barriers and risks to commercialization of the sCO2 power cycle.  In addition to the U.S. and Saudi Arabia, other countries that are pursuing sCO2 R&D, including the Republic of Korea, will be invited to join the new consortium.