Exploring the effectiveness of reducing the net cost of carbon capture and storage from fossil fuel sources, the most egregious of which is pulverized coal-fired power plants, but also natural gas combined cycle power plants.

The Challenge

More than a third of the electricity generated in the State of Texas comes from coal. Every year, each coal-fired power plants release millions of tons of carbon dioxide (CO2) into our atmosphere, prompting efforts to reduce these so-called greenhouse emissions and help curb global warming. Much of this work has centered on developing technology to capture and store CO2. The problem is that current approaches to carbon capture and sequestration (CCS) are not economically viable without significant subsidies, or a very high price on carbon.

In fact, technology in place today requires roughly one-third of a typical coal-fired power plant’s energy be dedicated to CO2 capture and pressurization – a cost that renders such methods uneconomical. Independent of CCS research, technology has advanced in the production of energy from geothermal aquifers, but the two technologies have never been paired to help solve this problem. Until now.

The Energy Institute Solution

A team of scientists led by University of Texas at Austin Professor Gary Pope has developed a new, game-changing idea that combines these two technologies and adds another – the dissolution of CO2 into extracted brine, which is then re-injected back into the aquifer. This alternative approach to CO2 injection takes advantage of both dissolved methane and heat content in geo-pressured geothermal saline aquifers. Conservative calculations indicate this alternative method could reduce the cost of CCS such that it could compete in a market environment without subsidies or a price on carbon.

The University team, in partnership with the Lower Colorado River Authority and NRG Energy, submitted a proposal for an engineering study that would examine the economics of this new approach, but the Department of Energy chose not to fund the request. The Energy Institute is now pursuing funding from other sources interested in preserving the role of coal in electricity production with technology that cost-effectively reduces CO2 emissions.

Video: Learn about Carbon Capture and Sequestration