One of many approaches to combating climate change is “Carbon Capture and Geologic Sequestration” (CCS). It’s a pretty straightforward idea: capture climate-change-causing carbon emissions and lock them up underground, rather than letting them float up into the atmosphere where they would contribute to global warming.
The concept may be simple, but the actual engineering of it is as complicated as you might guess. The first problem is capturing and transporting CO2 emissions to their “resting place.” And then comes the second, injecting the CO2 into a deep geologic formations that will trap it underground for hundreds to thousands of years. Suitable homes for such captured CO2 include oil and gas fields (they’re already drilling deep down anyway), saline aquifers, and deep coal seams.
As it happens, several CCS projects are underway in Norway, Algeria, and Canada and more are planned in the United States, China, Australia, and other European countries. In fact, four CCS projects are currently active, each injecting roughly 1 million metric tonnes of CO2 per year. Two projects involve injecting CO2 far below the seafloor into deep gas formations – the Sleipner natural gas field in the North Sea, about 250 kilometers off the coast of Norway; and the Snøhvit natural gas field in the Barents Sea. A third project in In Salah, Algeria, involves injecting captured CO2 into a land-locked deep gas formation. Finally, the Weyburn-Midale CO2 project in Saskatchewan, Canada, involves injecting CO2 into depleted oil fields in order to increase reservoir pressure and oil fluidity – the better to extract additional oil from the fields, while trapping the CO2 underground.
In order for CCS to be implemented as a major climate change mitigation technology, however, projects will need to move to the large-scale commercial stage and inject and sequester billions, not millions, of tonnes of CO2 each year. Experts estimate such technology could be ready on a commercial scale by 2015 and in widespread use by 2020 (other estimates say 2030). And that’ll cost a lot of money. The U.S. Department of Energy has funded a number of regional carbon sequestration partnerships aimed at developing the technology and implementing it in several large-scale pilot projects. President Obama’s stimulus bill provided an additional $3.4 billion for CCS demonstration projects, bringing the entire federal investment to more than $8 billion.
That kind of funding, together with economic incentives and regulatory requirements (including an adequate price on CO2 emissions) will be needed to induce industry to begin building “carbon-capture ready” plants than can be used to support capture and sequestration technology when it comes on line. New plants are necessary because adding CO2 capture capability cannot be done feasibly or effectively as an “end-of-pipe” modification.
CCS has some detractors in the environmental community. Greenpeace International, to focus on one, released a report in May 2008 entitled “False Hope,” in which it contends that CCS wastes energy, creates unacceptable risks of leakage, is too expensive, undermines funding for more sustainable solutions to potential climate change, carries significant liability risks, and cannot be implemented in time to avoid dangerous climate change. Other environmental groups, however, such as Environmental Defense Fund, Natural Resources Defense Council, World Resources Institute, and the Nature Conservancy, see CCS as a necessary technology to help mitigate the effects of climate change.
The technology has its risks, to be sure. First, relying on CCS would almost certainly mean prolonging the use of coal as a source of electricity – and that raises a host of environmental issues, including the adverse effects from mountaintop removal of coal, acid mine drainage, land subsidence, air pollution, and acid rain. Second, we may not be as good at sequestering emissions as we think, and undetected leaks could lead to dangerously high concentrations of CO2 escaping from their underground chambers.
The critical requirement in going forward with CCS therefore will be to ensure that appropriate regulation, legal remedies, and funding mechanisms are put in place, to ensure that CCS is developed in a manner that minimizes the risk of harm to human health, the environment, and the climate. For instance, some in industry and government have argued that the federal government or states should accept ownership of sequestered CO2 and indemnify CCS operators for any associated harm. That approach would eliminate industry incentives to engage in good site selection and responsible risk management throughout the lifetime of CCS projects. A better approach is to use existing tort and environmental statutory liability to the extent they apply, but at the same time develop a comprehensive federal regulatory program governing CCS and then place on top of it a funding system consisting of industry-financed insurance, bonding, selected damage caps (for early pilot projects only), and pooled federal funding that would provide protection for both CCS operators and those potentially harmed by CCS. Such a system can go a long way in decreasing the risks of climate change while managing the risks of CCS.
As one environmental organization representative put it, CCS “is a terrible idea that we desperately need.” That’s just about right. As it happens, CCS is an important component of the House-passed Waxman-Markey bill, which allocates funds for developing sequestration technology, requires new coal plants to be CCS-friendly, and requires the EPA Administrator to develop a strategy for overcoming the commercial barriers to CCS. The problems with CCS notwithstanding, the plain truth is that we’re going to need every bit of carbon emissions savings we can accomplish.