While many say a large scale transition from burning fossil fuels to renewable energy sources is the ideal approach to achieving climate neutrality, scientists and engineers are exploring the possibility of carbon capture and storage as a temporary solution.

CCS technology is targeted towards fossil-fuel burning power plants, which make the most significant contribution to human CO2 emissions. The concept involves three basic steps: capture, transport and storage. First, engineers trap the CO2, separating it from other waste gases at the power plant and compressing into a liquid state. They then pump it through a pipeline underground or deep into the ocean, where it is no longer directly exposed to the atmosphere.

Prof. Andrew Hunter, chemical engineering, teaches ChemE 6650: Energy Engineering. For the past few years, his class project involved calculating the cost of capturing CO2 from the Cornell power plant. According to Hunter, “It is possible to sequester carbon dioxide, but the technology of extracting it from waste gas coming out of the power plant is not well developed.”

A sequestration system capable of removing 250,000 tons of CO2 per year costs $50-60 million, and it would require up to 20 percent of the power plant’s current capacity. Despite the cost, policy makers may soon force companies to meet emission performance standards, which would require the implementation of CCS technology.

But burying vast quantities of CO2 will require more than a nice patch of dirt and a shovel. Volume, safety and environmental effects are taken into consideration when scoping out potential storage sites.

Prof. Terry Jordan, earth and atmospheric sciences, leads a team that studies underground carbon storage capability in New York State. Companies that drill oil wells in New York are required to send their geologic data to the New York State Museum, where it is compiled into a database. Jordan’s team examines this archived data to determine the approximate amount of CO2 that could be pumped underground.

They focus on sedimentary rock regions at least 3,000 feet deep, where CO2 will remain in a fluid-like state. These areas could include old oil and natural gas reservoirs, or, as in much of central New York, formations that are naturally filled with saline water. The sites must be porous enough to absorb a significant amount of CO2, and be covered by a layer of impermeable rock which would act as a CO2 seal.

According to Jordan, “The intent of a study like ours is to provide the state with sufficient information to determine new policies for carbon sequestration. This information could also be used by electrical power companies to begin thinking strategically about the future of this technology.”

John Tombari ’81, a former mechanical engineering student and president of Schlumberger Carbon Services, hopes to commercialize the carbon sequestration process. According to Tombari, geological storage safety is the greatest cause for concern. His company performs detailed risk analyses of underground storage sites — saline formations in particular — and investigates the possibility of long-term leakage.

Another prospective storage location is deep in the ocean, but little is known about the long-term effects on marine life and the risk of leakage. In 1986, an eruption of natural carbon dioxide in Lake Nyos, Cameroon resulted in the asphyxiation of almost 2,000 people, demonstrating the potentially disastrous effects of ocean storage. Further research will be required to determine the environmental consequences of this option.

While proponents of CCS technology emphasize the continued importance of conservation, carbon capture and storage may be a feasible method to reduce CO2 emissions at a large scale in a short amount of time. In conjunction with the search for clean energy sources and green urban planning, entrepreneurs like Tombari believe CCS technology could become a key step towards a climate-friendly future.