July 15, 2008

New strategies for conquering environmental challenges

Angela Neville, JD

A closer look at carbon capture and sequestration

In his presentation about carbon capture and sequestration (CCS), speaker Steven M. Carpenter, director F&C business at Marshall Miller & Associates, provided a candid assessment of many of the pros and cons related to this new approach to dealing with CO₂.

“Technology exists to capture up to 90% of CO₂ emissions at electrical power plants. The capture systems include liquid amine absorption, oxygen-fired combustion, and precombustion gasification,” Carpenter said. “Cost is the main issues, especially to retrofit existing facilities.”

He also pointed out the challenges associated with different types of carbon transport. Pipeline transport from the source to the sink can involve legal and regulatory issues and energy consumption to compress CO₂. In contrast, rail transport of carbon from source to sink is more expensive, requires liquefying and regasifying the CO₂, and adds the expense of energy consumed to liquefy CO₂ and move it by rail. Truck transport of carbon is the most expensive and least energy efficient.

Other CCS hurdles are related to legal and regulatory issues. According to Carpenter, these include:

• Issues related to whether the state department of transportation or federal preemption controls source-to-sink transportation.
• Ownership issues pertaining to storage reservoirs, sequestered CO₂ (possible asset value), and the saline formation water.
• Underground injection control issues related to whether the state or the federal government should regulate such activities.
• Liability issues connected to potential leakage of the CO₂ under a variety of circumstances, including during the period of initial injection into the sink and during the post-injection period (involving possible fault zone or earthquake concerns), and the effect of transfers of property ownership.