July 1, 2011

Bad Gas Policy

By Robert Peltier, PE

The late Dr. Carl Sagan once observed, “We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology (S&T).” I would add that those who know the least about S&T are often the ones responsible for determining policy and funding priorities. One good example of this problem is the piecemeal approach taken to developing carbon capture and sequestration (CCS) technologies.

CCS: A Four-Step Process

Let’s assume the end game is a fully developed and reliable CCS infrastructure capable of handling the gaseous CO₂ emissions from existing and future fossil plants. If so, then the CCS system requires the simultaneous development of four distinct links in the technology supply chain: CO₂ must be stripped from the syngas (in the case of an integrated gasification combined-cycle plant) or exhaust gas (from conventional coal plants); CO₂ must then be compressed; CO₂ is then transported through pipelines to storage fields; and CO₂ is injected into underground storage facilities. All four processes must work in concert if we wish to sweep CO₂ under the rug, so to speak.

Both the development of commercial processes to strip CO₂ from gases and geologic characterization work are in progress. Compressing the CO₂ without using a third of the plant’s output remains a technical challenge requiring intense research and development. Noticeably missing is any substantive work on either the cost or policy formulations for interstate transportation of the gas from disparate sources to injection points.