What about the Carbon?

From an environmental perspective, there are at least three major concerns about any coal-to-liquids proposal. First, a prodigious quantity of carbon dioxide is produced as a by-product of the Fischer-Tropsch process. Of the total carbon in the coal, only about half ends up in the liquid fuel product. The other half is turned into carbon dioxide, the global warming pollutant responsible for a majority of the human-caused climate change. The Fischer-Tropsch plant proposed for Roundup would produce about 3.5 million tons of carbon dioxide per year, with approximately 2 million additional tons coming from the IGCC plant.

The July 2005 issue of Scientific American described the situation as follows:

“In response to the growing demand for imported oil to fuel vehicles, some nations, such as China, are turning to coal to serve as a feedstock for synthetic fuels that substitute for gasoline and diesel fuel. From a climate change perspective, this is a step backward. Burning a coal-based synthetic fuel rather than gasoline to drive a set distance releases approximately double the carbon dioxide, when one takes into account both tailpipe and synfuels plant emissions. In synthetic fuels production from coal, only about half the carbon in the coal ends up in the fuel, and the other half is emitted at the plant.”

The emissions from the motor vehicles are important to consider. Renewable fuels, like biodiesel, partially “close the loop” with respect to carbon dioxide. In other words, the carbon that is released at the tailpipe started out as “atmospheric carbon” that subsequently became sequestered in growing plants (oilseed crops, switchgrass, etc.) through the process of photosynthesis. The combustion of this organic material returns carbon to the atmosphere that originated there—with no (or little) net increase in atmospheric CO2. In contrast, the carbon that is released through the combustion of petroleum, natural gas, coal, or synfuels is “geologic carbon” that was taken from the ground and then transported to the atmosphere.

The governor’s response to this concern is to say that the carbon dioxide from synfuel plants can be captured and then returned underground in a process known as “geologic sequestration.” The governor points to the Dakota Gasification Company (DGC) in Beulah, ND, as an example.

DGC produces synthetic natural gas from lignite coal using the Fischer-Tropsch process. For the last four years, the plant has successfully captured nearly all of its CO2 and transported it via pipeline 200 miles to the Weyburn oil field in Saskatchewan, Canada. The CO2 is then used for “enhanced oil recovery,” whereby hard-to-retrieve oil can be obtained from depleted wells through the injection of the pressurized gas, which then (ideally) remains in the ground. About one million tons per year of DGC’s CO2 is being sequestered in this fashion at Weyburn, which is currently the world’s largest sequestration project.

But carbon sequestration is not without costs or risks. Adding carbon capture and sequestration (CCS) to an IGCC plant can increase the overall cost of the project by 40% or more. And as is the case with radioactive waste from nuclear power production, the waste product has to be secured for an indefinite period of time. While using the CO2 for enhanced oil recovery improves the economics (its sale generates revenue to partially offset the cost of the CCS process), it offers less-than-ideal long-term storage prospects. Many old oil fields have drill holes that may not have been adequately mapped or capped, and the fields are usually closer to the surface than other more promising storage options. Also, in seismically active areas, large quantities of injected gas could increase the likelihood of earthquakes and potential releases.

Finally, while CO2 is not poisonous, it is an asphyxiant that has been known to kill people by displacing oxygen. In 1986, 1,700 people in Cameroon died when 300,000 tons of CO2 were released from Lake Nyos, due to an unusual but natural process.

According to Dr. Susan Capalbo of the Big Sky Sequestration Project, basalt formations in the Columbia River Basin offer a better repository for CO2 than oil fields. After being stored for a few decades in the basalt, the carbon dioxide is converted into an immobile solid form that no longer poses a leakage risk. Of course, piping millions of tons of CO2 from Montana to Washington State would require considerable infrastructure investment, and cause additional environmental disturbance.

The governor has argued that by helping to advance “clean coal” technologies (like IGCC or coal-to-liquids with sequestration), we can help steer developing countries like China and India in the right direction—in short, that we can somehow solve the global warming problem by digging more coal. Beyond the inherent illogic of that premise, these countries are already well aware of these technologies (in fact China is already investing $24 billion in coal-to-liquids plants). In the final analysis, coal-to-liquids does not bring the world any closer to solving the climate crisis. In a Congressional hearing held in April 2005, David Hawkins of the Natural Resources Defense Council testified that even if 90% of the carbon from a coal-to-liquids plant were to be captured and successfully sequestered, the “well-to-wheels” CO2 emissions would still be 8% higher than for petroleum production and refining.

What about the Water?