CO2 Sequestration

They want to build what in Linden? A large coal power plant? You have to be kidding!! No, I am not kidding! The New York Times, The Newark Star Ledger, and TheAlternativePress have had a couple of articles about it this month and environmental activists all over the state of New Jersey are up in arms.

On Sunday, 18 October, I attended a lecture at the Essex County Ethical Society by Dr. Peter Montaque, the Executive Director of the Environmental Research Foundation in New Brunswick, NJ, and a member of the New Jersey Environmental Alliance. He explained the proposed project, a $5-billion, 750-megawatt coal power plant (although it apparently uses one-third of its electricity within the plant, so it generates 500 Megawatts for the grid) in Linden, NJ, called PurGen. Basically, it is to be a coal-fired, modern IGCC (Integrated Gasification Combined Cycle) electricity generator that includes CO2 capture and sequestration under the ocean 70 miles off the Jersey coast by Raritan Bay. Carbon Sequestration is the key element of this proposal and PurGen is considered by the coal industry a pilot project for carbon sequestration.

I have just learned that the Linden City Council has voted against the PurGen proposal by a vote of 7-4 at a scheduled official public meeting, Tuesday 21 October. Mayor Richard Gerbounka, an independent who is seeking re-election next year, lost this vote when the majority of the City Council sided with Democratic Council President Robert Bunk, also a mayoral candidate, in opposing a memorandum of understanding by the city with DuPont to open its 98-acre industrial property on Tremley Point for redevelopment. The approval of the memorandum would have included plans for the coal degasification plant. Probably this is not the last word we will hear about this controversial project, though.

Almost two years ago I attended a lecture by Prof. Gregory McCrea, MIT Department of Chemical Engineering, and a member of the team that wrote MIT's Coal Study entitled "The Future of Coal" that was published March 2007. He discussed the subject of new, cleaner coal power plants and CO2 sequestration. I was skeptical about burying pressurized liquid CO2 underground because I felt the possibility of CO2 leaks back into the atmosphere was dangerous and the technology had never been tested. At that time there were several proposals around the world to test CO2 underground sequestration in pilot-plant installations. Those tests have never been done, even up to this date in October 2009.

Our huge and powerful coal industry fears that it will die if the Senate approves climate legislation similar to the Waxman-Markey bill that passed the House. Although the House bill includes help for the coal industry, it also creates strong incentives for utilities to move away from fossil fuels. That leaves the coal industry with few options for a sustainable future.

"Unless they come up with a breakthrough technology to capture carbon and store it, coal is dying," said Kenneth Green, resident scholar at American Enterprise Institute, a conservative think tank. "If this [bill] does what they want it to do, I would say coal is on its way out." Permits and allowances for CO2 emissions will be made for the electric power industry, but they do phase out between 2026 and 2030. It seems clear to me and no doubt to the coal industry that if climate control legislation like the Waxman-Markey bill is passed and signed into law, then there will be no new coal power plants built in the U.S. unless they utilize CO2 sequestration.

The size and economic power of coal is huge. 92.8% of coal is used by the electric power industry. There are the equivalent of more than five hundred, 500-megawatt electricity-generating power plants in the United States with an average age of about 35 years (there are actually more than 600 but many are small). Nearly 800 mines produced 100,000 tons of coal in 2008. It takes railroads with over 160,000 miles of track to carry the coal to the power plants. There is, in addition, an inland waterway system with major coal trans-loading facilities. Passage of the House climate and energy bill last month kicked off renewed lobbying efforts by the coal industry in the senate, urging senators to produce legislation that would slow down the pace of efforts to cap carbon emissions. Environmentalists are pushing back, seeking to prevent a weakening of proposals.

The House bill, passed in a 219-212 vote, would limit carbon emissions and require businesses to buy permits for the greenhouse gases they emit. In the early years, the government would give away 85 percent of those permits and auction off the remaining 15 percent. Of the free permits, 35 percent would go to the electric utility industry in 2012 and 2013. The sector's free permit portion shrinks every few years after 2013. The allowances phase out completely between 2026 and 2030.

Both coal-industry and independent experts realize utilities must prepare for the shrinking number of free permits in the future. By switching from coal to natural gas, utilities could cut their carbon emissions almost in half because coal produces nearly twice as much greenhouse gases as natural gas, per unit of energy made.

Investors are not going to put money into coal-fired power plants or coal mines in the future as long as coal plants are the largest source of greenhouse gases and other toxic pollutants. Expansion of the coal industry in the U.S. is going to cease, I believe. No one is going to want to build a coal power plant unless they can collect and sequester its CO2 emissions. Otherwise, the only growth might be in coal sales to China or other countries.

Thus, the coal industry's hope is that it can find a commercially viable way to capture carbon emissions and sequester them underground or underwater. But putting the pieces of that technology together and getting them operating before the carbon cap tightens could be difficult. "You're talking about a minimum of 10 years" to show the feasibility of a carbon capture and sequestration plant, said Joel Darmstadter, senior fellow with Resources for the Future, a nonpartisan research group. Such a time frame may even be too fast when there is not yet a pilot project in the U.S. And building high-pressure pipelines needed to move the captured carbon will be virtually impossible, I believe, unless the pipelines are very short, preferably on the power plant property only.

I do not completely understand why the world has been so slow to build and test pilot plants for the collection and sequestering of CO2, although the global recession has certainly played a role. Such a technology would be very valuable even if the U.S. does not build new coal plants. We have hundreds of operating coal plants that would be candidates for retrofitting such technology. China continues to build coal plants, probably one or even two a week despite the fact that they are also building solar and wind power plants as well. With an increasing population and hopefully improving economics, the developing world will need all the clean electric power it can possibly build and CO2 sequestration could part of the mix of technologies used.

The method of geo-sequestration or geological storage involves injecting carbon dioxide under considerable pressure directly into underground geological formations. Declining oil fields, saline aquifers, and unminable coal seams have been suggested as storage sites. Caverns and old mines that are commonly used to store natural gas are not considered, because of a lack of storage safety.

In the North Sea, Norway's Statoil natural-gas platform Sleipner strips carbon dioxide out of the natural gas with amine solvents and disposes of this carbon dioxide by geological sequestration. Sleipner reduces emissions of carbon dioxide by approximately one million tonnes a year. The cost of geological sequestration is minor relative to the overall running costs. Right now, this appears to be the closest we have to an actual pilot program for the coal plant CO2 sequestration technology.

Both the MIT Coal Study and the proposed Linden PurGen plant, discussed earlier in this column, proposed the same technology for the capture of CO2 from the power plant emissions. Coal would be gasified and chemically changed to a "syngas" (mostly methane and CO2) and then the CO2 would be stripped out with an amine solvent (an ammonia derivative). About 90% of the CO2 is actually captured. The captured CO2 is pressurized to a supercritical (a kind of half-way phase between liquid and gas) thermodynamic phase and pumped away to the geological storage place.

The cost of this CO2 capture and pressurizing is an additional 30% of the cost of the electricity produced in this kind of power plant. This should not be surprising since there is more weight due to the added oxygen in the CO2 than the coal itself that is almost entirely made of carbon! In other words, more CO2 mass must be processed and pumped underground than the coal fuel itself. There will be considerable more cost that must be added to the electricity cost by the sequestration process and the necessary extensive CO2 monitoring process to test for leaking CO2.

Clearly a coal power plant with CO2 capture and sequestration is no panacea. It will not turn the ugly duckling of a coal burning power plant into a fairy princess. It requires mining with its attendant health, accident problems, and environmental problems. In fact, the National Research Council just issued a report that said that coal is responsible for 10,000 deaths per year. Coal burning still will be a polluter of toxic metals, and coal plants with CO2 sequestration still will emit about 10% of their CO2. They will still produce millions of tons of ash that become a considerable environmental problem. And there is the risk that the sequestered CO2 might escape bask into the atmosphere.

No one knows all the risks we take when millions of tons of CO2 is sequestered deep underground either under land or under the sea. There is the risk of earthquakes fracturing the rock between the CO2 and the earth's surface providing leak paths back up into the atmosphere. There is the risk of pipelines and valves leaking or breaking under pressure. There is the risk of water flows deep underground disrupting the stored CO2. There are many other risks I am sure. It is vital that the stored CO2 does not come back into the atmosphere because it will suddenly add to the "greenhouse" blanket and potentially cause an almost immediate rise in atmospheric temperature.

When there is a large leak of CO2 into the atmosphere from the ground, the CO2 displaces the air and becomes a great danger to animal life including humans. CO2 is tasteless, odorless, and invisible; if you were unknowingly to walk into a dense cloud of CO2 you would die within minutes due to a lack of oxygen.

The risk that CO2 sequestration might not be permanent is similar to the awful risk that most so-called geo-engineering solutions that hope to cool the earth have. If something goes wrong with the geo=engineering technology and the world has continued to emit CO2 as it does now, then the concentration of CO2 in the atmosphere will be very high. If the cooling has to be stopped because of technology problems, then the high CO2 concentrations will heat the earth to very hot and possibly deadly temperatures rather quickly.

Finally, I do not believe we have heard the last of PurGen in New Jersey, despite the Linden City Council vote. Maybe the power company will change the proposal somewhat and sweeten the pot for Linden and try again. Be on the alert!

 Phil Eisner writes about environmental issues.  He is a resident of Summit, NJ.

The opinions expressed herein are the writer's alone, and do not reflect the opinions of or anyone who works for is not responsible for the accuracy of any of the information supplied by the writer.

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