First coal plant ready to capture and store its carbon emissions opens

Posted by Laura Grant on September 11, 2008
Posted in Business

Depending on your perspective, the world’s first demonstration plant for carbon capture and storage (CCS) (CSS) technology, which was officially opened in Germany on Tuesday, is either a milestone for clean coal technology or a distraction that will delay investment in real clean energy technologies.

The 30MW plant, built by Swedish energy utility Vattenfall on the premises of its 1,600MW Schwarze Pumpe power plant in northern Germany, took 15 months and cost about 70-million Euros to build. It’s very small compared to conventional power stations, but it’s the first coal-fired power plant in the world ready to capture and store its own carbon dioxide emissions. And Vattenfall has bigger plans for the future.

Slashing emissions
Schwarze Pumpe is one of a number of old East German power stations that burn lignite (brown coal), which is the dirtiest form of coal because it’s still damp and produces much more polluting soot when burned, says SciAm.

At Vattenfall’s new CCS plant, the carbon dioxide emitted when the lignite burns will not be vented up a chimney into the atmosphere, but compressed to a liquid and “further treated for long-term secure underground storage”, then pumped into porous rock deep below the surface. The concentrated carbon dioxide will be injected into the depleted Altmark gas field, about 200km from the power plant.

The outcome of this new plant will be heat, water vapour and nine tons of carbon dioxide per hour, Markus Füller, a spokesman for Vattenfall, was reported as saying.

“The development of the CCS technology can make a decisive contribution to reducing carbon dioxide emissions, as coal will continue to play a significant role in the worldwide energy supply for a long time to come,” Vattenfall said in a statement.

Tuomo Hatakka, the chairman of Vattenfall Europe said: “With our pilot unit we are demonstrating that coal and high-tech do not represent a contradiction.”

Oxyfuel
The pilot plant uses an oxyfuel boiler, which involves burning coal in pure oxygen and carbon dioxide rather than normal air. “By stripping out the nitrogen and other gases, the burning coal produces mostly water vapour and nearly pure carbon dioxide. After condensing the water, the carbon dioxide can be bottled and pumped underground (in this case, into an old natural gas field to get even more methane out of the ground),” according to SciAm.

But, stripping nitrogen out of air reportedly requires a significant chunk of the energy produced by the burning of the coal in the first place. And this is one of the issues raised by critics of the technology.

Another concern is that it is not yet known how secure the storage of carbon dioxide in rock is. Some critics of CCS CSS say that it could take as long as a decade to establish a strong scientific basis for the reliability of this kind of storage.

The cost of CCS CSS is another stumbling block. Caps on carbon emissions in the European Union may make the process viable there. But a Reuters report quoted an analyst as saying that CCS could add about $1 billion to the capital cost of a full-scale power plant and this cost may be passed on to consumers in higher power prices.

German conservation group BUND has denounced the Schwarze Pumpe CCS CSS project as “a cover allowing Vattenfall to expand its network of conventional coal-fired power stations in Germany”.

Some environmentalists argue that power utilities should concentrate on developing real clean technologies, such as solar and wind, and that CCS CSS is being used as an excuse to continue building coal-fired power stations.

Oxyfuel is one of three CCS methods, the other two are pre-combustion, which entails the removal of carbon dioxide before burning by pre-treating the coal, and post-combustion, which scrubs the exhaust gases from a power station.

The Schwarze Pumpe pilot will run for three years initially, according to reports. Vattenfall plans to build two more bigger “demonstration plants” in Germany and Denmark by 2015 at the latest. And it aims to commission its first “large-scale CCS power station” in 2020.

CCS CSS in South Africa
Eskom will be following the progress of the Schwarze Pumpe demonstration with great interest.  Just over 90 percent of the country’s electricity is generated from coal, which contributes significantly to the country’s high per capita carbon dioxide emissions. The minister of environmental affairs and tourism, Marthinus van Schalkwyk, announced in July that no new coal-fired power station would be built in South Africa that was not ready for carbon capture and storage. This affects the two massive new coal-fired power stations to be built by Eskom in the next few years – Poject Bravo, a proposed 5,400MW plant near Witbank and Medupi, a 4,800MW plant in Limpopo province.

But even if the German plant is a success, CCS CSS may not be a viable option for South Africa. A report by Creamer Media’s research channel states that South Africa “does not have much in the way of suitable subterranean strata on land to store the excess carbon dioxide”.

Pictures courtesy Vattenfall

Sources: Climate Ethics.org, Scientific American, Guardian, Deutsche Welle, Vattenfall, Reuters, Business Report, CARMA

Comments

One Response to “First coal plant ready to capture and store its carbon emissions opens”

  1. Laura Grant
    March 20th, 2009 @ 8:54 am

    Oops, got tangled up in the acronyms.

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