Reducing Carbon From Coal

Two German projects are taking steps toward capturing and reusing carbon dioxide generated from coal-fired power plants.

In one project, BASF, Linde, and RWE say they have reduced by 20% the solvent-related energy costs of capturing CO₂ at RWE’s power station in Niederaussem, Germany. The advance, using new amine-based solvents from BASF, is crucial to climate-compatible coal power generation, the partners say.

A second project, just formed by Bayer, RWE, Siemens, and 10 German academic partners, intends to use some of the CO₂ captured in Niederaussem as a building block for chemical intermediates such as carbon monoxide and formic acid.

The first project, which has a $113 million price tag, has been testing CO₂ removal with the BASF solvents for more than a year. The partners plan to open demonstration plants by 2015 and the first commercial installation by 2020.

Bob McIlvaine, president of the environmental consulting firm McIlvaine Co., points out that the claimed 20% energy cost reduction applies only to CO₂ capture, in which the gas is absorbed into a solvent. It doesn’t include the energy required to compress and store the CO₂. By his calculation, the solvent improvement reduces the 40% energy penalty of power plant carbon capture and storage to about 33%, which he says is still a “pretty good” accomplishment.

Bayer will lead the second German project, called CO₂-Reaction using Regenerative Energies & Catalytic Technologies, or CO₂RRECT. It will have a $23 million budget, $14 million of which will come from the German government in grants over the next three years.

The partners envision a system in which surplus electricity from solar cells and wind turbines is “stored” as hydrogen that is generated via water electrolysis technology supplied by Siemens. The hydrogen can then be reacted with CO₂ to form building blocks for plastics and other chemicals.

If CO₂RRECT is successful, it will “make a valuable contribution to reducing CO₂ in the energy and chemical industries,” says Helmut Mothes, senior vice president of Bayer Technology Services.