Making Dirty Power Green: Is Carbon Capture a False Hope for Coal Power?

It's not easy being a power plant manager: Noboby wants to talk about the future of nuclear power at the moment. The memories of the public relations disasters that were the accidents at the Brunsbüttel and Krümmel nuclear power stations -- which saw both plants temporarily shut down last June -- are still too raw.

Even coal power, which still accounts for half of Germany's electricity production, has a problem: the greenhouse gas carbon dioxide (CO2). But at least here there is hope -- the so-called emissions free coal power plant. Using new CO2 capture technology, the greenhouse gas would be collected in the power plant before being transported elsewhere and stored permanently in an underground repository.

The technology, admittedly, is not yet far enough along to take up the mantle of saving the planet. At the moment, the focus is on getting it to work on a small scale. According to the Office of Technology Assessment at the German Parliament (TAB), CO2 capture will become available for large scale use in 2020 at the earliest. A new study by the TAB likewise comes to the conclusion that the cost of producing electricity using the new technology will nearly double -- instead of costing three to four cents per kilowatt hour, the price tag would rise to between five and seven cents.

Not surprisingly, the hike in costs will be passed on to consumers -- the price of fighting climate change, which will see both companies and customers digging deeper into their pockets. The real question, though, is whether carbon capture technology will make coal power impractical and unprofitable. TAB expert Reinhard Grünwald reckons that just 20 years from now, renewable energy sources, which are more expensive than conventional power sources today, will cost roughly the same as CO2-free coal power.

Tough Competition from Bio-Mass

"Water and wind are already, partly, in that price bracket. Geothermal and bio-mass power will also be in that price bracket by 2020," Grünwald told SPIEGEL ONLINE. According to the TAB study, seen by SPIEGEL ONLINE, emissions-free coal power plants will have to compete against other forms of electricity production that also produce little CO2.

Grünwald pointed out that CO2 capture is only economical if one has to pay to release carbon dioxide -- as is the case with carbon emissions trading schemes. The savings, he said, should lie at around €30 to €40 ($46 to $62) per ton of CO2. TAB reckons capturing the greenhouse gas will cost between €26 and €37 per ton of CO2. "This is the biggest cost," Grünwald explained, but one has to add transport and storage costs.

Despite all research attempts, CO2 capture technology still has its uncertainties. "Technologically, the whole thing is not resolved by any means," Jürgen Metzger, a chemist at the University of Oldenburg told SPIEGEL ONLINE. Speaking about underground storage, he warned: "It will have to be locked up safely; you only have to remember the latest earthquake in the Saarland" -- a February tremor in western Germany triggered by coal mining. He added that the CO2 capture technology had only been tested on a small scale so far.

Metzger also pointed out that capturing greenhouse gas takes a lot more energy, an extra 20 percent. To become environmentally friendly, power plants would therefore have to use up some of the electricity they generate, markedly reducing their efficiency. Metzger questioned whether it would even be possible to cost-effectively capture CO2: "Twenty euros per ton -- that is far too optimistic," he said. TAB's cost estimate of between €26 to €37 per ton was arrived at using calculations by several scientists.

A number of concepts have been developed in an effort to further the C02 capture idea. According to TAB, depleted oil and gas fields, as well as aquifers would be suitable as permanent storage places for carbon dioxide. So far, though, the TAB study has only been presented to a committee of the German parliament in Berlin.