Coal-burning plants are the world's biggest producers of electricity. But as climate change worries mount, the billions of tonnes of greenhouse gases they emit each year have put in doubt coal's future as a cheap, home-grown source of electricity.
The United States, through its FutureGen project, had hoped to help change that by developing the world's first full-scale nearly emission-free coal plant in Downstate Illinois. But with the billion-dollar project in financial restructuring and on hold, a small pilot plant in Spremberg is now spearheading the global push to make coal a clean fuel.
Built alongside a traditional power plant, the German test plant burns dirty brown coal with pure oxygen rather than air to produce nearly pure carbon dioxide emissions. Those emissions are then condensed, liquefied and pumped into long-term storage, eventually in old gas fields or salt aquifers several kilometres below the earth's surface.
If the technology proves itself in trials over the next three years, it could turn coal into a relatively clean fuel, dramatically reducing the world's energy worries and its climate concerns. That would give coal-rich nations like the United States, China, India and Russia the ability to produce abundant electricity without contributing significantly to climate change.
"We don't think there is one silver bullet. But this is the biggest tool we have to combat climate change," said Lars Stromberg, vice president for research and development for Vattenfall, the Swedish power company that operates the new 30-megawatt plant.
Electricity from such "carbon capture and storage" plants would initially be half again as expensive as current coal power. But if a system of carbon emission caps and trading credits is developed worldwide in the coming years, as most experts expect, the cost of producing electricity with the new technology would soon be on a par with old-style electrical production, researchers predict.
In a world where 80 per cent of energy still comes from fossil fuels and where renewable energy sources are still being ramped up, carbon-capture plants could serve as a technological bridge that cuts global greenhouse gas emissions by 15 to 20 per cent, helps the United States achieve greater energy independence and allows cleaner development in nations such as China and India that plan to build hundreds of new coal-fired power plants in coming years, experts say.
"Without (carbon capture and storage), we are lost," said Brick Medak, an energy expert with the World Wide Fund for Nature in Berlin. "We don't believe it's a long-term solution. In 60 years we hope we will have an energy supply based on 100 per cent renewables. But for the forthcoming 30 or 40 years, it's a bridging technology."
Worldwide, a number of trial carbon capture and storage plants, using a variety of technologies, are in the pipeline. Twelve are planned in Europe. The United States' main project plant, however, planned in Mattoon, Illinois, was put off for financial reasons early this year.
The Spremberg plant, a privately funded effort, is the first coal burner to effectively begin capturing more than 95 per cent of carbon dioxide emissions. The $US100 million ($A130.43 million) facility will at first store liquefied carbon dioxide on site and then transport it by truck 355 km to a largely depleted gas field in northern Germany. Eventually Vattenfall officials hope to build a pipeline to carry the waste to below-ground storage.
The company, which operates coal-burning plants around Germany, decided to build the test plant at its own expense largely in an effort to hold onto its market and meet a self-set commitment to reduce its emissions by half by 2030. Germany, like a growing number of countries, has banned construction of new traditional coal-fired power plants in an effort to hold the line on ever-rising greenhouse gas emissions.
With scientists warning that large-scale cuts in greenhouse gas emissions are quickly needed just as growth in countries such as China is pushing emissions dramatically higher, "somebody needed to take the initiative and not just talk," Stromberg said. "If we wait for research centers and government money, it'll be too late. We have to do research at this scale now or we'll never get to the big plants."
