Lateline: Carbon capture and storage

EMMA ALBERICI:

The winds of change are blowing across Germany. By 2020, carbon-free energy sources like these turbines will be providing 30% of the country's electricity needs. But even with Europe's most ambitious targets for renewable energy, powering at least 70% of the lights in these towns will still involve burning coal, the number-one climate killer.

KATHARINA BLOEMER:

So we will use coal a couple of years more, and the world will not stop doing it. So we need to have some solution to the carbon dioxide problem.

EMMA ALBERICI:

At the Schwarze Pumpe coal-fired power station, it's a 10-million tonne a year problem. Vattenfall, the Swedish energy giant that owns the plant, thinks it has the solution. It's a whole new way of burning coal using pure oxygen, so it can't be retrofitted to old power plants. No electricity is actually generated here. They create carbon dioxide simply to show that they can capture 95% of it.

KATHARINA BLOEMER:

What happens behind the tanks is that the CO2 is compressed and cooled down until it reaches a temperature of minus-20 degrees and the pressure of about 20 bars. And that's the stage when it gets, actually, liquid.

EMMA ALBERICI:

Sir David King was the UK's chief scientist when the government commissioned Nicholas Stern to write his review on the economics of climate change. Three years later, he thinks CCS is too expensive and will take too long to prove at a full-scale power plant.

DAVID KING:

I don't think the technological solutions lie around managing carbon dioxide put into the air after burning fossil fuels. It's alternatives to fossil fuels that will provide the solutions.

EMMA ALBERICI:

Dr Rolf Kreibich is one of Germany's leading voices in the scientific debate around CO2 storage. What happens when CO2 is buried 1,500 metres or more into the ground? What does the science say about that?

TRANSLATOR:

What we know about gas stored 1,500-to-3,000 metres in the ground, pressed tight in a saline aquifer, is that it must be monitored. But it's difficult because gas goes up and down, but it also spreads across a large area sideways. And the scientific studies will show you it's not possible to adequately monitor the behaviour of CO2 underground.