NASA's chief climate scientist James Hansen has written to Prime Minister Kevin Rudd urging him to halt the building of coal-fired power stations unless they can capture carbon emissions.

ESAA chief executive Brad Page says the Government's role is to set a clear emissions target and put a price on carbon emissions.

"If they put a price on CO2 emissions and set a target for both the medium term and the long term the market will soon work out whether it makes sense or not to build new coal-fired power stations," he said.

"Most of the conventional wisdom at the moment is that it is most likely, until carbon capture and storage is available, new coal-fired plants are unlikely to be built. In fact they are more likely to be gas-fired."

Mr Page says it is up to the market, not governments, to choose the right technologies to reduce carbon emissions.

"It's a very difficult transition period to 2020, depending on just how big those emission cuts have to be," he said.

"But beyond there, there will be many new technologies that will dramatically change the footprint of electricity generation in this country, so in the medium to longer term we're very confident."

Source: By Australian Broadcasting Corporation