Greens want new power station plans to be abandoned after research suggested carbon capture and storage technology was "not feasible at any cost".

Earlier this week energy company Ayrshire Power submitted proposals for a new multi-fuel plant to be built near the current Hunterston B nuclear plant.

The plant aims to use carbon capture technology to trap environmentally-damaging carbon dioxide gas which is released in the burning of coal and then pipe it underground.

The application is the first in the UK for a new power station burning coal since rules forcing all new plants to be fitted with the technology were introduced last year.

But today Green MSP Patrick Harvie said the research paper, which was published in the in the Journal of Petroleum Science and Engineering, had left carbon capture technology "holed below the waterline".

The paper, by Christine Ehlig-Economides of Texas A&M University and Michael Economides of the University of Houston, stated: "Our very sobering conclusion is that underground carbon dioxide sequestration via bulk CO2 injection is not feasible at any cost."

The experts said when applying carbon capture and storage to commercial power plans, an underground area the "size of a small US state" would be needed to store the carbon dioxide.

They stated: "The findings of this work clearly suggest that it is not a practical means to provide any substantive reduction in CO2 emissions, although it has been repeatedly presented as such by others."

And Mr Harvie said: "The fact is that this technology and SNP plans to rely on it, have been holed below the waterline.

"This research concludes that burying the CO2 from a full size commercial power station would require underground storage roughly the size of a small US state - a luxury we simply do not have - and that it can not be made feasible at any cost."

He added: "This research has not been commissioned by the environmental movement - these are the practical conclusions of engineering specialists with a background in the oil and gas sector."

And he said the paper showed there was "no quick fix" when tackling emissions and that "the only truly clean power Scotland can rely on comes from renewables".