By Karolin Schaps and Nina Chestney
LONDON (Reuters) - Britain's energy secretary tried on Monday to reassure the public about shale gas fracking, downplaying any risk of groundwater contamination from the exploration technique but calling it no silver bullet to solve the UK's energy problems.
Edward Davey was speaking just weeks after protests erupted at a southern English exploration site owned by shale gas firm Cuadrilla Resources that led to the arrest of dozens of protesters including a senior politician.
"Today, I want to make the calm, rational, objective case for shale gas exploration in the UK," Davey said in a speech accompanying the publication of a report by the Department of Energy and Climate Change's chief scientific adviser.
The UK government estimates that Britain holds vast resources of shale gas, a fuel that has transformed the U.S. energy market by putting it on the road to energy independence.
Britain's finance minister has promised tax incentives for shale gas explorers, while Prime Minister David Cameron said unconventional gas has the potential to lower energy bills.
Some early shale gas drilling, however, resulted in earth tremors in Britain and environmentalists have said the technique pollutes groundwater.
"Shale gas could have significant benefits. But let me be clear, shale gas is no quick fix and no silver bullet," Davey said, adding that it was too early to establish what the impact could be on energy bills.
"We must make sure that the rigorous regulation we are putting in place is followed to the letter, to protect the local environment."
The chief scientific adviser's report also suggested that shale gas exploration in Britain should not hinder the country's ability to meet its climate change targets.
Britain aims to reduce its greenhouse gas emissions by 80 percent by 2050.
"Our study indicates that shale gas, if properly regulated, is likely to have a greenhouse gas footprint no worse than the other fossil fuels that society currently depends on," the chief scientific adviser, David Mackay, said.
The report estimated that the emissions intensity, or carbon footprint, of shale gas extraction and use is likely to be between 200 and 253 grams of carbon dioxide equivalent per kilowatt hour (CO2e/kWh) of chemical energy.
This compares to a 199-207g CO2e/kWh emissions intensity for conventional gas and 233-270g CO2e/kWh for liquefied natural gas.
Coal has an emissions intensity of 837-1,130g CO2e/kWh.
The report advised that the cost of low-carbon technologies, such as carbon capture and storage, should be reduced to ensure shale gas exploration does not increase emissions.
An international climate deal was also needed to help curb rising emissions, the report said.
(Editing by Dale Hudson)