Campaigners opposed to fracking are writing to First Minister Carwyn Jones and Prime Minister David Cameron to highlight their worries after the Chancellor signalled his support for the industry in yesterday's Budget.
It is thought there is a substantial amount of gas under parts of South Wales, and many local people are concerned about the controversial way it is extracted.
Those representing oil and gas operators have welcomed George Osborne's comments.
Hannah Thomas has been listening to both sides of the argument.
Evidence will be given to the Environment and Sustainability Committee later on a controversial method of shale gas extraction more commonly known as fracking.
Those giving evidence include the environmental lobby group Friends of the Earth Cymru, and the group applying to test drill in south Wales UK Onshore Gas Limited.
The Director of Friends of the Earth Cymru is expected to promote the focus on renewable energy over the use of fracking.
To protect Wales from climate catastrophe we must impose a moratorium on unconventional gas extraction, as has already happened elsewhere in Europe. And we should move as swiftly as possible to a Wales powered by 100% renewable energy, providing tens of thousands of jobs in the booming green economy.
– Gareth Clubb, Director of Friends of the Earth Cymru
A public meeting's been held in Cardiff to discuss the possible consequences of testing for shale gas around the South Wales coastline. If successful, the tests could lead to a controversial process known as fracking. Hannah Thomas reports.
Energy Minister Ed Davey has spoken to ITV about the UK Government's decision to go ahead with gas exploration in Lancashire using hydraulic fracturing. He says communities should be reassured. Just because a company says it wants to go 'fracking' doesn't mean it will go 'fracking'.