Pembrokeshire Council has urged an energy company to choose the county to locate its £800m gas power station.
RWE npower said it was aiming to start work on the plant this year
RWE npower is examining sites at Pembroke Dock and in Nottinghamshire.
The council said it had a "highly skilled" workforce and the plant, which would create at least 100 permanent jobs, would secure Pembrokeshire's place as the "energy capital of Wales."
Friends of the Earth Cymru said it wanted to see a "more efficient" power station than the one being proposed.
RWE npower has already obtained planning consent for a gas-fired plant at Staythorpe near Newark, Nottinghamshire.
An application for one at the site of the former power station at West Pennar in Pembroke Dock is currently with the Department of Trade and Industry.
The company said it would create around 100 permanent jobs when up and running with up to 1,000 employed during the construction stage.
Pembrokeshire council's deputy leader John Allen-Mirehouse said the authority had been in talks with the company for some time and was keen to attract the investment to the county.
"One hundred well paid, highly skilled jobs, would be very welcome and experience has shown us a similar number could also be employed by contactors," he said.
He said Pembrokeshire had a proven track record of working with large energy companies both with the oil refineries and liquefied natural gas (LNG) plants currently under construction near Milford Haven.
"One point worth making is it will provide the security of a good clean electricity supply for the south Wales industrial belt," he added.
"It will consolidate our position as the energy capital of Wales.
"I hope most sincerely that they do the right thing and locate in Pembrokeshire."
The plant proposed for Pembroke Dock would be powered by natural gas supplied from the nearby LNG terminals to produce electricity.
Gordon James of Friends of the Earth Cymru said: "Gas is certainly a cleaner fuel than coal and is certainly a step in the right direction."
However, he said the type of plant proposed was not as efficient as combined heat and power generating stations.
"Climate change is a real crisis that needs to be addressed as a matter of urgency and with this type of power station there is a lot of wasted heat.
"We must maximise the efficiency of the fuels we use to reduce waste."