Wales is home to hundreds of wind turbines
The Welsh Assembly Government has "little hope" of hitting its 2010 renewable energy target, claims the Liberal Democrat environment spokesman.
Montgomeryshire AM Mick Bates said there was a "stifling lack of progress" in wind farm development.
The assembly government has pledged that it will increase green energy by 10% by 2010.
It said £6.5bn worth of renewable energy projects were either planned or underway in Wales.
But Mr Bates, speaking in his capacity as an AM, and not in his role as chair of the assembly's sustainability scrutiny committee, said there was "little hope" of reaching the green target set by officials in 2005.
He urged the assembly government to support companies in the wind sector suffering as a result of the economic downturn, which he said was happening in Germany and Spain.
Mr Bates added: "Times are clearly changing as the US has taken the lead in the production of wind power, while here in Wales with frustrating local objections we have seen a stifling lack of progress over the past few years."
He said at this rate the assembly government stood "little hope of reaching the 4TWh target under TAN 8, let alone more ambitious targets under the renewable energy route map".
In 2005, seven areas across Wales, known as TAN 8, were chosen for wind farm development.
The assembly government said it was committed to making Wales a "leading provider of green energy, produced not only by wind, but from biomass, marine and micro-generation".
A spokesman added: "Our renewable energy route map proposes that Wales could produce as much electricity as we currently consume from renewable sources within 20 years.
"Our database indicates that there are a considerable number of applications in the system for both onshore and offshore wind farms.
"There is £6.5bn of high efficiency conventional and renewable energy developments either proposed or underway in Wales and scheduled to come on stream.
"We are confident that considerable additional capacity will be provided over the coming years."
There are 26 wind farms in Wales with about 482 on-shore turbines and 30 off-shore.