A decision on whether to go ahead with five wind farms in Powys will be made after the general election, the Department of Energy says.
Developments are proposed at Llaithddu, Llandinam, Llanbrynmair, Llanbadarn Fynydd and Carnedd Wen, as well as a power lines running from Llandinam to Welshpool.
Montgomeryshire MP Glyn Davies welcomed the delay, saying he was concerned about a rushed decision.
The plans have sparked protests.
The proposed developments are large scale and well above the 50 megawatt jurisdiction of the Welsh government and are instead dealt with by the UK government's Department of Energy and Climate Change (DECC).
A year-long public inquiry into the wind farms came to an end last May and was convened because Powys council refused to support their construction.
'Investment and employment'
Mr Davies said: "The decision will have huge implications for our wondrous landscape, and it would have been outrageous to rush a decision through before the general election.
"This deserves very careful consideration, and my objective has been to ensure it's not in any way rushed."
However, David Clubb, director of pressure group RenewableUK Cymru, said the delay would "inevitably postpone the investment, employment, training and community benefit funds which could be unlocked by these developments".
"We would have liked to see a decision ahead of the election, so the energies, enthusiasm and goodwill of industry, business and community could be harnessed to galvanise the economy of Powys as quickly as possible," he added.