In the US's latest congressional budget – which should be signed off before Christmas – onshore wind projects that begin construction before the end of 2020 will be able to secure production tax credits (PTC).
It means developers have a 12-month reprieve to get projects up and running rather than face an end of year rush to secure the credit.
The proposed extension to the investment tax credit (ITC), which supports offshore wind and solar projects, was left out of the bill, as was the introduction of support for storage projects.
The American Council on Renewable Energy (Acore) said its supports the "modest extensions" in the budget package, but it was a "squandered opportunity".
"This is not the time to be kicking the climate can down the road," said Acore CEO Gregory Wetstone.
"If we're going to have any chance at reducing greenhouse gas emissions to the level that scientists say is necessary, we need smart policies to accelerate the ongoing transition to a renewable energy economy and a modernised, 21st-century grid," he added.