A deal to extend the Bush-era tax cuts also includes action on ethanol and biodiesel credits, U.S. Sen. Chuck Grassley, R-Iowa, said Tuesday.

The details aren’t clear yet, but Grassley told reporters that the ethanol and biodiesel tax credits would get a temporary extension, through 2011.

The biodiesel credit of $1 a gallon expired last year, and farm-state lawmakers have blamed the expiration for the idling of biodiesel plants.

The ethanol credit, at 45 cents per gallon, is scheduled to expire at the end of the year.

Grassley said the biodiesel credit extension also included applying it retroactively to 2010.

Many of the details of the tax compromise aren’t known. U.S. Sen. Tom Harkin, D-Iowa, said Tuesday he didn’t know whether the tax credits were in the deal or not.

Critics have argued the renewable energy credits are wasteful and are pushing for their expiration.

However, farm-state lawmakers and ethanol lobbyists have argued the subsidies help lessen dependence on foreign oil and support thousands of jobs.

Grassley said he didn’t know the details of the deal, specifically at what level the credits would be set.

There has been some debate about lessening the ethanol tax credit to 36 cents per gallon. Farm state legislators are pushing to keep the credits from being reduced.