The masterplan for the Eastgate renewable energy village has been amended by the Weardale Task Force, made up of One NorthEast, local authorities and site owner Lafarge Cement UK.
The size and siting of wind turbines has been changed because of their potential impact on the North Pennines area of outstanding natural beauty.
The resulting reduction in wind power has led to a proposal for a larger biomass plant, a spokeswoman for the task force said.
The scheme will include housing and business premises, a hotel, an education centre and a spa. It will use five types of renewables.
Eastgate project manager John Topliss said a planning application is due to be submitted early next year.