Utility customers who want to install rooftop solar panels or small wind turbines could face extra charges on their bills after legislation passed the Oklahoma House of Representatives on Monday.

Senate Bill 1456 passed 83-5 after no debate in the House. It passed the Senate last month and now heads to Gov. Mary Fallin for her approval.

The bill was supported by the state’s major electric utilities, but drew opposition from solar advocates, environmentalists and others. It sets up a process at the Oklahoma Corporation Commission to establish a separate customer class and monthly surcharge for distributed generation such as rooftop solar or small wind turbines.

Customers who already have those systems installed wouldn’t be affected by the bill. It also wouldn’t apply to electric cooperatives, which aren’t regulated by the Corporation Commission. The new tariffs for distributed generation would start by the end of 2015.