CenterPoint Energy is asking state regulators for permission to set up a renewable natural gas pilot program, giving customers the option to pay extra so more of their natural gas supply comes from renewables.

Centerpoint’s Becca Virden says renewable natural gas comes from cleaned and refined methane and is, “Produced when organic waste breaks down in the absence of oxygen. So, for example, it can come from landfills, it can come from wastewater treatment.”

CenterPoint says if approved by the Public Utilities Commission, the utility would begin enrolling customers in late spring 2019 and have renewable natural gas added to what’s already in pipelines by the next heating season after that.