Colorado state Rep. Chris Hansen plans to introduce a production mandate for renewable natural gas, as a newly released report shows major carbon-reduction benefits.

“I think it’s a great opportunity for the ag sector. You have right now what is a waste product that has to be mitigated,” said Hansen, D-Denver. “You can get some fertilizer value out of it depending on the situation, but it’s something that right now is a cost center. This would be a great way to turn that resource into a revenue source.”

Biomethane sources include farms, landfills, wastewater, and food waste. 

The Colorado Energy Office found that renewable natural gas could substitute for approximately 24% of diesel fuel consumption in the state, which would eliminate 1.4 million metric tons of carbon dioxide emissions.

“To date, however, Colorado’s RNG potential remains largely untapped,” the report stated, indicating that the only present and planned facilities to create renewable natural gas (a.k.a. biomethane) are at wastewater plants.

RNG is interchangeable with conventional natural gas, but its greenhouse gas emissions are lower over its lifetime. Producing RNG makes use of organic matter already in the ecosystem, rather than releasing methane into the atmosphere through previously-untapped sources.

Transportation in Colorado accounts for 29% of all energy consumption, the largest category of use. The number of natural gas-using vehicles in Colorado more than doubled between 2008 and 2016. RNG would still use pipelines for delivery, and the report identified landfills in 17 counties-with 13 landfills currently collecting biogas-as well as livestock populations where chicken, swine, and beef/dairy cattle manure could convert to fuel.

Hansen’s proposal would also address natural gas delivered to buildings, modeling a biomethane mandate on the state’s renewable energy standard.

“You’d set a percent by a certain date that would have to be sold and to allow the market to come back with RFPs so the customer gets the best deal,” said Hansen. “That’s the concept I’m looking at. Use that model to encourage this market.”

In 2004, Colorado became the first state to enact a renewable portfolio standard by ballot initiative. The law requires investor-owned utilities to produce 30% of their electricity with renewable power by 2020.

The Colorado Energy Office has since reported that utilities are on track to meet the goal.