RENEWABLE NATURAL GAS

A recent study, conducted by ICF Consulting through the American Gas Foundation, estimates the technical potential of renewable natural gas supply is substantial when compared to current natural gas throughput. In fact, when looking at development costs and existing technologies, the report estimates there is enough potential renewable natural gas to achieve a 95% reduction in emissions in the residential sector.

The supply estimates from the ICF report do not include the potential for renewable hydrogen for the pipeline network or the impacts of deep energy efficiency to reduce future energy use. With these collective innovations pursued together, the company believes a carbon neutral vision for the gas pipeline network is possible.

The California Air Resources Board found that when made from food waste or farm waste in anaerobic digesters, biomethane—or RNG—is net carbon-negative over its lifecycle, meaning that we can reduce more emissions by injecting RNG into our existing pipelines. If all the homes currently heating with conventional natural gas switched to RNG, we could easily and dramatically reduce current GHG emissions.

Not only can RNG slash GHG emissions compared to fossil gas, it also improves air quality, since it is nearly pure methane and burns much cleaner than fossil gas. The more carbon-negative RNG carried in our natural gas pipelines, the more the climate impacts of existing natural gas infrastructure will be reduced.

In the spring of 2019, Summit Natural Gas of Maine launched a landmark RNG program to further the company’s commitment to building a sustainable energy future. As part of that program, we matched 5% of our residential gas demand for one year with RNG attributes at no cost to our customers to help reduce our carbon footprint.

With approval from the Public Utilities Commission, we began giving our customers a renewable choice when it comes to their home heating needs by allowing them to match 10% to 100% of their average annual gas usage with voluntary RNG attributes. This program is helping to jumpstart the renewable biofuels market and spur investment in new technologies that mitigate of the impacts of climate change.

Summit launched a state-of-the-art RNG development project. While still in development, Summit is partnering with family dairy farms throughout central Maine to turn the manure from their dairy operations into RNG. The renewable attributes from the digester will be sold to third parties to help them meet their emissions reduction goals. We anticipate that the digester will supply approximately 125,000 MMBtu of gas a year. To put that in perspective, that is about 45% of our annual residential demand in Maine.

In Arkansas, Summit purchased 100 percent of the gas created at the Fort Smith, AR Landfill. That means we transported 628,660 MMBtu of RNG on our system.