Frequently asked questions
- RNG is a carbon neutral energy source that essentially recycles carbon that is already circulating in the environment. Unlike the burning of fossil fuels, which is the release of new carbon emissions that were previously sequestered in the earth, RNG is derived from captured methane that otherwise would be released into the atmosphere.
- RNG displaces fossil fuel, thus allowing us to rely less on foreign fuel.
- RNG does not require the growth and harvest of crops for its production.
- RNG is distributed through the existing infrastructure.
- RNG production at dairies creates useful, environmentally-friendly byproducts.
- RNG, when used in the transportation sector, yields up to an 85% reduction in lifecycle GHG emissions in comparison to conventional diesel.
Renewable Natural Gas is biogas derived from organic sources that has been cleaned to meet pipeline specifications, thus becoming interchangeable with conventional natural gas for all uses.
No. RNG truly is derived exclusively from naturally-occurring, organic sources.
Although we can take steps to diminish sources (e.g., reduce food waste), organic matter has always, and will always, produce methane as it decomposes. RNG keeps methane out of the atmosphere and instead puts it to a beneficial use.
Motivations behind the production and use of RNG have no bearing on the science. Aggressively fighting climate change requires us to deploy a diverse range of renewable energy. RNG, and other sources of renewable energy, all have a part to play.
Market dynamics of those two industries drive their creation, independent of RNG facilities.
Despite the fact that landfills and farms typically operate under strict air and water pollution regulations, there are instances where practices have adversely impacted local communities. The purpose of RNG facilities is not to provide bad actors the opportunity to point to something positive while engaging in behavior that is detrimental to the environment.
RNG facilities typically make site hosts more, not less, aware of environmental rules and regulations.
Although methane does not last as long in the atmosphere as carbon dioxide (10 years versus hundreds of years), it is indeed a greenhouse gas that has a higher Global Warming Potential (GWP) than carbon dioxide. Capturing methane at the source (e.g., landfills, farms, and wastewater treatment plants) keeps it from being emitted into the atmosphere. Combusting RNG does create carbon dioxide emissions, but since RNG is derived from plants (which naturally remove carbon dioxide from the atmosphere), the carbon dioxide emissions arguably are climate-neutral.
Waste is a climate change issue. We waste enough food each year to feed the food insecure many times over. Before a discussion about whether organic matter should be diverted, it first needs to be acknowledged that reducing waste at the source has societal and environmental benefits and should be the first step taken. Thereafter, using organic matter to create compost or for animal feed are viable options, but do not completely negate the need to convert biogas into RNG. Even in Seoul, South Korea, where 95% of food waste is kept out of a landfill, a certain percent of that organic matter stills goes to producing RNG.
No. There is, however, enough RNG production potential to displace up to 25% of conventional natural gas.
RNG projects have varying cost structures depending on a variety of factors, including ultimate use. The costs of developing RNG-to-pipeline projects range from $7.10-$32.60/MMBtu. The costs of developing RNG electricity generation projects are approximately $1,500/kW, which is comparable to other renewable energy sources.
Aside from the fact that this is likely not achievable any time soon, it’s arguably not even advisable given that using RNG to fuel appliances in a typical US home generates fewer GHG emissions on a lifecycle basis compared to a home using all electricity when the grid generating that electricity is over 75% carbon-free.
There is no doubt that pipelines have been known to leak to some degree. Estimated leakage from the US natural gas infrastructure has been estimated to be 0.38%. Accounting for leakage, the benefits of RNG’s GHG emissions’ reductions would only be diminished by 5%. Additionally, both for financial and environmental reasons, utilities are incentivized to minimize leaks.

