Biogas, biomethane, renewable natural gas, and responsibly produced gas – these are a few of the terms that folks in the energy sector use regularly and often group together under the 'green gas' umbrella. But what are they? Is there a difference between them? And are they all as clean and green as one another? Let's start with the basics.

What is Biogas?

Biogas is gas that is produced through anaerobic digestion, where microorganisms convert biomass to biogas in the absence of oxygen. It consists of roughly 60% methane and 29% carbon dioxide. Biogas is not high quality enough to be used as fuel for heating, cars, or most everyday activities due to its corrosive nature.

What is Biomethane?

Once biogas is processed and purified to nearly pure methane it becomes what is known as biomethane and is clean enough to inject into natural gas pipelines or to be used as 'clean' transportation fuel. Biomethane is also sometimes referred to as 'green gas' though this term is also used across the world to market products that bundle a number of different gas supply solutions.

What is Renewable Natural Gas (RNG)?

Renewable Natural Gas or RNG is another term for biomethane.

In North America, M-RETs developed—and is in the process of piloting—a renewable thermal certificate program. The M-RETS system is focused on RNG and biogas, with the certificates designated as renewable thermal credits (RTs). The system plans to have a public release on or before January 1, 2020. The renewable thermal tracking system aims to do the same thing RECs did for the renewable energy markets, and bolster investments in RNG development. These RTs are similar to what are known as 'biogas certificates' or 'green gas certificates,' which are utilized in countries across Europe to report lower emissions to initiatives, such as CDP and RE100 among other things.

It is widely accepted that biomethane, or RNG, is at the top of the list as the cleanest and 'greenest' in the gas space. However, there's one big problem: RNG supply is finite. It is estimated that if all in-state RNG resources were utilized, it would still only meet 2.5% of California gas consumption. Further, the current supply of RNG in the US would not even meet the state-wide demand of California alone. Estimates suggest that increasing a sustainable supply of biomethane significantly is possible, but it would only cover a small percentage of US demand. Therefore, although RNG seems like the ideal solution, we know it will not meet existing and increasing demand on its own.

So, how do we meet the remaining natural gas needs of the US that cannot be sourced via RNG? Continue producing at scale, business-as-usual, fracking shale, and degrading the environment? There's a better way.

Responsibly Produced Natural Gas

Believe it or not, there are natural gas producers actively engaging in extraction practices that take environmental impacts into account and are working to minimize them, while taking action to compensate for any degradation along the way. They're producing what's known as Responsibly Produced Natural Gas (RPNG). RPNG producers often have a significantly lower level of methane leakage than the national US average and engage in land reclamation activities at well sites. Additionally, producers often have water quality and water recycling provisions in place to ensure that the water used and/or produced during gas production is not contaminated when circulated back into the environment. Most importantly, RPNG producers have their wells third-party verified against certain environmental integrity benchmarks, while electronically tracking all production.

Knowing that RNG certificates, or RTs are not an all-encompassing solution given the constrained supply, we need to be investing in those producers who might not be producing RNG, but are consciously considering the environment in their extraction methods, and providing us the majority of the natural gas needed to meet our every day demand. Enter: RPNG certificates. These are certificates that represent 1 dekatherm of RPNG, now tradable on an electronic registry, making them a nearly identical commodity to RECs or RNG certificates, or 'RTs' as M-RETS is referring to them.

As an environmentally and emission-conscious organization with years of experience of working with companies in the energy sector, South Pole recognizes the challenges faced by gas providers and consumers alike. Although we agree that full electrification is the way in which the world should be headed, we recognize that dependence on natural gas will not disappear overnight.

We believe it is important to reduce emissions associated with gas usage as much as possible utilizing existing solutions and supply available to us today, and work on improving those solutions in the future, all while compensating any remaining emissions through the purchase of high-quality carbon credits from independently audited emissions reduction projects around the world.

That's why we've developed a product called EcoGas. It enables companies to offer carbon neutral gas to their customers, and make carbon neutral gas claims by combining the solutions described above to reduce and compensate emissions in the ways that make most sense in their particular market.

Now, with the development of RPNG certificates, we have taken this a step further to provide EcoGas+. This couples high-quality carbon credits and an RPNG certificate which together, represent 1 dekatherm of carbon neutral natural gas. This allows consumers to not only compensate for their natural gas emissions, but also provides an investment in cleaner and more responsible natural gas production, allowing producers to continue to lead the gas industry in the right, climate-smart, direction.

If you're interested in learning more about EcoGas or EcoGas+, please reach out to Erin Horleman at