Alternative FuelRNGTransportation Professionals
Renewable Natural Gas' Role in a Clean, Low-Carbon Future
In the race towards decarbonization, many stakeholders have adopted the “electrify everything” mindset – believing it to be the fastest, cleanest way towards zero emissions. Backed by consumers, governments, and organizations alike, solar, wind, electric, and hydrogen have emerged as the preferred solutions in replacing fossil use. However, while viable, alone, they cannot bring the change many seek – a change that has so far been driven by what many consider to be a transitionary energy source: renewable natural gas (RNG). Keep reading below to see where the market is today and learn how it will continue to grow – in part, thanks to renewable natural gas.
An Analysis of the Market: Current State
As of December of 2020, the U.S. Energy Information Administration (EIA) identified natural gas as the market leader for primary energy production and consumption by source – accounting for roughly 2.97 and 3.27 quadrillion BTU respectively. In the same categories, renewable energy only accounted for 1.02 and 0.99 quadrillion BTU. However, depending on the sector, each has a different energy source that accounts for the most consumption. Natural gas is the market leader for the industrial sector, petroleum for transportation, and electricity for residential and commercial use.
“Electrify everything” supporters may be encouraged seeing electric use led in two sectors; however, not in the way many imagine. While electric results in zero tailpipe emissions in transportation applications, depending on its feedstock, lifecycle emissions may unveil a different reality. For 2021, the EIA projects only 22% of electric power generation will be sourced from renewables and hydropower, as shown in the below graph.
Specifically, CARB noted that California’s average, grid electric used within the transportation sector for 2021 has a CI score of 75.93 – one that comprehensively, is neither carbon neutral, nor carbon negative. So, you ask – how can electric become as sustainable as many believe it to be? By leveraging renewable natural gas.
Future Potential of Green(er) Solutions
To meet stated climate targets and carbon neutrality goals, stakeholders need to consider lifecycle emissions: those that result from the production, transportation, distribution, and end-use of a fuel. In many cases, those emissions from the production phase are often overlooked when pitching the sustainability appeal of solutions – giving way to commonly held misconceptions. However, this doesn’t have to be the case.
Renewable natural gas, made by capturing, cleaning, and conditioning methane from agricultural facilities, landfills, and wastewater treatment plants, is not a fossil fuel – despite what many believe. On the contrary, it is the only carbon-negative solution on the market, namely in the case of diary based renewable natural gas. Seeing it prevents methane from otherwise entering the atmosphere as a potent greenhouse gas, significant emissions can be averted in initial stages of production.
Also, able to be transported through nearly three million miles of existing underground pipeline, some emissions can further be avoided during the transportation phase with the gas not needing to always be trucked from one location to another. However, aside from being used as a separate fuel type, boasting its unique, negative emission reductions, it can be leveraged in conjunction with other fuels – enhancing their sustainability appeal as well.
As we saw above, electric can be sourced from countless feedstocks: natural gas, coal, nuclear, or renewables – each resulting in differing sustainability levels. Relative to renewables, in 2020, the EIA found 8.4% of U.S. electric supply was generated from wind, 7.3% from hydropower, and 2.3% from solar. But the question remains, why did renewable natural gas not comprise a percentage greater than these three subsections? Especially considering that when produced from dairy gas, renewable natural gas can boast a carbon intensity score that’s 200-300% lower than that of battery-electric vehicles powered by solar or wind technology.
Therewithin lies the first opportunity for renewable natural gas: being leveraged to generate electric – whether that be for the transportation sector, residential or commercial use, or for industrial applications. Instead of being sourced from a fossil fuel or renewable options that don’t boast maximum emission reduction potential, organizations and governments can use renewable natural gas as a feedstock for their electric supply. This enables them to displace fossil use and lower the CI of their electric by targeting emissions during the production phase – extending beyond just its zero tailpipe emissions.
However, electric is not the only solution stakeholders are adopting for their transportation needs. Many are beginning to turn to hydrogen: another alternative fuel boasting zero tailpipe emissions. In the case of hydrogen, there are two principal ways renewable natural gas can be leveraged: during production and transportation.
To produce hydrogen, it is either done using steam methane reformation (SMR) or electrolysis. But, due to the expenses associated with electrolysis, SMR is the preferred method – accounting for roughly 95% of hydrogen production. During this process, since hydrogen is just an energy carrier, it must be produced from a primary energy source. This is where renewable natural gas comes into play and can be leveraged as a feedstock – replacing fossil feedstocks such as conventional natural gas, coal, nuclear, and beyond. During SMR, the methane (CH4) present in renewable natural gas reacts with steam, subsequently producing a lower CI hydrogen (H2) alternative.
Additionally, there is potential for RNG to be leveraged in the distribution of hydrogen. Because of hydrogen’s low density, both moving and storing hydrogen in its gaseous form can pose challenges and result in it becoming more costly than it’s worth. However, stakeholders in Europe are beginning to evaluate the potential of transporting hydrogen through the existing network of natural gas pipelines. If blended with renewable natural gas, the prior inefficiencies are no more, and the transportation of hydrogen could be streamlined.
As governments, policy makers, and OEM’s transition towards a zero-emission future, renewable natural gas will not be a solution that becomes obsolete. Instead, with growing supply coming online annually, renewable natural gas can be leveraged to further enhance the sustainable appeal of zero tailpipe emission options: inclusive of electric and hydrogen. While market shares of natural gas-based fleets may fluctuate in certain sectors or applications, the demand for renewable natural gas itself is telling of a different story.
To learn more about the applications of renewable natural gas in a clean-future or learn how it can be integrated in your existing suite of solutions, contact us today.