Farm-Based Anaerobic Digestion to Catalyze Decarbonization

Food and beverage waste can be combined with manure from farms in anaerobic digesters to produce renewable natural gas (RNG).

The need to offset the use of fossil resources and meet strict low-carbon fuel and renewable energy regulations is increasing the demand for renewable natural gas (RNG). While solar and wind energy are the most commonly known renewable energy sources, RNG is gaining ground. According to a 2018 study by Southern California Gas Co., converting less than 20% of the fossil natural gas in U.S. pipelines to RNG can significantly reduce greenhouse gas (GHG) emissions (1). The International Energy Agency (IEA) highlights RNG development as a critical pathway to net-zero emissions by 2050 (2).

According to the Coalition for Renewable Natural Gas, as of 2021, there are 157 operational RNG production facilities in North America, and an additional 110 RNG production facilities under construction or that have completed substantial development (3). Vanguard Renewables has seven operating RNG facilities in the Northeast and more than 20 under construction or being permitted nationwide. Our goal is to have RNG facilities in the 20 most populated U.S. cities by 2025.

A rough estimate of the energy that could be produced by anaerobic digestion at full market capacity is 300 trillion Btu/yr, which is equivalent to about 20% of the total energy demand in the U.S. (4). As our atmosphere is increasingly impacted by fossil fuel use, RNG production offers a way to reduce our carbon footprint and limit our environmental impact. This article details how farm-based RNG production can help to achieve our energy and emissions goals.