In today’s blog, we’ll discuss Renewable Natural Gas (RNG).
What is RNG? It is an ultra-clean, ultra low-carbon natural gas alternative. As organic waste decomposes it emits methane gas, called biogas. RNG is sometimes referred to as ‘biomethane,’ a related term. Biomethane or RNG is simply biogas that has been cleaned up to remove impurities and match the quality of pipeline gas such that it may blend with, or substitute for, conventional natural gas.
Regional gas utilities and pipelines continue to work with farmers, developers, and local governments to capture and purify biogas that can be cleaned up to pipeline quality gas and injected into existing natural gas systems. In addition, new policies are being enacted across our region to promote and accelerate further development and adoption of RNG. Here are a few examples from across the region:
In BC, there are five operating biogas projects using agricultural waste, landfill waste, and curbside organic waste to generate about 250,000 Gigajoules (GJ) (equivalent to 237,000 Dth) of RNG annually. FortisBC already purchases and injects RNG into its existing system, as well as investing in and operating biogas upgrading equipment, and is building another RNG-producing facility at the Vancouver Landfill. When the facility begins operation in late 2021, it will double BC’s existing expected RNG supply.
On the customer side, FortisBC was one of North America’s first utilities to introduce a voluntary participation RNG Program in 2011. FortisBC customers can designate between 5 and 100 percent of their natural gas use as RNG and pay a premium on their bill. FortisBC then injects an equivalent amount of RNG into the FortisBC distribution system. Today, more than 10,500 BC homes and businesses are enrolled in the RNG program.
The provincial CleanBC plan, enacted in 2018, set an ambitious target of 15 percent RNG blend by 2030. Though not yet in force, it represents a major shift in how FortisBC needs to look at its gas supply. Ultimately, FortisBC expects to use a number of tools to reach this objective, but if required to fill the gap with RNG, this represents a greater than 30-fold increase in its current supply levels.
In Washington, the state legislature passed a law in 2019 that requires each gas local distribution company (LDC) to offer RNG to its customers and gives those entities the ability to introduce RNG into their standard supply portfolios, provided the cost of RNG does not increase customer costs by more than 5 percent. Washington gas utilities are currently working with Washington Utilities and Transportation Commission (WUTC) staff and other interested parties to develop RNG cost recovery rules, RNG program limitations, and RNG gas quality requirements.
Currently, there are five projects producing or soon-to-begin producing RNG in Washington state – two landfills and one multi-farm dairy-waste digester connected to Williams Northwest Pipeline and two wastewater treatment facilities connected to Puget Sound Energy’s (PSE) distribution system. These facilities are currently all committed to serving the vehicle fuel market, primarily in California. As the vehicle fuel market matures and reaches saturation, however, it is expected that landfill- and wastewater-sourced RNG will be redeployed to serve local utility demand.
PSE has held preliminary discussions with numerous developers seeking to complete RNG projects in western and central Washington and with various municipal and regional wastewater treatment plants and landfills that seek to create additional revenue streams and reduce their own carbon footprint. PSE is engaged in the physical and economic feasibility analyses necessary to interconnect approximately 12 viable RNG projects. PSE recently acquired the RNG produced and upgraded at the large regional Roosevelt landfill in order to serve its gas customers with a clean and renewable resource.
Other Washington utilities are also considering potential supply sources, and some believe they may be able to offer RNG directly to retail customers through opt-in programs by late 2020 or mid-2021. By 2025, as much as 2 percent of Washington gas use could be sourced from renewable sources, with a potential of 5 percent by 2030.
In Oregon, similar to Washington, a law passed in 2019 requires the Public Utility Commission to adopt RNG programs for both large and small gas utilities, enabling them to fully recover costs of integrating RNG into their systems. Up to 5 percent of a utility’s revenue requirement may be used to cover the incremental costs of RNG. The law also outlines goals for adding as much as 30 percent RNG into the state’s pipeline system by 2050. A 2017 study by Oregon’s Department of Energy showed a technical potential of recovering some 48 billion cubic feet (Bcf) of RNG within the state annually, an amount that could supply every home using natural gas in Oregon today with a local, renewable energy source.1
RNG development could reduce U.S. GHG emissions between 101-235 million metric tons (MMT) by 2040 – the equivalent of reducing GHG emissions from average annual residential natural gas use by 95% from levels observed over the last 10 years.2
Oregon’s first gas-grid-connected RNG facility, Threemile Canyon Farms in Boardman, began production in 2019, with a tie into the Williams Pipeline system. Three more projects have announced plans to interconnect to NW Natural’s pipeline distribution system, beginning with the City of Portland’s Columbia Boulevard Wastewater Treatment Plant and Shell New Energies’ Junction City projects in 2020, and the Metropolitan Wastewater Management Commission project in Eugene-Springfield in 2021. Like RNG producers in Washington state, these projects are earmarked to supply the California vehicle market for now, although some of the Portland RNG will power city trucks at a natural gas fueling station to be built at the treatment plant.
Idaho is entering the RNG game too. Intermountain Gas Company has already integrated RNG produced from one dairy farm in Jerome and is looking to bring others online as feasible.
Renewable natural gas is a unique resource. It allows us to capture streams of methane from the decomposition of human and agricultural waste that would otherwise be emitted directly into the atmosphere, clean it up, and put it to beneficial use. RNG significantly reduces greenhouse gas emissions. Furthermore, it allows for optimizing the use of the existing 128,000 miles of energy delivery infrastructure that serves warmth and comfort to about ten million people who live in the Pacific Northwest as well as produce energy for almost 350,000 businesses here.
- Biogas and Renewable Natural Gas Inventory SB 337 (2017), 2018. www.oregon.gov/energy