Bioenergy in Oregon
Wood and Other Biomass in 2018:
- 331 MW of capacity
- 36 operating facilities
- Facility capacity ranges from 0.2 MW to 51.5 MW
- Facilities are in 16 Oregon counties
- Oldest came online in 1936, newest in 2015
Renewable Natural Gas in 2018:
- 51.1 MW of capacity
- 25 operating facilities
- 10-20% of state's total yearly use of natural gas could be replaced by RNG if potential is realized
Bioenergy or biomass energy—the energy
from plants and plant-derived materials—has been used since humans began
burning wood to cook food and keep warm.
Wood is still the largest biomass
energy resource today, but other sources of biomass can also be used. These
include food crops, grassy and woody plants, residues from agriculture or
forestry, oil-rich algae, and organic municipal and industrial wastes (that’s
right: poop). Even the fumes from landfills – methane, the main
component in natural gas – can be used as a biomass energy source.
Electricity generated from wood and other biomass fuels amounts to around 1.7 percent of Oregon’s annual
Biomass in Oregon
While Oregon has some
dedicated biomass energy crops, most biomass resources are secondary products,
such as lumber mill residue, logging slash, and animal manure. Examples of
biomass resources available in the Northwest include woody biomass, spent
pulping liquor (byproduct of pulp and paper making process), agricultural field
residue, animal manure, food processing residue, landfill gas, municipal solid
waste, and wastewater treatment plant digester gas.
Oregon has 17 woody biomass power facilities, primarily in the wood-products industry. An additional 21 facilities in Oregon use woody biomass to provide space heat; these include schools and hospitals.
Renewable Natural Gas
Some Oregon facilities currently generating biogas simply flare the biogas, while others burn it in a special
internal combustion engine that is connected to a generator that produces electricity. Those facilities either
consume that electricity on-site or sell it onto the grid through a Power Purchase Agreement with an electric
utility. Another option is emerging in Oregon: cleaning up biogas to meet natural gas pipeline quality
standards – at which point it is called Renewable Natural Gas (RNG) – and then injecting it into an existing
natural gas pipeline. The RNG can be sold as either a direct use stationary fuel or as a transportation fuel.
Oregon recently quantified opportunities to convert persistent, long-term waste streams into useful energy as
biogas and RNG. Municipal waste streams — garbage, wastewater, and waste food — and agricultural waste
streams like manure, all generate methane, a powerful greenhouse gas. Redirecting these waste streams into
controlled processes can capture and use the methane, reducing greenhouse gas emissions and air pollutants
when the resulting RNG is substituted for fossil fuels in our transportation and stationary fuels sectors. If
Oregon’s potential volume of RNG could be captured and used to displace fossil-based natural gas for
stationary combustion, we would prevent the release of approximately two million metric tons of greenhouse
gases into the atmosphere. Redirecting this fuel source into these sectors can also potentially result in
increased economic opportunity, and provide energy security and resilience for Oregon communities.
Biomass for Electricity Generation
The most common source of
biomass-based electricity is wood. The most common method of converting biomass
to electricity is through direct-fired combustion – a similar process to that is used for coal or natural gas. After the biomass has been pre-processed to remove
impurities, it is burned in a boiler to generate steam, which turns a turbine
and generates electricity.
Biomass power plants are
typically less than 50 megawatts in size, compared to coal plants, which are typically
200 to 1,500 megawatts..