The minimum amount of electric power needed to be supplied to the electrical grid at any given time.
Biodiesel
A fuel produced from oilseed crops such as soy, canola, and palm oil and from other oil sources such as waste cooking oil and animal fats.
Biofuel
A liquid or gaseous fuel derived from biomass, primarily ethanol, biodiesel, and biogas. Biofuels can be combusted in vehicle engines as transport fuels and in stationary engines for heat and electricity generation. They also can be used for heating and cooking.
Biogas
A gaseous mixture consisting mainly of methane and carbon dioxide produced by the anaerobic digestion of organic matter (broken down by microorganisms in the absence of oxygen). Raw biogas can be combusted to produce heat and/or power and also can be processed to become Biomethane/Renewable Natural Gas.
Biomass
Any material of biological origin, excluding fossil fuels or peat, that contains a chemical store of energy (originally received from the sun) and that is available for conversion to a wide range of convenient energy carriers.
Biomethane
See Renewable Natural Gas.
Carbon Intensity Score
Measure of lifecycle greenhouse gas emissions from a transportation fuel expressed in grams of carbon dioxide equivalents per megajoule of energy or gCO2e/MJ, which includes direct emissions associated with producing, transporting, and using the fuels.
Cellulosic Biofuel
Renewable fuel from cellulose, hemicellulose, or lignin that is derived from renewable biomass, with lifecycle greenhouse gas emissions of at least 60% less than lifecycle greenhouse gas emissions from its gasoline or diesel counterpart.
Clean Fuels Program
Oregon’s program to reduce the average carbon intensity of its transportation sector.
Disrupted Generation
Generation of electricity from dispersed, generally small-scale systems that are close to the point of consumption.
Drop-in Biofuels
Liquid biofuels that are functionally equivalent to liquid fossil fuels and are fully compatible with existing fossil fuel infrastructure.
Electric Vehicle (EV)
A vehicle that uses one or more electric motors for propulsion. A battery electric vehicle is a type of EV that uses chemical energy stored in rechargeable battery packs. A plug-in hybrid EV can be recharged by an external source of electric power. Fuel cell vehicles are EVs that use pure hydrogen (or gaseous hydrocarbons before reformation) as the energy storage medium.
Environmental Attributes
Environmental benefits, air quality credits, emissions reductions, offsets, and allowances attributable to energy generation by a renewable fuel source, e.g., RECs, RINs, and LCFS Credits.
Ethanol
A liquid fuel made from biomass (typically corn, sugar cane, or small cereals/grains) that can replace gasoline in modest percentages for use in ordinary internal combustion engines (stationary or in vehicles), or that can be used at higher blend levels (usually up to 85% ethanol, or 100% in Brazil) in slightly modified engines, such as those provided in “flex-fuel” vehicles.
Generation
The process of converting energy into electricity and/or useful heat from a primary energy source such as wind, solar radiation, natural gas, biomass, etc.
Geothermal Energy
Heat energy emitted from within the earth’s crust, usually in the form of hot water and steam. It can be used to generate electricity in a thermal power plant or to provide heat directly at various temperatures.
Greenhouse Gases (GHGs)
Gases that prevent heat from leaving the atmosphere by trapping heat that sunlight brings to the atmosphere, e.g. carbon dioxide, methane, and nitrous oxide.
Hydropower
Electricity derived from the potential energy of water captured when moving from higher to lower elevations.
Levelized Cost of Energy/Electricity (LCOE)
The cost per unit of energy from an energy generating asset that is based on the present value of its total construction and lifetime operating costs, divided by total energy output expected from that asset over its lifetime.
Low Carbon Fuel Standard (LCFS)
California’s program to reduce the average carbon intensity of its transportation sector.
Methane (CH4)
A greenhouse gas emitted by both natural and human-made sources, with a global warming potential 25-30 times more than carbon dioxide over a 100-year time frame, meaning a ton of methane will absorb 25-30 times as much thermal energy as a ton of carbon dioxide.
Municipal Solid Waste
Waste materials generated by households and similar waste produced by commercial, industrial, or institutional entities. The wastes are a mixture of renewable plant and fossil-based materials, with the proportions varying depending on local circumstances.
Net Metering/Net Billing
A regulated arrangement in which utility customers with on-site electricity generators can receive credits for excess generation, which can be applied to offset consumption in other billing periods. Under net metering, customers typically receive credit at the level of the retail electricity price. Under net billing, customers typically receive credit for excess power at a rate that is lower than the retail electricity price.
Obligated Parties
Refiners or importers of gasoline or diesel fuel under the RFS program.
Offtake Agreement
An agreement between a producer of energy and a buyer of energy to purchase/sell portions of the producer’s future production.
Offtaker
The purchaser of the energy from a renewable energy project or installation following an Off-take Agreement.
Percentage Standard
Annual percent of each renewable fuel type required by Obligated Parties under the RFS to either blend into their fuel or otherwise obtain RINs to demonstrate compliance with the RFS.
Power Purchase Agreement (PPA)
A contract between two parties, one that generates electricity (the seller) and one that is looking to purchase electricity (the buyer).
Renewable Energy Certificate (REC)
A certificate awarded to certify the generation of one unit of renewable energy. In systems based on RECs, certificates can be accumulated to meet renewable energy obligations and to provide a tool for trading among consumers and/or producers. They also are a means of enabling purchases of voluntary green energy.
Renewable Fuel Standard (RFS)
A US federal policy administered by the Environmental Protection Agency (EPA) which requires a certain volume of renewable fuel to be used in place of fossil-based transportation fuels.
Renewable Identification Number (RIN)
Manner by which obligated parties under the RFS demonstrate they have met their annual renewable volume obligation. Each RIN represents 1 ethanol gallon equivalent of replacement fuel. Once generated, RINs are entered into EPA’s Moderated Transaction System (EMTS).
Renewable Natural Gas (RNG)
Biogas derived from organic sources that has been cleaned to meet pipeline specifications, thus becoming interchangeable with conventional natural gas for all uses.
Renewable Portfolio Standards (RPS)
Policies that require electricity suppliers to supply a set share of their electricity from designated renewable resources or eligible technologies.
Renewable Volume Obligation (RVO)
The annual total volume of renewable fuels Obligated Parties must replace based on projections of gasoline and diesel production for the coming year under the RFS.
Solar Photovoltaics (PV)
A technology used for converting light directly into electricity via cells that use sunlight to separate electrons from atoms to create an electric current.
Solar-Plus-Storage
A hybrid technology of solar PV with battery storage.
Transmission Grid
The portion of the electrical supply distribution network that carries bulk electricity from power plants to substations, where voltage is stepped down for further distribution.
Virtual Power Purchase Agreement (VPPA)
An agreement whereby an Offtaker agrees to purchase a project’s renewable energy for a pre-agreed price. In this arrangement, the project receives the market price at the time the energy is sold. If the market price is greater than the fixed VPPA price, the Offtaker receives the difference. If the market price is less than the fixed VPPA price, the Offtaker pays the project to make up the difference.
Sources: EPA, Renewable Energy Policy Network for the 21st Century
