Renewable Energy Certificates


A renewable energy certificate (REC) represents the environmental attributes or benefits of renewable generation such as wind, solar and geothermal power. 

Renewable power generation displaces less environmentally friendly generation that burns fossil fuels and causes air and water pollution. The electricity produced by renewable generation is comparable to electricity produced by conventional generation. But, displacing fossil fuel generation leaves a positive environmental impact.

As renewable generators produce electricity, they create one REC for every one megawatt-hour (or 1,000 kilowatt-hours) of electricity. RECs account for the associated attributes of renewable-based generation. Each REC includes the following information:

  • The underlying source of energy generation
  • The location of the generation facility 
  • The year of generation, or "vintage" 
  • Other characteristics associated with the generator, such as eligibility for state renewable portfolio standards (RPS)

On behalf of Greenpower customers, we retire the corresponding quantity of RECs associated with Greenpower megawatt-hour "sales" on an annual basis through the Western Renewable Energy Generation Information System (WREGIS).

Screen capture of EPA video "RECs: Making Green Power Possible"
Our Greenpower resource mix

This chart shows the resource mix1 in the RECs that we retired on behalf of our Greenpower customers in 2015. When Greenpower-funded projects do not generate the energy output commensurate with the customer contributions, the difference is balanced using our existing "bank" of RECs as a means of certifying the proper use of Greenpower funds. 

Renewables in the resource mix come from generation facilities that first began commercial operation on or after Jan. 1, 1997.

1Actual figures may vary according to resource availability. We will annually report the actual resources mix of the RECs retired on behalf of our Greenpower customers during the preceding year.

How we meet state renewable portfolio standards

Many states have a Renewable Portfolio Standard (RPS) requiring that renewable energy sources produce a specific amount of energy. A utility can meet this standard by either developing its own renewable energy facilities to produce RECs, or it can purchase RECs from others that own renewable energy facilities, such as solar electric generation or wind farms.

We have ownership in several renewable projects that produce RECs, so we're not currently purchasing RECs from outside sources.

Please note that voluntary participation in our Greenpower program supports the retirement of renewable energy certificates above and beyond those required by Oregon standards.

Here is a copy of our  current Oregon RPS Compliance Report.