to set the context, the following are excerpts from Wikipedia. it’s accurately written and contains some important points:
Renewable Energy Certificates (RECs), also known as Green Tags, Renewable Energy Credits, Renewable Electricity Certificates, or Tradable Renewable Certificates (TRCs), are tradable, non-tangible energy commodities in the United States that represent proof that 1 megawatt-hour (MWh) of electricity was generated from an eligible renewable energy resource (renewable electricity).
These certificates can be sold and traded or bartered, and the owner of the REC can claim to have purchased renewable energy. […] It is important to understand that the energy associated with a REC is sold separately and is used by another party. The consumer of a REC receives only a certificate.
In states that have a REC program, a green energy provider (such as a wind farm) is credited with one REC for every 1,000 kWh or 1 MWh of electricity it produces (for reference, an average residential customer consumes about 800 kWh in a month). A certifying agency gives each REC a unique identification number to make sure it doesn’t get double-counted. The green energy is then fed into the electrical grid (by mandate), and the accompanying REC can then be sold on the open market.
the US dept. of energy maintains a list of providers offering retail products and many, if not all, allow you to purchase a REC. as a retail consumer it is impossible to distinguish between electricity by it’s generation source (i.e. energy generated from coal and electricity generated by wind). in addition, many locations in the US have no renewable generation due to a number of possible reasons. buying many of these retail products do nothing to reduce one’s own carbon output. rather, the proceeds from the sale of these products become a subsidy or, as some have suggested, a “guilt payment”.
i would offer that if one wanted to contribute to the renewable cause, and it’s a good thing to do, one should invest in the provider and potentially receive a tangible dividend.
here are two retail products listed on the DOE site as an example — no endorsement intended:
- Good Energy — http://www.goodenergy.com/store/staticPages/National_Green_e_Certified_source_of_Supply_Green_e_12_Month_certificate.htm
- WindStreet Energy — http://www.windstreet.com/gift-cards.htm