Electricity generated from renewable energy resources continues to grow its share of the U.S. market, according to a recent U.S. governmental report. While most renewable energy sales are motivated by renewable portfolio standards -- state laws requiring utilities to source specified amounts of energy from renewable resources -- a small but growing amount of electricity is sold in voluntary green power markets.
Consumer demand for renewable-sourced electricity has led to voluntary markets in which consumers and institutions voluntarily purchase renewable energy to meet their electricity needs. These markets include green power offers, competitive supplies, and over-the-counter renewable energy certificate (REC) sales. According to the National Renewable Energy Laboratory's report, Status and Trends in the U.S. Voluntary Green Power Market, in 2012 voluntary retail sales of renewable energy represented approximately 1.3% of total U.S. electricity sales, or about 48 million megawatt-hours. According to NREL, these sales represent the power produced by about 17,000 megawatts of installed renewable capacity.
While the voluntary renewable electricity market remains relatively small in absolute terms, it is growing rapidly. NREL's report found that from 2010 to 2012, total green power market sales increased by 36%, for a compound annual growth rate of 1%.
In 2012, the resource mix supplying renewable energy to the voluntary renewable market was dominated by wind energy, at 80.1% of total green power sales. Other resources in the mix include landfill gas and biomass (12.8%), hydropower (6.2%), solar (0.6%), and geothermal (0.3%). Like the entire voluntary market itself, solar power is a small but growing segment, experiencing a tripling of market share between 2010 and 2012.
For now, despite its recent growth, voluntary retail sales of renewable energy represent a small fraction of power sold. The vast bulk of renewable energy is sold in compliance markets, established pursuant to state renewable portfolio standards or targets. Will voluntary markets continue to grow? How will proposals to increase state standards affect the voluntary markets?