The cheapest RECs were offered by Texas Wind and New Jersey Class I.
Meanwhile, RECs from Massachussets Vintage topped $30 in July of 2009, Pike Research found, citing data from Evolution Markets.
One REC even fetched $650.
The report shows that about 115 retail and wholesale companies operate in the REC marketplace.
About 84 percent of the RECs are certified by Green-e, which tracks them to avoid double-counting.
Pike Research predicts that a national renewable energy policy would spur compounded annual growth of 16.7 percent in the REC market.