The Rhode Island Department of Environmental Management, Office of Air Resources, adopted Air Pollution Control Regulations 46 and 47, rules establishing a carbon trading program and a mechanism to auction and sell carbon allowances. The regulations apply to any unit that has served as an electricity generator with a nameplate capacity equal to or greater than 25 MWe since January 1, 2005. The carbon trading program will go into effect July 22, 2008. http://www.dem.ri.gov/pubs/regs/regs/air/4647dec.pdf.