November 4, 2010 - what kinds of generation make up Maine's standard offer mix?

Today, a break from recent blog entries about dam removal in Maine, New Hampshire, and Massachusetts, for a refresher on the mix of generation resources serving the average Maine electricity consumer.  Each electricity supplier tends to source its electricity from a variety of generation assets.  In Maine, thanks to utility deregulation over the last decade, our three largest investor-owned transmission and distribution utilities don't actually generate or sell you the electrons you consume.  Rather, competitive electricity providers compete (in theory) to provide "standard offer service", meaning default electricity supply service.  Consumers are free to select other competitive providers to supply their electricity, but must make an affirmative choice to do so.  Otherwise, most consumers, particularly residential consumers, take standard offer service.


The photo above shows a recent mailing I received at my house detailing the power source mix for the current standard offer provider for customers of Central Maine Power's T&D network: NextEra Energy Power Marketing, LLC.


You can see that the largest share of power sourced by NextEra in 2009 was hydro (30.9%), with gas a close second (29.2%) and nuclear power (basically, Seabrook) at 24.5%.  In total, 33.5% of NextEra's energy supply came from sources meeting Maine's renewable portfolio standard requirements.  By contrast, the average New England mix is more heavily weighted in gas, nuclear, and coal, with renewable sources playing a much smaller role.

The generation mix is not simply an academic question; it has implications for other policy choices.  For example, we've seen in past entries how the generation mix can affect other environmental claims, like what kind of emissions are associated with electric vehicles.

Interestingly, the supply mix is slightly different from the last time I got a notice.