Federal regulators are considering a new electricity pricing system for New England.
The plan is aimed at promoting the development of new power plants in the region to meet increasing energy demands.
It replaces a federal proposal that sparked controversy last year because it allowed power companies to charge more in high-demand areas.
The plan would create auctions at which power plants would bid against each other to provide power.
Massachusetts Attorney General Tom Reilly says it will force New England ratepayers to shell out an additional five billion dollars through 2010 with no guarantees that new plants will be built.