The utility National Grid has reached a deal to buy electricity from the nation's first wind farm, planned off the coast of Cape Cod.
Under the 15-year contract announced Friday, National Grid would pay 20.7 cents per kilowatt hour starting in 2013 for electricity purchased from the 130-turbine Cape Wind project in Nantucket Sound.
The price would go up by 3.5 percent annually to keep pace with inflation.
The cost of electricity from conventional sources is about 9 cents per kilowatt hour.
The utility says the deal will add about $1.50 the average customer's monthly electricity bill in 2013.
The deal is considered crucial for financing a project estimated to cost at least $2 billion.
It must still be approved by state regulators.
This program aired on May 7, 2010. The audio for this program is not available.