Massachusetts’ highest court on Dec. 28 upheld an agreement allowing Cape Wind to sell power to National Grid, removing a major obstacle for the planned 130-turbine offshore wind farm on Nantucket Sound.

The ruling affirms the 2010 decision by the Massachusetts Dept. of Public Utilities (DPU) to allow National Grid to buy 50% of Cape Wind’s output — 234 MW. The Alliance to Protect Nantucket Sound, Associated Industries of Massachusetts, the New England Power Generators Association and TransCanada had appealed the DPU’s decision late last year.

In the 35-page ruling, Supreme Judicial Court Justice Margot Botsford called the DPU review consistent with state law requiring public utilities to buy 3% of their energy from renewable sources.

“Today is a really big day for Cape Wind and an even bigger day for clean energy in Massachusetts,” said Jim Gordon, Cape Wind president, in a teleconference. “This moves the project forward by creating up to 1,000 jobs and establishing Massachusetts as a global leader in offshore wind power.”

Although Gordon says the company hopes to begin construction within a year, the firm has not selected a contractor. Gordon says other companies have expressed interest in Cape Wind’s remaining power.

Energy and Environmental Affairs Secretary Richard K. Sullivan Jr. says the Massachusetts DPU’s original ruling assured that ratepayers could get renewable power at a fair price.

“Cape Wind will create local jobs, reduce our dependence on foreign sources of energy, and is poised to kick-start a new U.S. industry by making Massachusetts the site of the country’s first offshore wind farm,” Sullivan says.

The Alliance to Protect Nantucket Sound says it will continue to fight the case in other legal avenues.

The 15-year deal calls for National Grid to purchase half of the electricity generated by Cape Wind for 18.7¢ /kWh in the first year of operation with the price rising 3.5 % annually.

“It is difficult to compare a wind energy facility to other fossil fuel plants which have external costs that increase the cost of energy such as healthcare and military expenditures,” Gordon said.