ATLANTIC CITY, N.J. - An environmental group that strongly supports a proposed windmill farm off Atlantic City says New Jersey has the highest potential to develop offshore wind energy of any mid-Atlantic or New England state.

In a report released Monday, the Environment New Jersey Research and Policy Center says carbon pollution equal to 1.1 million cars could be eliminated by 2020 with a rapid expansion in wind power off the Jersey Shore.

"Offshore wind's potential off the Jersey Shore is still incredibly strong," said Doug O'Malley, the group's director. "The potential offshore of Atlantic City remains an untapped jackpot."

Get Breaking News Delivered to Your Inbox

The report says as much as 1,700 megawatts of wind power could be built in the state in the next five years if the state moves quickly. That would be enough to power more than half a million homes, the group calculated.

The report comes before an anticipated vote in the state legislature within the next week on an experimental wind farm off Atlantic City and appeared as an attempt to drum up support for the bill. It would permit -- but not require -- the state Board of Public Utilities to approve an offshore wind project off the coast of Atlantic City. A proposal by Fishermen's Energy would build a demonstration project three miles off the coast that could generate about 25 megawatts of electricity.

New Jersey energy regulators have rejected the plan three times, saying among other things that a Chinese company that would have owned 70 percent of the project did not demonstrate financial integrity. Fishermen's Energy says it has cut ties with that firm. The BPU did not immediately respond to a request for comment Monday.

Approval for such projects typically takes years, and in the region, only Rhode Island has begun one. That five-turbine project is set to open later this year. Under the recent pace of approvals, it is unlikely a project that has not yet begun could be open by 2020, although backers of the Fishermen's Energy project say it could be up and running within two years.

Offshore wind is a key component to New Jersey's goal of generating 22.5 percent renewable energy by 2021.

In November, two companies won the right to build windmills off the New Jersey coast to generate enough power for up to 1.2 million homes. The leased area runs roughly from Long Beach Island to the southern tip of the state near Cape May. Fishermen's Energy was among the bidders, but did not win.

A key concern for wind energy projects has been their affordability and whether they will need substantial subsidies to prevent the cost of the power they generate from being too expensive to make it viable.

O'Malley said a budget bill passed by Congress and signed into law by President Barack Obama last month will benefit the wind energy industry, with the five-year extension of a key clean energy tax credit that expired at the end of 2014, but will now run through the end of 2020.

The report calculated the wind energy potential of various coastal states, including offshore wind projects that have been issued leases by the federal government to begin commercial operations by 2020.

New Jersey's 1,700 megawatt development potential was followed by joint Rhode Island and Massachusetts projects at 1,000 megawatts; Maryland at 500 megawatts; and Massachusetts-only projects at 400 megawatts.

O'Malley said New Jersey has the most potential based on the large area off its coast approved by the federal government for wind projects (344,000 acres) and the strength of prevailing winds in those areas.