LIPA’s proposed wind farm would produce less power than touted 

The Long Island Power Authority’s plan for a 90-megawatt wind farm off the coast of Rhode Island, if approved, would actually bring 75 megawatts of power to the South Fork because of previously undisclosed capacity limitations on the electric grid.

People briefed on the plan say the 75-megawatt figure is described as the “maximum” net amount of power that it could deliver to East Hampton because of limitations of the South Fork power grid, including an East Hampton connection station, and power degradation over the 30-mile cable.

In responses to Newsday questions last week, LIPA spokesman Sid Nathan confirmed the 75-megawatt figure, saying the project is “designed so that it can limit its peak energy delivery to 75 megawatts if necessary based on the lowest possible ability of the (East Hampton) substation to accept energy at any time of peak production.”

A megawatt of offshore wind power can provide enough energy for around 320 homes, according to the American Wind Energy Association, an industry group in Washington, D.C., meaning the 15-turbine array would power around 24,000 homes. The project will consist of 15 General Electric turbines rated at 6 megawatts each.

On July 14, LIPA announced what it billed as the country’s largest offshore wind farm, even though other projects propose considerably larger energy production and some are already conducting needed studies. U.S. Wind, for instance, has already begun sea-bottom studies for a 750-megawatt wind farm 12 miles off the coast of Maryland, which it expects to be in production by 2020 – three year’s before LIPA’s proposed Dec., 2022 start date.

Nathan suggested LIPA’s project off the Rhode Island coast could ultimately deliver more than 75 megawatts. “As contract and engineering details are finalized, we anticipate the substation will likely be able to accept more than that,” he wrote, without elaborating.

Construction of the wind farm is expected to cost around $700 million, a figure LIPA disputes, and PSEG Long Island is expected to spend more than $500 million in South Fork grid upgrades to improve reliability and accommodate the wind energy. LIPA, PSEG and Deepwater have declined to discuss costs, but Newsday previously reported that South Fork power solutions would cost LIPA $67 million to $90 million and the net customer bill impact for all residential customers would be $2.48 a month, though LIPA said the incremental bill impact is $1.20 a month.

LIPA would pay only for energy from the farm, expected to start at slightly more than 16 cents a kilowatt-hour.

LIPA has been relatively quiet about the project since the New York State Energy Research and Development Authority asked that it cancel a board meeting to vote on it July 20, saying New York wanted to complete a statewide blueprint for offshore wind energy.

It’s not just technical issues that will limit the wind farm’s output. While the wind in the waters off Rhode Island is considered optimal, it isn’t blowing all the time. The so-called capacity factor for offshore wind projects, including those estimated off the U.S. East Coast, is generally between 40 percent and 45 percent, meaning that the project can be expected to produce energy around just under half the time, said Hannah Hunt, a senior analyst at the American Wind Energy Association. NYSERDA documents list the area as having a 44.8 percent capacity factor.