In Vineyard Power’s humble headquarters just past the Grange Hall on State Road in West Tisbury hangs a dry erase board with a breakdown of the Island’s energy meters. One number stands alone in bold: 824. It’s the most important number to the fledgling energy cooperative, the number of members who have signed up so far.

“If those 824 members all get one person to join, we’d be up to 1,600,” said Vineyard Power director Richard Andre, eyeing the board. Credibility, both in the community and among investors, depends on membership.

Sporting an “Ask me about Vineyard Power” T-shirt and the weary but relieved expression of a local summer survivor, Mr. Andre said the energy cooperative is entering the most crucial stage of its existence. Just coming off of the seasonal summer push, the organization now boasts a complete board of nine directors, after the August election of Chilmark selectman Warren Doty, as well as two heavy hitters in the worlds of law and finance: Bill Lake, head lawyer for the Federal Communications Commission, and Ron Dagostino, vice president at State Street Global Advisors. It represents the organization’s desire to be both of the community while possessing the corporate and legal firepower of a utility company when it goes to compete in the open market.

In the coming weeks, Vineyard Power members will be sent an online survey to gauge their response to visual simulations of turbines at various distances. As early as January or February, Mr. Andre said, using that member feedback, the cooperative is preparing to bid on lease blocks in federal waters south of the Vineyard where, by as early as 2015, it hopes to develop upwards of 17 turbines to supply enough energy to power the entire Island. The plan is to stabilize and even lower energy prices for members, all the while keeping an additional $17 million on the Island that would have otherwise gone to off-Island energy suppliers.

“We’re entering into one of the most critical stages: picking sites,” Mr. Andre said. “If that’s not an incentive to join, I don’t know what is.”

Another incentive is the price of a membership, which jumps from $100 to $150 on Oct. 1 (The price will reach $975 in 2015; by then Mr. Andre claims the benefits will be too compelling not to join).

After a sluggish end of spring and start to summer that saw membership stall at around 700, and community forums which struggled to attract even a handful of prospective members, Mr. Andre said the organization is back on track, signing up two to five new members a day. He attributes the newfound momentum to the organization’s forays into road association meetings and outreach efforts at Cronig’s and around the Island.

“This summer was a huge learning curve,” he said. And despite the fact that in the spring the cooperative had announced a membership goal of 2,000 by the end of 2010, he said the organization is still on schedule.

“I’d love to get 2,000, but if we were above 1,000 or 1,200 I’d be really, really happy for our first year,” Mr. Andre said. He said the real number to watch is 3,600 by the end of 2011, which has been the main goal all along. Eventually the cooperative hopes to enlist 10,000 members.

“We just have to remind ourselves it’s still the early days,” he said.

With the prospect of cooperatively-owned wind turbines still years away, Mr. Andre said that either next year or the year after, Vineyard Power plans to build one to three large solar projects on the island.

“With the wind turbines, we’re essentially asking members to buy into a vision,” he said. “With these solar projects, we’ll deliver benefits to our members now.”

In addition to the ongoing membership campaign the summer also saw the rise of an increasingly vocal segment of the Vineyard community wary of wind development, culminating in a forum in August sponsored by the community group POINT. The skeptical segment does not worry Mr. Andre.

“[POINT director] Andy Goldman is a member of Vineyard Power,” Mr. Andre said. “If you ask him why, he says he’s not necessarily against wind but he’s all about the process and ensuring that the Island has say in the waters around the Island — that it’s not all done from Washington, D.C. or Boston. That’s what Vineyard Power is all about.”

Even when Mr. Andre is swamped with the day-to-day labor of getting an energy utility on its feet — the organization is beginning to turn its attention toward the chamber of commerce and signing up Island businesses — when discussion turns to the prospect of an Island of electric cars powered by its own wind turbines, a rapt, distant look comes across his face.

“It’s going to happen, man,” he said, nodding his head. “It’s going to happen.”