The Backbone Campaign is putting its ambitious community solar project on hold after a two-year effort by organizers that has proven far more complex than they had envisioned and has yet to generate enough investors to pay for the $540,000 project.

But Bill Moyer, Backbone Campaign’s executive director, said he’s not walking away from the concept of community solar. He said he’ll now turn his energy toward trying to fix a state law that he says is poorly written and has made the vision of investor-backed solar projects increasingly difficult to realize in communities across the state.

“Rather than give up on community solar entirely, … I am changing strategy to address what I believe are the reasons our community solar project proved too difficult,” he said in a letter emailed to a number of community members.

The problem, he said, is that the state-backed incentives for investors are slated to sunset in 2020, a “ticking clock” that makes the project a race against time and that jeopardizes projects that take longer to get off the ground or start later. What’s more, he said, it’s not clear what happens in 2020 when the incentives end but the array is still capable of generating power.

Because of the complexities, he said in an interview Thursday, it was hard to explain the project to potential investors. “People’s eyes just started glazing over,” he said. “It’s too complicated.”

As a result, he added, he wasn’t able to tee up enough interest in the project. He started working to secure investors — community members willing to invest $1,000 or more in the project — last August, after the state Department of Financial Institutions gave the project the OK it needed to begin solicitations. Since then, he said, he’s gotten enough commitments to cover about 20 percent of the project’s costs — “not enough to take advantage of the economies of scale necessary to deliver the size array and return on investment worthy of our community members.”

But Moyer said he still hopes he’ll be able to make a community solar project happen on Vashon.

“I’m pushing the pause button on the project in order to fix the program. I can’t promise the community I’ll fix the program, but I’ve already invested a great deal of energy and two years of work, and I understand the shortcomings of this as well as anybody — and the promise of it,” he said.

The project was slated to be installed at the King County Transfer Station on Vashon’s west side, making it the first community solar project to secure King County support. Bob Burns, deputy director at the county’s Department of Natural Resources and Parks, said the county continues to hope the Backbone Campaign will be successful in bringing the project to fruition.

“We hope that Bill and his group can pull together the funding and investment to make the project go,” Burns said. “We’re very interested in seeing it happen.”

Moyer’s vision for a broad-based community solar project — called Vashon Community Solar — was first announced at an Earth Day celebration at Vashon High School in April 2011. At the time, he and Gib Dammann, an islander and home designer, were working together to try to make the project happen, an effort to take advantage of both federal and state laws designed to kickstart the solar energy industry by attracting investors who could finance projects on public buildings or properties.

Since then, the project has garnered a lot of interest, including strong support from top King County officials. County Executive Dow Constantine, in a news release about the county’s partnership with Vashon Community Solar, praised what he called a “creative partnership” that could “help us reach our ambitious, but achievable, goal of meeting half of the energy needs of county government from renewable sources.”

Moyer contracted with Carol Eggan, a former airline executive who has a solar array at her own home, to try to get the project off the ground. In November 2011, she said, she hoped to see the project installed by the spring of 2012.

But many issues got in the way or slowed the project down, from finding a site for the project, to crafting an agreement with the county once the site was identified, to securing a green light from the state to allow organizers to begin seeking investors. In the process, the project grew more complex; the state, for instance, said Vashon Community Solar could get an exemption from complex laws governing financial securities but at the same time added a caveat that only people who had an affiliation with the Backbone Campaign could become investors.

Early on in the process, meanwhile, Dammann decided to go his own way, saying he wanted to pursue a smaller project that had a simpler financial structure. His project, Vashon Solar LLC, one-fifth the size of the one the Backbone Campaign has proposed, was just installed at The Harbor School and will likely go online next week.

“We’re good to go,” he said Friday.

Dammann, however, said he understood Moyer’s frustrations. He was able to complete the $100,000 project — supported by 15 investors kicking in $5,000 or more per person — in part because he and his wife were able to put $30,000 towards the project, purchasing equipment early enough to take advantage of a federal tax grant. Still, he said, getting his much smaller project over various state and federal hurdles has proven extremely hard.

“If I’d known it was going to be this difficult, I don’t know if I would have done it,” he said. “But it got to the point that I had so much time and spirit invested in it, I had to see it through.”

The two state laws that created the incentives to support investment in community solar projects were passed in 2009 and 2010. Moyer, however, said the laws have several fundamental flaws because they tried to address competing goals. The legislation, for instance, was meant to “maximize solar investment” but only if the project used arrays manufactured in Washington, much costlier equipment, he said. What’s more, he added, the purpose of community solar isn’t clear: Are community members donating funds toward a cause they believe in or making an investment for which they can expect a return?

“When you confuse the two, it gets very difficult,” Moyer said.

Moyer has already begun to talk to lawmakers and legislative staff in an effort to see if new legislation can be crafted. He’s also scheduled to speak at a gathering in mid-January put on by Solar Washington, a nonprofit made up of solar energy equipment manufacturers, dealers, designers, consultants and others interested in the industry.

His interest, he said, is in “systemic change,” laws that could make community-backed solar far more achievable.

“Rather than push the boulder up the hill, I’d like to try to make it easier for the next people who want to do this,” he said.