When The Hardware Store Restaurant gets its next bill from Puget Sound Energy, Melinda Sontgerath, its owner, will face higher costs for the electricity the bustling eatery consumes.

And she’ll pay it happily. In fact, Sontgerath requested the more expensive energy — becoming, it appears, the first restaurant in PSE’s huge service area to agree to purchase 100 percent of her energy as “green power,” renewable energy that her dollars will help to bring into the grid.

And while hers is the first restaurant, she’s hardly alone. Vashon, it turns out, is one of the biggest participants in PSE’s Green Power program, an innovative effort to finance alternative energy sources that has won accolades among renewable energy advocates.

More than 400 homes and 18 businesses on Vashon — 7 percent of PSE’s Island customers — have signed up for the Green Power program since its inception six years ago. That compares to 2.1 percent in PSE’s entire service area, 5.6 percent in Port Townsend and 6 percent on Bainbridge.

“It just came down to a personal choice,” Sontgerath said of her decision to participate in the program. “I was willing to make a little bit of a sacrifice to do what I think is right. If everyone does this, it just multiplies, and then we’re in a much better place as a country.”

Dr. Kelly Wright, a Vashon naturopath and another Green Power participant, signed up for the program years ago, shortly after it started. She did so, she said, because of the connection she sees between human and environmental health and her desire to see her daughters grow up in a cleaner world.

“I thought it was a very small investment for a great return,” Wright said.

PSE’s program is one of 600 across the country that enables customers to essentially vote with their pocketbooks — agreeing to pay a little more to ensure that the energy they consume comes from renewable sources.

Rob Harmon, chief innovation officer and senior vice president at the Bonneville Environmental Foundation, compares it to making the choice to purchase an organic apple at the grocery store. It costs more, he notes, but the consumer is doing something good for his or her family, supporting a cleaner environment and helping to build a market for organic produce.

Indeed, in the complex world of energy — where the government has a say in how much a utility can charge its customers and where renewable energy is still costlier than coal — such green power programs are one of the only ways to bring renewable energy into the marketplace, Harmon said.

Harmon, who coincidentally lives on Vashon, should know. About a decade ago, as a renewable energy consultant, he came up with what is called the “green tag” program — the precursor to the hundreds of green power programs now offered by utilities today.

Here’s how these programs work. When customers agree to purchase green power, they’re saying they want the amount of energy they consume to come from renewable sources, thus requiring the utility to purchase that same amount of renewable energy and put it into the grid.

But in so doing, they’re also helping to finance some of these cutting-edge — and more expensive — technologies. Each time a customer asks for green power, he or she is buying what are called “renewable energy credits.” A company can then use the money from those credits, along with conventional financing, to undertake the higher costs of developing and producing renewable energy.

As both the technology and the infrastructure that support renewable energy grow, the costs start to come down — an essential component to shifting energy consumption away from carbon and towards renewables, Harmon said.

“It’s essential to drive these technologies down the cost curve and to bring dollars into these kinds of programs,” he said.

Renewable energy will only “come to scale,” he said, when it’s as affordable or more so than coal. And that will happen, he added, only if communities collectively invest in renewable energy.

“The reason I came up with the green tags idea is that I was frustrated that I couldn’t choose to have 100 percent renewable energy,” Harmon said.

Noting that some say Puget Sound Energy should simply be doing this on its own, he added, “The issue isn’t why isn’t Puget doing all of this. … The issue is, do I have a choice voluntarily to do more because I want to take responsibility for my energy.”

In PSE’s case, Harmon’s organization, Bonneville Environmental Foundation, acts as a broker, purchasing the lion’s share of PSE’s renewable product from various sources. And in so doing, he said, the organization uses criteria it developed from three environmental groups, including the Natural Resources Defense Council, to screen the sources and ensure they’re meeting the highest environmental standards. What’s more, PSE’s program is professionally audited and is overseen by the Washington Utilities and Transportation Commission.

“There’s no doubt you’re getting what they’re telling you you’re getting,” he added.

PSE’s renewable energy program — one of a handful certified by Green-E, the country’s leading independent certifier of renewable energy — costs residential consumers between $4 and $10 extra each month.

At $10, the customer is essentially buying 100 percent green power — he or she is adding one mega-watt hour of energy, the average amount consumed by a family, to the grid. (Commercial users pay more, based on the amount of energy they use.)

But even green power is not completely “green,” some note. Nearly 80 percent of PSE’s green power comes from wind farms — giant turbines that have been criticized for killing birds, destroying habitat and creating eyesores in communities. The rest comes from biomass, low-impact hydro projects (where a river’s energy is harnessed without using a complete dam) and solar, PSE officials say.

But Harmon said that even wind power is improving and that the oft-cited criticism of wind power is “a red herring” that arose because of a couple of badly done projects.

“There are many, many very well-sited wind projects … that kill vastly fewer birds than downtown skyscrapers and vastly fewer birds than climate change will kill,” he said.

On Vashon, the Green Power program has taken off in just the last year or so, with a growing number of businesses, in particular, signing up, said Heather Mulligan, the market manager for PSE’s Green Power program.

Vashon College is another commercial customer that pays for 100 percent green power.

According to Tom Ban-gasser, who helped to found Vashon College, the energy costs of the two buildings owned by the college — Courthouse Square and the Sheffield Building — go towards the purchase of green power for PSE’s grid.

Gusto Girls is the only other Vashon restaurant that participates in the Green Power program; about half of the eatery’s electrical costs support PSE’s Green Power program, a PSE spokeswoman said.

Vashon’s residential and commercial participation is impressive, Mulligan said. All told, Islanders are on target to purchase enough mega-watt hours of renewable energy to power 305 houses for a year.

“There’s a very conscientious community on Vashon that has demonstrated a willingness to support renewables,” Mulligan said.

But just as important as purchasing renewable energy is lowering one’s consumption, PSE and other energy experts say.

And Sontgerath is hoping the additional costs she’ll face for her renewable energy at The Hardware Store — around $175 a month — will be almost completely offset by a number of conservation measures she and her staff are now taking.

When she decided to sign up for the Green Power program, she also had PSE undertake an energy audit of her restaurant, an establishment that — like most restaurants — uses a lot of power.

As a result, she said, her staff now unplugs appliances at night, turns off computers and keeps the lights off in the main dining room when only the bar is open.

“It’s not a sacrifice,” she said. “It’s just a change of habits.”

What’s more, the staff is encouraged by the changes they’re making, she said.

“I decided to jump in with both feet,” she said. “And it means something to my staff. They’re saying, ‘Wow, we’re making a difference.’”