Governors' Wind Energy Coalition

SAN FRANCISCO — Cory Skky, a VIP host at Temple Nightclub, strained to hear over the thumping beat. “Piezoelectric dance floor?” he shouted. “We don’t have one.”

Those who come here seeking the energy-generating dance floor are several years too late. The nascent technology proved too clunky and unpopular with club patrons.

The floor panels, which moved up and down in order to absorb the energy of dancers, were 10 inches higher than the regular dance floor.

“You’d have to step up on it. That was always kind of a liability,” said general manager Benjamin Tom. “It was something that we could just show people what the future was.”

Piezoelectricity — in which materials generate energy when compressed — may still be the future. At least that’s what some Californians believe. A new $2 million subsidy from the California Energy Commission will fund pilot projects exploring the use of piezoelectricity, with the eventual goal of installing generators under roadways and railways to capture the energy of vehicles passing over them. Supporters say it could revolutionize both roads and renewable generation, but others caution that the technology isn’t likely to pan out. It’s commonly used in small-scale applications like sound equipment and ignition systems for gas stoves, but has yet to take off on a larger scale.

The state says it could be considered renewable energy, even though it mostly originates with fossil fuels at the moment, because the source is theoretically inexhaustible.

State Assemblyman Mike Gatto (D), chairman of the Assembly Utilities and Commerce Committee and a candidate for state treasurer in the 2018 election, introduced a bill five years ago to promote piezoelectricity. He became a convert to the technology after a friend waxed enthusiastic about a road he saw in Israel, and described it as the next frontier in road building. He cited estimates that a 10-mile stretch of four-lane highway could power a city of 100,000 people.

“I’d like to go down in history as the father of this technology,” he said. “A few decades ago, solar was dismissed as hippie, utopian, ‘Oh, you’re going to stick black silicon in the desert and it’s going to generate energy.’ We’re sort of at that ‘Yeah, right,’ moment for this, but I think we need to change attitudes.”

While the concept is risky, it’s a good example of the type of project that California policymakers are in the business of funding, one energy expert said.

“It seems to be the kind of thing you’d want the CEC to do,” said Eric Gimon, a senior fellow with Energy Innovation, a think tank specializing in climate change and clean technology. “It’s not completely crazy, but no sane investor would touch it, so let’s go take a look; let’s see if it’s got promise.”

Michael Gravely, deputy chief for energy research and development at the CEC, which is holding an informational workshop for applicants tomorrow, said the technology could benefit the state’s overall clean energy targets.

“If this thing works, it could potentially be certified as a renewable technology and help us meet our 50 percent renewable goal,” he said.

Yet Temple’s dance floor — which Gatto referred to in a recent press release touting technology — provides an unwitting example of how far piezoelectricity still has to go. Gatto also cited a piezoelectric installation at an East Japan Railway Co. station in Tokyo. That project garnered mentions in the company’s corporate sustainability reports from 2008 to 2010 before dropping off the radar.

The assemblyman conceded that such projects can be viewed as gimmicks.

“I was not that thrilled by the Japan railway or the San Francisco nightclub,” Gatto said. “That’s sort of showy and a token; you dance on the floor and the lights go on.”

The club’s floor, made by Netherlands-based Energy Floors, isn’t actually piezoelectric, either. It’s electromechanical, relying on small up-and-down movements to turn a generator. The company thinks its technology might be better-suited to roadways than piezoelectricity, which uses specific materials, like quartz and ceramics, that by their physical properties actually generate electricity when compressed.

“Based on our calculations for roads in the Netherlands and Brazil (we have a partner there) a payback period of 10 to 12 years is realistic,” said Energy Floors spokeswoman Sylvia Meijer-Villafane. “Piezo would not be interesting under a road at all, because of the low energy efficiency.” The company demonstrated cars driving over the floor tiles in 2014.

The press release also claimed Temple “piloted the technology under their dance floor to run their lighting,” which was never the case, Tom said. Rather, the nightclub used it to run a display that showed how much power was being generated.

“The amount of energy it produces is just so small,” he said, and Temple has more than 10,000 lightbulbs.

At Gatto’s request, the CEC conducted an initial study in 2014 that found cost estimates for piezoelectricity were all over the map. It estimated the cost at $80 to $200 per megawatt-hour — comparable to natural gas at the lower end and offshore wind at the higher end, according to statistics from the U.S. Energy Information Administration.

Temple’s floor cost $50,000, but the club isn’t a penny-pincher. It has also attempted a sustainable sushi restaurant, as well as a rooftop-mounted wind turbine, but neither was workable.

Once the pilot projects establish better cost estimates, the CEC will consider doing a larger test on an actual road to figure out how infrastructure and cars would be affected. One suitable location could be a section of Interstate 10 in Southern California that the California Department of Transportation uses for testing purposes.

The $2 million is coming from a charge on customers of the state’s three biggest electric utilities, which goes toward projects that have the potential to improve reliability, lower costs or increase safety. The program gives out $115 million per year on average. Some grants require applicants to come up with matching funds, but piezoelectricity is so early-stage that the agency doesn’t think projects will be able to provide their own funding.

“If we do that, it’s very likely to push away some of the people we’d like to encourage,” Gravely said. The CEC knows of roughly a half-dozen companies that might apply, one of them in-state.