Energy harvesting: ready for prime time?

Over the past 12 months, energy harvesting has undergone a rapid evolution from a mere theoretical technology to one supported by a healthy ecosystem of vendors with solutions that will be showing up in more applications, mostly in energy management and medical equipment, according to participants in a panel discussion at the nanoPower Forum.

"In the early stages of a high-tech market, you are going to be selling the sizzle. I would suggest that today we are selling the steak," said Jerry Ruddle, executive VP of Advanced Ceramics Inc., a vendor of flexible ceramic fibers and fiber composites for energy harvesting.

Energy harvesting uses piezoelectric, photovoltaic, thermoelectric and inductive devices to convert ambient energy—including solar, thermal and kinetic energy—into electrical energy. Panelists said energy harvesting technology is most promising for applications in medical devices and energy management in homes and commercial settings (such as a system of sensors that automatically turns off lights that aren't in use).

But panelists also acknowledged that the technology still faces a host of challenges, including the absence of standards, lack of participation by the large sensor vendors and skepticism or outright ignorance of the technology.

"There's still a sea of engineers out there that doesn't believe energy harvesting is real," said Tim Bradow, a VP at Infinite Power Solutions Inc., (IPS) a supplier of solid-state thin-film batteries. "It's real. It's here. You can have it today."

According to Regan Zane, an associate professor at the University of Colorado, people who learn of energy harvesting tend to want more from it than is realistic, such as the ability to generate the power needed to run a notebook computer or a blender. "It takes some realism and a different mode of thinking," Zane said.

Panelists suggested that as ultralow power designs become more popular, energy harvesting might one day provide sufficient juice to run a smart phone or other handheld consumer device. Today, though, applications are less ambitious and include things such as sensors and wireless light switches. (The most successful energy harvesting products to date are wireless light switches sold by vendors such as EnOcean GmbH, a spinoff of Siemens).

Mark Buccini, director of worldwide strategic marketing at Texas Instruments Inc., offered the most cautious view of any panelist about the applications for energy harvesting. Buccini and other panelists agreed that no matter how compelling the technology, it won't find critical mass unless it is economically viable.