For any grid based on intermittent power sources—which describes most renewable energy sources, such as wind and solar power—the ability to store excess energy for times when there is no wind or sun is crucial. Nanoptek’s technology efficiently converts excess power at any time of the day into hydrogen and stores it. “Then, by using a fuel cell, you can convert that hydrogen back to electricity in an on-demand way,” Guerra says.
It’s the first electrolyzer to be competitive with batteries and even provides some advantages. For example, unused alkaline batteries lose energy over time, whereas a cylinder of pressurized hydrogen gas will keep virtually indefinitely without losses. Batteries also lose energy to heat if power is drawn from them rapidly, which is not the case with hydrogen fuel cells. At telecommunication towers in remote parts of Africa or India, which are often powered by solar energy, batteries have performance issues due to the heat. “Our panels love heat,” Guerra says. “The hotter the electrolyte, the more efficient they get.”
Nanoptek envisions power plants for communication towers in the developing world scaled to also power microgrids for local communities, using the company’s technology to maintain a constant energy supply. “It’s a way to leapfrog an unreliable grid and deliver reliable, low-cost power to people in those parts of the world,” he says. “The R&D part for us is largely done, and the challenge now is to find funding to scale up manufacturing so the technology can be deployed and start positively impacting people’s lives.”
By the end of 2014, the company was taking its first orders and gearing up for production. For now, the technology is being marketed to businesses for large-scale operations. Companies whose trucks or forklifts run on hydrogen fuel cells generally have plenty of roof space for a set of Nanoptek’s photocatalytic panels to power their fleets, Guerra notes, adding, “There are also a lot of companies out there that use hydrogen in their manufacturing processes, and a lot of them are interested in having a cost-efficient way to make the hydrogen on site.”
The number of panels can be scaled up or down according to needs.
He points out that automakers and governments are beginning to turn their attention to hydrogen fuel cell vehicles, with car companies beginning to unveil their first hydrogen-powered production models and California building hydrogen filling stations. He hopes Nanoptek’s technology will prove integral to the new, hydrogen-based transportation infrastructure. “Our success depends on the success of other companies, but their success depends on a low-cost source of hydrogen, and that’s where we come in,” he says.
The systems are not yet economical or safe for residential use, as the compressor and dispenser required for home refueling are still too expensive for an individual homeowner, but Nanoptek envisions the first residential use being in planned developments where a cluster of homes could be outfitted with panels. Homeowners could chip in for a shared compressor and dispenser, using the system to power hydrogen cars.
Guerra also predicts the technology will one day circle back to the Space Agency that first funded it, where it will be used for planetary exploration. “Our devices, with sunlight and local water on an extraterrestrial body, will be used to make hydrogen fuel for rockets and oxygen for habitats,” he says. In fact, for each kilogram of hydrogen the system produces, it can make about eight kilograms of oxygen.
“It was really the NASA funding that financially got us off the ground and also established the validity of the technology,” he says. Whether that technology will one day get NASA rockets off the ground of extraterrestrial bodies remains to be seen.