Attendees of Monday’s Tech Pau Hana got a glimpse of off-the-grid living at Puu Waawaa Ranch, as well as a look at a test of hydrogen fuel cells in action.
Blue Planet Research, which has a laboratory at the ranch, hosted the monthly technology gathering, with Director Paul Ponthieux giving the tour and explaining what the organization has been working on here on Hawaii Island.
“One of our primary focuses here is energy storage,” Ponthieux said. “That’s what we study.”
The lab and 32-acre ranch are solar powered, Ponthieux said. Blue Planet Research first ran a two-year test with the Hawaii Natural Energy Institute at the University of Hawaii, checking seven different kinds of solar panels. Data indicated the ranch should get about five hours of sunlight a day, but it actually averages less, closer to 3.8 hours. That led Blue Planet Research to install a larger-than-usual solar array, 85 kilowatts worth on the lab’s large, slanted roof, to ensure they would capture enough sunlight.
So far they have, Ponthieux said. The light-generated power is stored in several kinds of batteries, including a vanadium-redox flow battery, the only one of its kind in the state. This system is scalable, allowing Blue Planet Research to adjust the size for any type of application.
It has energy efficiency in the mid-70s, which means about 70 percent of the energy that goes into the battery is able to be recaptured. That’s an OK level, Ponthieux said.
Inside the lab, another type of battery sits inside a tall, black cabinet. If the setup looks a bit like a stereo system, that’s because it’s made by stereo manufacturer Sony, Ponthieux said. This one is a lithium iron phosphate battery, which uses olivine — the same material that makes sand green.
A few things make this type of battery superior to a lithium ion battery. For one, it’s a more stable power source. Two, it doesn’t heat up nearly as much as lithium ion.
“The other really phenomenal thing is it goes 0 to 100 percent in 90 minutes if you give (it) full current,” Ponthieux said. The vanadium-redox flow battery needs five to six hours.
The quick charge is good for areas such as Puu Waawaa Ranch, where the solar window is fairly short each day. The Mars habitat project on Mauna Loa is also using a lithium iron phosphate battery, with a lot of success so far, Ponthieux said.
Ponthieux also explained how the company is testing hydrogen as a way to store energy, fuel vehicles, including a forklift on the property, and even be used in cooking. He said he’s in the process of refitting a gas stove to run on hydrogen and showed what a hydrogen-fueled wok burner looks like.
Because hydrogen is lighter than air, the gas shoots straight up when released. That means if it does catch fire, it burns in one direction. The risk of catching another tank of hydrogen, or nearby buildings, on fire is fairly low, Ponthieux said.
“We use hydrogen as a back up to the batteries,” he said. “Hydrogen is not the most efficient round-trip energy storage.”
But it does offer a multitude of ways it can be used, he added.
Blue Planet Research has been working with the U.S. Department of Energy and major auto manufacturers to bring cars with hydrogen fuel cells to Hawaii Island. Hawaii County could have several retrofitted hydrogen buses by next year.
A similar test in California would require more than 60 hydrogen fueling stations, and cars would be limited to driving within a certain distance of those stations, Ponthieux said.
“We need five stations around the Big Island for mobility,” he said. “It’s complete mobility,” meaning the drivers would be able to go anywhere on the island and still be within driving distance of a refueling site.
Planned sites are at the Natural Energy Laboratory of Hawaii Authority in Kona and somewhere in Ka‘u, Ponthieux said. Other sites are still being discussed.
In addition to fueling cars, hydrogen will soon power baggage towing carts at the island’s airports, he added.