(BIVN) – Hydrogen-powered vehicles are on the way to Hawaiʻi Island.

On June 18, the Hawaiʻi County Council Committee on Public Works and Mass Transit was given a presentation by the Department of Research and Development regarding plans to utilize electric and/or hydrogen buses.

Puna Councilmember Matt Kanealiʻi-Kleinfelder, who requested the update, said he would like to see the emerging technology deployed as a step towards a cleaner, greener and sustainable island society.

“We started this project here for the Big Island almost ten years ago,” said Mitch Ewan, Hydrogen Systems Program Manager for the Hawaiʻi Natural Energy Institute. “We’re now at NELHA. We’re maybe weeks away from our hydrogen station actually coming online. Our first bus is over on Oʻahu, just going through its final commissioning. It’s a 29 passenger, fuel-cell hybrid bus. Brand new. Looks awesome. So, as soon as my hydrogen station is up and running, we’ll bring the bus over here and then we’ll do final commissioning with some of our contractors, just making sure all our software and communications equipment is working. So, we’re basically ready to go.”

Riley Saito, the Energy Specialist for the Hawaiʻi County Department of Research and Development, gave the presentation on Hele-On Zero Emission Buses, or “ZEBs”.

Saito first talked about pilot Battery Electric Bus (BEB) project, which in December 2018 concluded that BEBs would best be deployed on shorter routes, and that island topology is a major factor on the life of the battery. The County is slated to get 3 Battery Electric Buses in early 2021.

Then, Saito switched his talk to Hydrogen Buses, which have a much longer range (200 miles) and are ideal for the Big Island’s topography and long distances.

He noted that the Hawaiʻi Natural Energy Institute has provided a federal grant for one hydrogen bus, and in addition, Hawaiʻi Volcanoes National Park plans to redirect two hydrogen buses to the County. There is also the potential to convert the Hele-On gas-fired fleet to hydrogen.

In a direct comparison, Saito showed how effort and cost for operating a fleet of Battery Electric Buses increases as the fleet size grows, while it inversely decreases for a growing fleet of hydrogen buses.

In addition to the hydrogen station at NELHA in Kona, officials are currently identifying a location at the Hilo Baseyard for a 2nd hydrogen station.

According to a list of hydrogen facts & safety considerations found via the Hawaiʻi County Research & Development website:

Hydrogen gas (H2) is a colorless, odorless and tasteless gas. It is non-toxic but can displace oxygen, acting as an asphyxiant if confined.

Hydrogen gas is 14 times lighter than air and rises twice as fast as helium and 6 times faster than natural gas at a speed of almost 45 mph (65.6 ft./s). Therefore, unless it is contained, the laws of physics prevent hydrogen from lingering near a leak (or near people using hydrogen-fueled equipment).

Hydrogen leaks present a risk of fire when mixed with air. However, the small molecule size results in very high buoyancy and diffusivity, so leaked hydrogen rises and dilutes quickly in open air.

Hydrogen flames burn at a high temperature, but have a low radiant heat. Hydrogen flames are nearly invisible in daylight, but can be indirectly visible by way of emanating “heat ripples”.

The only product of hydrogen combustion is water so there is no smoke or soot.

Hydrogen has a wide range of flammability concentrations between 4% and 74%. It ignites more easily than any other common gas and a high-pressure leak can even ignite spontaneously. The best way to extinguish a hydrogen fire is by stopping the flow of gas.

Hydrogen has the highest combustion energy per unit weight of any combustible fuel.

Hydrogen can be combusted or used in a fuel cell to produce energy, but fuel cells are more efficient. 1 kg of Hydrogen has the energy content of approximately 39 kWh of electricity

1 bar = 1 atmosphere (atm) = 101.3 kPa = 14.7 psi

1 kWh ≈ 3.6 MJ

For more information on hydrogen as an energy source, visit this website.

Councilmember Kanealiʻi-Kleinfelder says he plans to bring forward legislation in the coming weeks to further foster this “sustainable resource, economic development tool, transportation transition and decarbonization of county and personal vehicles”.