By PETER SUR
Tribune-Herald staff writer
Islanders could be riding on a hydrogen fuel cell-powered Hele-On shuttle bus by the end of this year, or early 2013.
Two other buses are headed to Hawaii Volcanoes National Park for carbon emissions-free tours within the park, according to people associated with the pilot project.
The Hawaii Natural Energy Institute, a research arm of the University of Hawaii, is spearheading the project with about $5 million in funds from a variety of sources, including the U.S. Department of Energy, the Office of Naval Research, and the state’s hydrogen fund and fuel taxes. Hawaii County’s only expense will be to provide a driver for the bus.
HNEI will use this money to build a small electrolyzer-based hydrogen production system at Puna Geothermal Venture and two filling stations — one at the county’s Mass Transit Agency baseyard in Hilo and one at the national park. Hydrogen produced at PGV in lower Puna will be compressed into 130-pound loads and driven to the filling stations in trailers that meet federal safety standards.
Hydrogen is the most abundant element in the universe, but on Earth it’s bound up with other elements. Electrolysis is the process of running an electrical current through regular water to separate it into oxygen and hydrogen. PGV will provide the electricity.
UH-Hilo’s Pacific Aquaculture and Coastal Resources Center has expressed interest in using the oxygen to support its fish farms. The hydrogen will be compressed and driven to the filling stations.
Ron Terry of Geometrician Associates said the draft environmental assessment that his firm is producing will be released in August for public comment.
“It’s sort of a demonstration project of how hydrogen can be produced and used as a grid management tool,” Terry said.
Hawaii’s renewable energy portfolio includes some resources with fickle power supplies, and the electrolyzer can stabilize it. For example, if the grid became overloaded on a sunny day by homeowners’ photovoltaic systems, the electrolyzer could power up rapidly to soak up that excess energy. On the other hand, if renewable energy input suddenly dropped, the electrolyzer could power down to keep more electricity flowing into the grid.
“The electrolyzer acts as a variable load that can ramp up and down very quickly,” said Mitch Ewan, HNEI’s hydrogen systems program manager.
The system will be tested to see whether it can ramp up and down as quickly as would be needed, and to see whether it can continue to do so at a predictable level over the two-year span of the pilot program. It will not be hooked up to the power grid without further studies and approval of Hawaii Electric Light Co., Ewan said.
The energy content in a kilogram of hydrogen is roughly equal to a gallon of gas, Ewan said. “The most we can generate is (the equivalent of) 65 gallons of gasoline a day. That’s pretty small.”
HNEI is giving Hawaii County the money to buy a 19-passenger ElDorado shuttle bus and to swap out its internal combustion engine for a hydrogen fuel cell. These buses will have a 30 kg-capacity tank and a range of 150 to 180 miles, Ewan said, depending on the terrain of the bus route. They will also run silent and be about twice as efficient as a normal diesel bus. Energy-regenerative braking will help to increase the efficiency of the buses, Ewan said.
The conversion of the buses will be done by the Hawaii Center for Advanced Transportation Technologies, which is managed by the High Technology Development Corp., which is attached to the state Department of Business, Economic Development and Tourism.
HCATT has been working with the U.S. military in recent years to develop fuel cell vehicles and infrastructure, but the partnership with Hawaii County will be the first time in Hawaii that the system is being installed on non-federal land, Ewan said.
Representatives from the Mass Transit Agency and Puna Geothermal Venture were unavailable for comment.
A hydrogen bus project has been in the works for years. Mayor Billy Kenoi hinted at it in late 2009, and in May 2011 Mass Transit administrator Tom Brown said the buses could appear by the end of that year.
“We’re trying to have it up and running by the end of this year,” Ewan said.
Email Peter Sur at email@example.com.