Honda FCX Clarity and Home Hydrogen Fueling Stations

Honda's decision to transition its FCX Clarity into limited production and lease some 50 of these hydrogen fuel cell cars to customers in Southern California is a groundbreaking move. Why Southern California? A small number of very expensive hydrogen fueling stations already exist here and more are in the planning stages. In tandem with this, Honda has also shown a longer term solution for refueling hydrogen vehicles in the form of its fourth generation Home Energy Station. Working with its technology partner Plug Power, Honda debuted the first Home Energy Station in 2003, followed by improved and more compact HES II and III versions in the years that followed.

The Home Energy Station is a self-contained unit that not only supplies the high purity hydrogen required for a fuel cell vehicle, but through co-generation also heats a home, provides hot water, and produces electricity. Its energy feedstock is the natural gas that's already supplied to most U.S. homes. In operation, a fuel processor uses steam reformation to convert natural gas to hydrogen gas. Then, after purification and compression to a higher pressure to allow more compact storage, the hydrogen is stored in tanks and available for refueling a hydrogen vehicle's 5,000 psi on-board storage cylinders.

The HES also has its own fuel cell that uses hydrogen to produce electricity for the home. An inverter converts this fuel cell's DC output to standard 120 volt AC household electrical power. Waste heat from the fuel cell is used for home and water heating. The latest HES IV version is about 70 percent smaller than the first HES design, making it more suitable for household installation. Size reduction was achieved by combining the unit's gas purification and power generation components. This also increased overall efficiency while making it easier to switch from hydrogen production to power generation as needed.

Don't expect to see the HES on the market soon. Honda says it's unlikely to be ready for home use before the middle of the next decade at the earliest. However, Honda is already proving out its HES IV at the Honda R&D Americas facility in Torrance, Calif. and other demonstrations are likely.

Is this the ultimate enabler for environmental vehicles? At present the HES IV does use fossil fuel since it operates on natural gas, although this is one fuel that's found in abundance in the U.S. and North America. Also, it produces carbon dioxide and nitrogen emissions. Still, Honda's Stephen Ellis shares that using this system to generate hydrogen and fuel an FCX Clarity can reduce total well-to-wheel CO2 emissions by 60 percent compared to an equivalent gasoline-fueled car. Overall, the HES IV can reduce CO2 emissions by an estimated 30 percent and energy costs by an estimated 50 percent compared to the average U.S. home with grid-supplied electricity and a gasoline-powered car.

Separately, Honda is developing solar-powered hydrogen refueling stations that would use no fossil fuels or produce any CO2 gases, or any other emissions for that matter. Honda is now operating an experimental solar-powered hydrogen station at its facility in Torrance. The station uses Honda's water electrolyzing module to produce hydrogen using next-generation thin film solar cells developed by Honda Engineering. The thin film, made from a compound of copper, indium, gallium, and selenium, allows production of high pressure hydrogen at 52 to 66 percent efficiency.