Honda has begun work on a smaller solar hydrogen station prototype intended for use as a home refueling appliance. Capable of an overnight refill of fuel cell electric vehicles it is designed to be a single, integrated unit that will fit in the user's garage. Honda's next generation Solar Hydrogen Station, though not as big as the previous systems, will still produce enough hydrogen (0.5kg) via an eight-hour overnight fill for daily commuting (10,000 miles per year) for a fuel cell electric vehicle.

The company says its previous solar hydrogen station system required a bulky electrolyzer and a separate compressor unit to create high pressure hydrogen. The compressor was the largest and most expensive component and reduced system efficiency. By creating a new high differential pressure electrolyzer, Honda engineers have been able to eliminate the compressor entirely - a world's first for a home use system. This innovation also reduces the size of other key components to make the new station the world's most compact system, while improving system efficiency by more than 25 percent (value calculated based on simulations) compared to the solar hydrogen station system it replaces.

This will make the unit much more palatable for motorists with smaller-sized garages or apartment dwellers with shared parking facilities.

Designed to work in conjunction with Honda's FCX Clarity vehicle, the charging station is also compatible with a "Smart Grid" energy system. Honda says its Solar Hydrogen Station would enable users to refill their vehicle overnight without the requirement of hydrogen storage, which would lower CO2 emissions by using less expensive off-peak electrical power. Honda says that during daytime peak power times, the Solar Hydrogen Station can export renewable electricity to the grid, providing a cost benefit to the customer, while remaining energy neutral.

Engineered for an eight-hour, slow fill for overnight refilling of a fuel cell electric vehicle, the home-use Solar Hydrogen Station would replenish the hydrogen for a typical daily driving, meeting the commuting requirements of many drivers. As with the previous generation system, Honda says the hydrogen purity from the new station meets the highest SAE (J2719) and ISO (14687) specifications.

Solar power

Installed at the Los Angeles Center of Honda R&D Americas, the new Solar Hydrogen Station will employ the identical Honda Soltec 48-panel, 6.0kW solar array that powered the previous system. The array utilizes thin film solar cells composed of copper, indium, gallium and selenium (CIGS).

A key strategy in Honda’s creation of a solar hydrogen station for home-use was to create a new lifestyle with convenient, clean, energy-efficient and sustainable home refueling, by addressing the need for refueling infrastructure that can advance the wider use of fuel cell electric vehicles by consumers.

Honda hopes the combination of a fuel cell electric vehicle and the solar hydrogen station will help lead to the establishment of a hydrogen society based on renewable energy, resulting in a major reduction of CO2 emissions and greater energy sustainability. No word yet on a testing schedule or availability.

Historically speaking …

Honda began operation of its first Solar Hydrogen Station at the Los Angeles Center of Honda R&D Americas in 2001 with the creation of the three-unit system with hydrogen storage in July.

By October that year, Honda was working on a new two-unit system with an original Honda electrolyzer and a new solar array utilizing prototype Honda CIGS solar cells that offered improved system efficiency.

In August 2008, a solar array fitted with mass production CIGS cells from Honda Soltec Co., reduced the size of the array by 20 percent and further improved photo voltaic (PV) energy efficiency.

Now, a new single-unit station begins operation, improving to world's best system efficiency - increasing the efficiency by more than 25 percent (value calculated based on simulations) compared to the previous solar hydrogen station system, for a world's highest system efficiency.

The current research is taking place at the Los Angeles Center of Honda R&D Americas, Inc.