While many new plug-ins boast the convenience and simplicity of recharging the car battery from a household wall socket, how many vehicles can claim to provide the opposite?Honda has installed an inverter in the trunk of one special FCX Clarity hydrogen fuel-cell vehicle, providing output power that could supply up to 8 kilowatts of electricity for more than seven hours from a full tank of hydrogen — a figure that is supposedly enough to power the average Japanese home for six days. This particular FCX has been delivered to the Saitama Prefecture government, which was also an early-adopter of a solar-powered hydrogen station.
Concerns over power shortages have heightened since last year’s natural disaster and the subsequent nuclear plant shutdown, causing a spike in interest for electric vehicles that may double as emergency power suppliers for homes. Last year, Nissan demonstrated its Leaf-to-Home, which claimed the power output could generate enough to sustain an average household for two days. Unlike fuel cells, an electric battery can only store electricity rather than generate it, resulting in a less flexible application when compared to fuel-cell technology.
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http://www.autoguide.com/auto-news/2012/03/honda-fcx-clarity-fuel-cell-powers-japanese-house-for-six-days.html