Revolve test drives the Honda FCX Clarity
The Honda FCX Clarity Fuel Cell Electric Vehicle (FCEV) was named 2009 World Green Car by 59 World Car jurors from 25 countries worldwide. BBC Top Gear's James May described it as "the most important car ever", and now - finally - Revolve gets to drive it, along with the Positive TV film crew at the Copenhagen Climate Change summit.
The ultimate electric vehicle?
The FCX is a fuel cell vehicle, with a hydrogen tank instead of a petrol tank. In the fuel cell, hydrogen is combined with atmospheric oxygen to generate electricity. The fuel cell is really a tiny electric power station, and generates its own electricity onboard rather than through a plug-in system.
Since the electricity required to power the vehicle’s motor is generated onboard using hydrogen and atmospheric oxygen, no CO2 or other pollutants are emitted in this process. It is the ultimate in clean performance – its only emission is the water produced as a by-product of electricity generation (H2 + O2 = H2O).
A compact and efficient lithium ion battery stores electricity generated during braking and deceleration in regenerative braking. The battery works in concert together with the fuel cell stack to power the vehicle.
If there aren’t any hydrogen stations, how will I fill up?
Honda is working on other interesting projects to supply vehicles with hydrogen. The Home Energy Station is one idea – a system installed in your house that provides electricity for the home and converts natural gas to hydrogen to power a fuel cell car. Another is the solar refuelling station, which uses solar power to extract hydrogen from water.
Where does the hydrogen come from? And is there an environmental cost?
Ah, the question on everyone’s lips! Hydrogen can be produced from renewable sources such as solar, wind or hydroelectric power (using electrolysis to extract hydrogen from water). Certain production methods are better suited in different areas of the world, but nevertheless it is possible to achieve a stable supply of hydrogen from renewable energy sources.
Currently, the most common way of producing hydrogen is steam reforming from natural gas. There is an environmental cost of extracting hydrogen in this way, but it is the most widely available approach.
It’s worth asking the same question of battery electric vehicles. There is clearly an environmental cost of a BEV running on electricity made from a coal-fired power station (the way most of the UK’s electricity is produced at present).
Are cars with hydrogen tanks safe?
Honda’s FCX Clarity is in public use in America and Japan already, and therefore it had to go through the same stringent crash and safety tests as any other road-going car. As well as protecting occupants from front, side and rear impact, the Clarity also features a special impact-absorbing framework around the fuel cell system and high-pressure hydrogen tanks, to shield them during a collision.
At the moment you can’t buy an FCX Clarity outright. However, in the United States, Honda is leasing cars to customers (from celebrities to Joe Public) for $600 a month (around £380). Customers follow a three-year lease term, which includes maintenance and collision insurance.
See more World Car finalists and award winners from our Eco-Rallies
