DON'T worry, it's all uphill from here.
Japanese electronics giant Panasonic is making a £700 hybrid electric bicycle which will store power from freewheeling downhill in order to recharge a battery to help push the bike up again.
The bicycle is due to go on the Japanese market next mon
th and if, as expected, it is successful the company has said it will sell it in the UK.
In recent years, hybrid electric vehicles such as the Toyota Prius have become green icons because of their low fuel consumption and low greenhouse gas emissions. In particular they have become popular among Hollywood stars anxious to show off their environmental credentials.
The bicycle, called the Panasonic Vivi RX-10S, features a dynamo on the front wheel which transfers the energy generated by travelling downhill to a rechargeable battery near the rear wheel.
The bike includes a series of sensors which can work out when the cyclist is going uphill, or even just moving off from a standing start, so that the electric motor can kick in and help them move with a minimum of hard pedalling.
Although Panasonic is more famous in the UK for upmarket TVs, DVD players and stereos, in Japan the company is an established bicycle maker. The new hybrid bike will go on the market on August 20 in Japan, priced at £700.
A Panasonic UK spokeswoman said: "It will be a matter of seeing how it sells in Japan. If it sells well, then we will consider selling it here."
According to a leading expert on battery design, the breakthrough is mainly due to batteries becoming smaller, lighter and more powerful in recent years.
Peter Hall, professor of chemical engineering at Strathclyde University, said: "In principle, the idea is simple. When the bicycle is at the top of a hill, that is potential energy, and when it is moving downwards we have kinetic energy. Normally that kinetic energy is converted into heat from the friction of the brakes, but in this case it is used to power the battery.
"What they have done is very clever. Battery design has made huge progress in recent years. They have become smaller and lighter and much more powerful. I could see this being very popular here. The Prius proved to be much more popular than the makers expected."
The bike's motor features four different modes, from "high" for those feeling unfit and in need of a lot of extra push, to "off" for those wanting to feel the burn in their legs as they race home.
The motor will not help the cyclist to break the speed limit, however, as once the bike goes faster than 15mph, the motor will cut out and the biker must rely on momentum and muscle.
In addition, for those whose route to work will be so challenging that they cannot rely on a hill to give them extra power, the bike's battery can be topped up from the mains – it takes about five and a half hours to fully charge it up. The whole mechanism adds 2.5kg to the weight of the bicycle, and tests done by Panasonic on tracks which included a mixture of upward and downward hills have shown than the battery can power the bike for up to 113 miles without the cyclist having to stand up on the pedals to get the bike uphill.
Environmental campaigners have welcomed the new technology. Patrick Harvie, a Green member of the Scottish Parliament, said: "We need a transformation in our transport system, and while vanilla (normal] bikes are great for many people, many others will be interested in this innovative alternative. Anything that can help people to switch from the car to the bike is definitely a good idea."
The Toyota Prius relies on power generated by its petrol engine to recharge its battery and has become a green icon, despite criticism than some more conventionally designed cars actually have better fuel economy and lower emissions.
Some Prius owners have altered their cars to allow them to be charged up from an electric socket and Toyota plans to release a model which can be plugged in next year.
Last month, Scotland on Sunday revealed that sales of alternative-fuel, hybrid and electric cars had increased by 14% in the first four months of the year, compared with the same period in 2007, as drivers turned their backs on old-fashioned gas guzzlers.
The price of fuel in Scotland has risen from about 95p a litre last year to as much as £1.40.
The full article contains 768 words and appears in Scotland On Sunday newspaper.
