The bicycle is one of the most efficient means of locomotion there is. Compared with other mechanical vehicles, it delivers high performance for low input. Using the same effort as walking, it covers three times the distance. The energy required to move with a bicycle is renewable and far from consuming natural resources contributes when used in moderation to the health of the user; it is also the quietest of all vehicles.

A substantial increase in urban bicycle use would increase the quality of life of everybody: there would be less noise, atmospheric pollution and traffic congestion, and fewer parking problems. It would be a great contribution to individual and public health. An ideal solution.

Ih that case, why don't  we adopt it?

There are different reasons, among which the comfort and convenience of the car are primamy, but this convenience is only relative. Juge numbers of motorcycles demonstrate that two wheels have great advantages over four when traffic is heavy, namely speed, manoeuvrability and easy parking.

The bicycle can lay claim to all these advantages (it is often quicker then a car in cities) but it has a few limitations as to speed, workable range and journeys with steep gradients. But these difficulties are no longer a problem with a new class of vehicle, wich in some couries such as Japan and Switzerland is being used increasingly with considerable success: the electric bicycle.

It shouldn't be confused with another vehicle wich is also currently being developed, namely the electric motorcycle. there are marked differences. An electric motorbike is more or less a conventional motorcycle, the only variation being the motor; but an electric bicycle is, basically, a bicycle designed so that the muscular effort made by the cyclist is optimised, while that effort remains the main energy input. Its electric motor merely adds energy to what the rider already produces.

The process is identical to that of a conventional push-bike, but a computer is in charge of the motor. For this reason the electric bicycle has sensors that continually monitor the speed of pedalling and the work rate of the cyclist. When there is no great hurry, or on flat or downhill stretches, it is perfectly possible to ride with the motor disconnected, but when in use it will add, in no case, more than 50% to the rider's own energy input.

This can seem insignificant, but experience has shown that this combination of two energy sources, muscular and electric, can deliver average speeds of about 22 miles per hour, can clib gradients of more than 20%, with an operational range of over 20 miles rising up to 60 miles in the case of a trained cyclist - much further than an electric motorcycle.

With an electric bicycle we can make longer journeys than with a push-bike and at greater speed. Steep slopes are no longer an obstacle and night riding is safer because the cycles's halogen lamps are fed directly from the battery and remain alight when the vehicle is stationary. In winter the cyclist remains warm from his own exertions, unlike the motorcyclist, and these same exertions are good for his health. He can use mudguards, obviating the need for protective clothing, and panniers for work or shopping needs.

Thus an electric bicycle requires physical work as does a normal bike; but these modifications bring its level of usefulness close to that of a motorbike, allowing us to undertake journeys which would be too long or too hard on a normal push-bike. The need to contribute pedal power also adds to the operational range, and gives another important plus over other motor vehicles. When the battery or other energy source runs out, one can cantinue on pedal power alone, albeit with a slight increase in effort.

There are all sorts of different electrical bicycles, ranging from simple kits wich upgrade an ordinary push-bike using power transmission via friction on a tyre, to highly developed state-of-the-art models. The strong currencies of the countries where they are manufactured renders the prices of these models relatively high, but the user benefits are not negligible: a unit cost of 0.12 euros per hundred kilometers with clear and inmediate benefit to health and well-being; also the environmental and social benefits of a silent, nonpolluting vehicle.

It would be wise to choose one of the best models, given the usefulness of this product to both individual and society (if the political will exists). Here some examples:

• Flyer
• Dolphin velocity
• Heinzmann Estelle
• Yamaha PAS XPC 26
• Aprilia
• http://www.currietech.com
• http://www.evglobal.com
• Altres

The status of electric bicycles within the law varies, and in some countries they find themselves in a legal limbo.

In principle it can be said that if the motor cuts out at 24 kph (14.9 mph) and that the vehicle only moves when actively pedalled, as in the case of the three models shown above, the vehicle can to all purposes be considered a push-bike an can be used on the public highway without further ado.

However, in the Flyer 2000 range there are more powerful models wich reach higher speeds. These are currently registered only in Switzerland, where they come into a special category, and require matriculation with a car drivin licence: there are not subject to speed limits and no crash helmets need be worn. In some Cantons they are tax-free or even subsidised - and thus these vehicles are already forming part of daily life in that country.

In the spanish state there are no special regulations, and we may suppose that the principle of user propulsion will apply, and these will be treated as bicycles throughout Europe as is already the case in France and Germany. Surely the regulations currently under debate in Europe will set the standard for the inmediate future.

Althought less, an electric bike also consumes electrical energy.  If we want that their use is absolutely sustainable, we must watch that energy used for their operation is not of fossil nor nuclear origin.  Although at individual level the consumption is minimum, a masification could cause problems by those is desirable that, whenever it is possible, energy that we spend comes from a clean source, like for example photovoltaic.  A single panel of 110 watt connector by means of an adapter to the electrical network will produce an greater amount of energy daily to which can spend an electric bike, the excess of production returns to the network thus diminishing our domestic consumption.  In case we do not have any connected apparatus, we will be able to even observe like the accountant turns the other way around.  You can see the statistics of a concret case clicking here.