E-bikes take off

Electrically powered bicycles have become very popular in continental Europe, but could they find a willing market in the UK? E&T finds out.

Electric bicycles are by no means a new phenomenon. When pedal cycles were invented in the 19th century, engineers were experimenting by adding various motorised engines such as the internal combustion engine versions spawning the first motorcycles. As this was the age of steam, naturally many Victorian inventors dared to experiment with steam-power.

There were also various patents for electric-powered pedal cycles. But, as Victorian commuters were not facing an energy crisis, speed cameras, congestion charges, road tax, petrol duties, parking fines and even a driving licence was not necessary (the first driving licences were issued in the UK in 1903).

Needless to say, the only green issues which drivers and passengers faced would have been the unfortunate complexion that resulted from a journey on one of these early contraptions - occasionally followed by vomiting.

In fact, pedal-assisted electric bicycles (e-bikes) were only acknowledged under UK law in 1983 which exempted these types of bicycle from needing to be taxed and insured for road use if the maximum speed was no more than 15mph (24km/h). The 1983 regulations also put restrictions on the weight (40kg including the battery) and said that no-one under the age of 14 could ride one on the road.

Electric bikes gaining popularity

Across the board, cycling is becoming more popular in many parts of the world. This can be explained, in part, as many consumers turn away from more expensive and environmentally 'unfriendly' transportation methods such as cars.

But reports suggest that the growth of e-bikes is particularly strong. They are gaining favour in the Netherlands with the other main electric bike market in Europe being Germany - but in general, Europe is experiencing massive growth.

According to the Dutch transportation industry organisations RAI and BOVAG, 140,000 e-bikes were sold in Holland in 2008, while in Germany sales totalled 100,000 units. Germany's bicycle manufacturer's trade body ZIV says that sales are expected to be 30 per cent higher for 2009.

Unfortunately, precise numbers for other European markets are not readily available but, if the manufacturers and retailers are to be believed, sales are experiencing a significant upsurge all over Europe.

Having said that, Europe has a fair way to go. China, the world's biggest bicycle market, sold 21 million e-bikes in 2008 - according to the China Bicycle Association (CBA). Of these, 580,000 were sold abroad. This figure is also expected to rise sharply.

How does it work?

So how exactly does an e-bike work? This is not as foolish a question as you might think. There have been some interesting advances in materials science and battery technology that now make electric bicycles more practical than in previous years. Much of this has come from the computer industry.

For example, battery technology has advanced a great deal. Three factors are important when choosing the right battery: weight, how long the battery lasts, and how long it takes to recharge. Lithium-ion batteries appear to fit the bill.

These are very common in consumer electronic devices, especially the portable type. The qualities that make them ideal in consumer electronics also make them ideal for bicycles. For example, they have one of the best energy-to-weight ratios of any battery type and recharging them is straightforward. Additionally, they do not suffer from 'memory effect' - which is when a battery that is only partially discharged is subsequently recharged but never regains its full capacity again. Furthermore, the charge lost over time when not in use is negligible.

But lithium-ion batteries do have certain drawbacks. For one, the shelf life is limited in comparison to nickel cadmium batteries. From time of manufacturing, regardless of the number of charge and discharge cycles, the battery's capacity will decline. Furthermore, they are less efficient in high drain applications (a factor of e-bikes). Rising internal resistance can cause the voltage at the terminals to drop under load, reducing the maximum current that can be drawn from them.

Other issues relate to safety concerns and news reports of laptop batteries, in particular, combusting, although in these cases the actual manufacturing of the batteries was at fault. Overall, 1 per cent of all lithium-ion batteries are recalled.

Alternative power sources, such as fuel cells, have not as yet been commercially successful. However, there are a great deal of advances in lithium batteries to increase their capacity, shelf life, power output and recharge times.

Latest technology

For example, Toshiba has invested heavily in SCiBs (super charge ion battery). SCiBs charge more quickly than lithium-ion and are supposed to retain their charge for longer. They were first sold in April and are being used on models such as US-based Schwinn Bicycle Company's Tailwind bicycle. The company claims that it will fully recharge in 30 minutes, compared with a normal charging time of four hours for general electric bicycles.

E-bikes have also benefitted from advances in conventional pedal cycle technology. Materials such as titanium and carbon fibre are very common on e-bikes to keep the weight down. Combined brake and gear systems are also widely used. These types of technology have been incorporated into the GoCycle bicycle, developed by ex-McLaren Formula One engineer Richard Thorpe.

The GoCycle, manufactured by Karbon Kinetics, also uses an injection-moulding process used more commonly used in plastics found in consumer tech hardware. Thixomoulding is where pellets of metal are heated in a barrel until almost molten before being injected into the mould cavity. The process is used with lightweight magnesium alloy to produce very strong structures.

Ultra Motor

UK-based Ultra Motor's A2B bicycle recently went on sale in the UK.

The A2B is a pedal bike with an electric motor which has a 'rocket boost' button. The makers claim that it does not require a licence.

The company produces two versions: the A2B Metro and the A2B Hybrid, each with a price tag of almost £2,000. Batteries run for up to 20 miles and are charged using a mains plug.

Ultra Motor president and co-founder Joe Bowman says: "We can't flatten hills or remove tailwinds, but we can give riders the next best thing with power-assisted bikes. The technology has now progressed to make it more commercially viable."

Laws and safety standards

However, the laws relating to the definition of electric bikes are soon to change in the UK and Europe as the European Union (EU) seeks to harmonise the legislation of bikes across the supranational territory.

A new safety standard, EN 15194, has recently been published and all EU countries have to implement this new standard by 31 July 2009. It contains several new prerequisites for e-bikes which cover adjustments to weight and voltage limitations.

The maximum power allowed will be 250W (compared with 200W under the current UK standard), with a maximum assisted speed of 25 km/h (similar to the current UK speed restrictions).

Generally, the new regulations are welcomed by the industry as it will allow one type of bike made for one EU country in particular to also be certified for all other EU countries. However, there is confusion as to whether companies will be allowed to self-certify or would have to put their bikes up for independent testing.

This is crucial as those who choose to self-certify their own bikes may interpret the regulations differently to other manufacturers. For example, UltraMotor's A2B has a 'boost' button that ramps up the speed to 20mph for 'off-road' use.

Critics of independent testing point to the high costs involved which could deter many companies from entering the European market.

Clearly, the industry still has to dot the 'i's and cross the 't's to ensure that there is full understanding of the new regulations, however well intentioned its implementation may be.

Though common on some parts of the continent, in the UK it is still rare to see an electric pedal cycle on the road.

For it to really take-off and become less of a rarity, it will have to accept light-touch regulation where safety is concerned without increasing the running cost to riders.

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