Slimline tonic

Early next month film star George Clooney will take delivery of a new high-performance car with sporting pretensions. The $85,000 (£45,000) carbon-fibre two-seater is capable of doing 0-60 in four seconds, and has over 1,000ft-lb of torque at its disposal.

Clooney is believed to want to use the car, built by UK automotive technology and motorsport specialist Prodrive for US firm Commuter Cars, for daily trips between his home and the set of his latest movie.

But surely there's nothing particularly unusual in a Hollywood star buying a sports car? Indeed, a cursory glance at the particulars of Clooney's new vehicle, the Tango, suggests that it wouldn't be out of place alongside the Porsches and Ferraris in any A-list celebrity's garage.

But surprisingly for such a high-performance car, the Tango is an electric vehicle. And more surprisingly still, it is just 2.6m long and 1m wide, narrow enough to take up half the width of a normal driving lane. A Smart car is 1.5m wide.

To prevent its lack of width making it tip over when cornering, Tango's creators have kept its centre of gravity low by placing the 500kg battery pack within its floor. The vehicle can weave in and out of slow-moving traffic like a motorcycle, while its driver and passenger are completely enclosed within the roll-cage and carbon-fibre body of a sports car.

Halving the width of cars to potentially double the number of vehicles on existing roads is one interesting option being considered for tackling the growing congestion problems in towns and cities throughout the world, particularly as most trips to and from work are made by a driver with no passengers.

Commuter Cars hopes the Tango will help tackle the crippling traffic jams and increasingly strict emissions regulations in California — where there are also plenty of residents with the disposable income to afford its price tag.

The high cost of the vehicle, and the fact that its heavy lead acid battery pack needs recharging every 100 miles, mean it is unlikely to have a huge impact on the UK market. But Geoff Bye, project manager for the Tango programme at Prodrive, said the company hopes it will spark interest in the concept of narrow vehicles among consumers and car makers.

'This vehicle is too expensive, so the price has got to come down,' he said. 'But this is the early DVD or CD player — the first one to market is going to be very expensive and not really attainable by everybody. But it starts the ball rolling, and other manufacturers begin to come in and introduce a product that is better value for money and has better performance, and that is when the market will really take off.'

Prodrive has a particular interest in raising demand for narrow cars, as the company is developing its own concept, Naro, in conjunction with its ex-engineering director Hugh Kemp, who has now established the Narrow Car Company.

Naro is a fully enclosed, two-seat four-wheel vehicle with the banking action of a motorbike to prevent it tipping over when cornering. The vehicle is 1m wide, 2.5m long and 1.7m high — taller than a Ford Galaxy or Renault Espace — offering good visibility to allow the driver to see and plan ahead when moving through traffic.

'By having four wheels on the vehicle, and a steering system that would make it steer exactly like a car, we believe it will be more of a car driver's motorcycle than a motorcyclist's. We're aiming to capture the car drivers who want a bit of fun and the ability to drive more quickly through cities and park more easily,' said Kemp.

Having spun the project out of Prodrive early in 2004, Kemp has spent the past year refining the vehicle's designs and securing funding to allow him to carry out his three-year programme to prepare the concept for commercialisation. This work has recently included further research with Prodrive, the project's engineering partner, into the vehicle's roll and steer system, funded by the Welsh Development Agency.

A key factor in the design will be convincing people that Naro is as safe to drive as a conventional car. Kemp insists the vehicle's height will mean it will score highly on active safety, as drivers will be able to spot potential hazards further ahead and steer themselves out of danger.

In a side impact the safety levels will be identical to a conventional car, as the distance from the driver's centre line to the outside of the vehicle will be exactly the same, but just on both sides, he said. The car's low inertia when compared to larger vehicles will also mean it is likely to be shunted forwards or sideways in a collision rather than crushed, as it will not be held back by its own weight.

But these are not easy messages to get across, and many people are likely to make a snap decision on how safe the vehicle is, based purely on its size. So convincing the public they will be safe driving around in a narrow car is also about styling, he said.

'We had to demonstrate very strongly in the vehicle's styling that we've built a cage around you,' said Kemp.

'The latest schemes of the design are showing more of a skeleton, an aluminium-extruded spider structure that comes across the top of you, which gives you the feeling that you are contained in a kind of crash helmet.'

The company now plans to build the vehicle's understructure from carbon fibre, including exposed carbon fibre in the seating platform, to emphasise to drivers the fact that they are benefiting from Formula One-style safety.

Kemp has also been looking into engine options for Naro, and is investigating the use of Rotax or Yamaha quad bike engines. These are small enough to be neatly packaged within the vehicle without taking up too much space inside, but unlike motorbike engines they have automatic transmissions and a reverse gear. The vehicle will be capable of up to 85mph, allowing it to hold its own on dual carriageways and motorways.

The team has chosen to stick with existing engine technology rather than opting for an emerging, more environmentally friendly option such as the fuel cell, as the vehicle is already 'strange' enough without further complicating matters by working with technology that is not yet sufficiently mature.

But because the vehicle is so light, its carbon footprint will nonetheless be significantly reduced, said Damian Harty, Prodrive's chief dynamics engineer. It takes as much energy to make a car as it does to drive it for 100,000 miles, he said. So simply making a vehicle 300kg rather than 1,200kg eliminates three-quarters of the manufacturing footprint, and takes almost 40 per cent off its overall carbon footprint.

Added to this is the improved fuel efficiency of a very light and aerodynamic vehicle.

'A motorbike that has the same fuel economy as a Ford Focus is good for well over 180mph, and does 0-60 in three seconds, so in terms of its performance it compares much more with a Lamborghini. So if you go to a motorbike that performs more like a Ford Focus, then you get 80/90/100mpg. On top of that, Naro has got aerodynamic improvements that are massive compared to a motorbike, because bikes are obviously a very irregular form so they're very bad aerodynamically.'

The car's low weight may also one day, Harty said, enable it to make far more efficient use of fuel cells than heavier, more power-hungry vehicles. 'The important thing is that Naro is not predicated on a particular power source technology. It is easier to halve the weight of the car by making half a car than it is to double the efficiency of something that's been optimised for the past 100 years.'

The Narrow Car Company is planning to launch the vehicle as an executive commuter car in 2008, and Kemp believes he can make a viable business case for producing around 1,500 cars a year, at a cost of around £6,400 each. He also hopes to license designs for a taxi and city delivery vehicle based on the concept to other companies, and has had interest from London Taxis International (LDI) and LDV.

The cost of the commuter vehicle, which is lower than the Smart car (£6,800-7,800), will put it into close competition with another concept under development, the Compact Low Emission Vehicle for Urban Transport, or Clever.

Clever, being developed in an EU-funded collaboration including BMW and Bath University, is a three-wheel, two-seater with a tilting chassis, powered by compressed natural gas. Ben Drew, a Bath researcher working on the project, said a basic prototype of the vehicle should be built by May, when the team will begin modifying it, before a fully working prototype is unveiled in December. At present Clever, which has a top speed of 50mph, is being developed as a proof-of-concept project, but if the design is taken up by any manufacturer it is expected to cost around £6,500.

Prof Garel Rhys, director of the Centre for Automotive Industry Research at Cardiff Business School, said setting the right price will be key to ensuring narrow vehicles have a future. Rhys carried out a study on the potential market for the vehicles on behalf of the Welsh Development Agency, to help it decide whether to invest in the Naro project.

'There have been too many schemes where the product has looked right in a technical way, but when you see the price that people are looking for, they really are hoping that people put a great deal of value on doing the right thing for congestion and the environment. Frankly, very few people can afford to do that, so a greatproject flounders and disappears,' he said.

The partners behind both the Naro and Clever projects appear to have a more realistic view of what consumers will be prepared to pay for such a vehicle, although even with the right price the cars are only likely to be attractive to people who spend a vast amount of their time driving in urban areas, he said.

The study predicts that by 2015 there will be a potential market in the UK of 20,000 'sub-cars', a group including Smart, Naro, Clever and Dutch firm Vandenbrink's sporty three-wheeler, the £20,000 Carver. This is forecast to increase to 30,000 by 2025.

This market, the report claims, could emerge in part from around five per cent of motorbike buyers — 6,000 people a year — switching to narrow vehicles, and the cars themselves gaining a 'cool' and fun image, similar to the Smart. Incentives, such as exemption from congestion charges, bridge tolls and very low or complete exemption from road tax, could offer people more rational reasons to buy the vehicles.

Finally, any increase in fuel prices in the future will encourage people to consider more efficient vehicles, while CO2 agreements between the EC and the European Car Makers' Association (ACEA) could see firms using such ultra-light vehicles to offset the impact of their heavier, higher CO2-emitting 4x4s and MPVs. If the big car makers do become involved, this could help to increase demand further by bringing in customers loyal to certain marques, said Rhys.

'Even if you only manage to get one per cent [of the market], that is still very significant in terms of what these products have got in the past, and many of them are designed for quite modest production runs,' he said.

However, not everyone is convinced that narrow cars will take off, thanks in part to the failures of the Sinclair C5 and BMW's too expensive scooter-with-a-roof, the C1. Volvo's Monitoring and Concept Centre (VMCC) in California recently developed a two-occupant, capsule-shaped concept, called the Tandem, in which the passenger sits behind the driver.

But despite the advantages of potentially doubling the number of cars to each traffic lane and improving fuel efficiency, Volvo came to the conclusion that people are not ready for tandem-seater vehicles, according to Lars Erik Lundin, general manager of the VMCC. 'There is a social aspect to it — when you travel together you like to have eye contact,' he said.

As a result, the team moved on to developing the 3CC, an all-electric three-seater concept car with two seats in the front and one in the back. This is less than ideal in terms of reducing congestion, but still offers fuel-efficiency savings through the aerodynamic benefits of tapering the car towards the rear, he said. 'Our conclusion is that to make an impact on the environment we have to have quite a few people buying these cars, and we think a three-seater would be much more attractive than a tandem.'

But those working on narrow cars believe the growing number of two-seater projects in the pipeline is helping to build public awareness, and an expectation that such vehicles will soon be spotted driving around on our city streets.

This may be enough to overcome some of the prejudices surrounding the strangeness of narrow cars, said Prodrive's Harty.

'Providing Naro isn't in some way apologetic as a vehicle, can hold its head up high and look quite funky and not make people feel embarrassed, and works effectively, I hope with the right marketing we can overcome these issues.'

Prodrive
BMW
Bath University
Commuter Cars