Colourful concept cars often come with a hint of 'green'

Paul Boughton
Recent history in the automotive industry has seen manufacturers creating the usual mix of concept cars, some of which are precursors of future models, while others are simply outrageous. There have also been various ‘crossover’ concepts that attempt to answer two needs, such as vehicles that purport to offer a combination of sportiness and off-road ability.

In the past few years, however, manufacturers have increasingly opted to unveil concept cars that have a ‘green’ theme. The various cars’ environmental credentials relate to materials of construction, fuels, power trains, production methods and aerodynamics. At the British International Motor Show in the summer of 2008, many of the concepts exhibited had a ‘green’ aspect. Furthermore, the event itself featured a Greener Driving Pavilion.

Even Land Rover, which has traditionally manufactured vehicles in which off-road performance is given a higher priority than environmental performance, has taken a long, hard look at the environment in creating its LRX concept. Using lightweight materials, Land Rover says it has developed features that add to the vehicle's individuality and flexibility.

The three-door LRX cross-coupé, with its more compact size, lighter weight and sustainability-focused technologies, is said to offer the potential of 120 g/km CO2 emissions and fuel economy of 4.7 litres per 100 km (60 mpg) on the European combined cycle. Phil Popham, Land Rover's managing director, stated: “The LRX concept delivers the powerful message that we are as serious about sustainability as we are confident about the continuing relevance and desirability of our vehicles. LRX has unmistakable Land Rover design and the breadth of capability that you would expect from our vehicles. But it carries those essentials into a segment where the brand has never been before, and with a proposed level of efficiency that would make it one of the cleanest vehicles in its class.”

Land Rover’s LRX is designed as a highly fuel-efficient 2.0-litre, turbodiesel hybrid, capable of running on bio-diesel. In combination with other Land Rover technologies, this power train could reduce fuel consumption by as much as 30 per cent compared with other 4x4 cars of similar size. The concept's integrated Electric Rear Axle Drive (ERAD) is particularly significant in Land Rover terms, as it would enable the LRX to use electric drive alone at lower speeds while retaining full (or improved) off-road ability. Unlike the hybrid technology used by some other 4x4 cars, Land Rover's concept retains mechanical drive to all four wheels. Off-road, the ERAD would provide additional torque only when it is needed and, with maximum electrical torque available from standstill, this system offers even better low-speed control and enhanced pull-away on difficult surfaces. On the road, the ERAD would allow low-speed traffic creep at speeds of up to 32 km/h (20 mph) on electric power alone, with the integrated starter-generator (ISG) restarting the engine automatically when needed. The electric drive would then continue to assist the mechanical drive until the engine is running in its most efficient range, thereby benefiting both fuel consumption and CO2 emissions. The ISG control system would also stop the engine automatically when the vehicle halts in traffic, and restart it quickly and smoothly as required.

Of course, the LRX is not solely an exercise in environmentally-aware off-road driving. For example, on either side of the horizontally-split, power-operated tailgate, there are removable speakers with an iPod docking station. The tailgate has two padded seating areas, between which are integral aluminium cup holders, and there is also a coolbox and a bottle chiller.

Sports cars

Some people might find it surprising that a company such as Land Rover is focusing on the environment with a class of vehicle that is not generally thought of as being 'green', but the same could also be said of sports car manufacturers. Nevertheless, companies such as Morgan and Lotus are also working on ‘green’ projects. The Morgan LIFECar, for example, was unveiled at the Geneva Motor Show in March 2008. RiverSimple, which led the project, says the LIFECar (lightweight integrated fuel-efficient car) summarises the company’s three key design principles: whole-system design, energy efficiency and resource minimisation. Hugo Spowers, the founder of OSCar Automotive and managing partner at RiverSimple, sought to demonstrate with the LIFECar project that significant gains in fuel efficiency could be achieved with readily available technology – though little information has so far been released about the supercapacitors in which the LIFECar would store energy. In order for this project to take place, and with the support of the Morgan Motor Company, Spowers formed the LIFECar consortium with Cranfield University, Linde, Oxford University and QinetiQ.

The LIFECar combines a hydrogen fuel cell with a bank of ultracapacitors such that cruise and acceleration requirements are decoupled and resolved in a highly optimised fashion. By combining these technologies with a lightweight structure, the LIFECar is intended to achieve a combination of performance, cost-effectiveness and fuel efficiency. To keep the weight down to the target of 650 kg, the LIFECar uses technologies that Morgan currently employs in its Aero 8, including bonded aluminium and laminated wood. For the hydrogen fuel tank, carbon fibre is wound around a drum.

Oxford University undertook the design of the electric motors, which are reported to be 92-94 per cent efficient across their operating range. Four motors are used, all mounted inboard to minimise the unsprung weight and help to improve the car's ride and handling. Drive to each wheel is via a small gearbox.

Crucial to the success of the vehicle will be the PEM (polymer electrolyte membrane) fuel cell stack, and this has been provided by QinetiQ to meet the specific needs of the LIFECar. Consisting of four 6 kW sub-stacks, the complete fuel cell achieves a quoted efficiency of 45 per cent. Furthermore, the regenerative brakes are said to enable up to 50 per cent of the kinetic energy to be converted to electricity, whereas the norm for regenerative braking is typically around 10 per cent. Cranfield University developed the management systems for the vehicle, fuel cell, ultracapacitors, motor/generators and hydraulic brakes – which are employed at low speeds.
Linde provided the hydrogen refuelling expertise.

Lotus, which has always had a philosophy of ‘performance through light weight’, could be said to have a head start in the race to produce an environmentally-friendly sports car. The Lotus Eco Elise technology demonstrator, which was shown for the first time at the British International Motor Show, is said to promote a different perspective on ‘green’ – one that does not revolve solely around CO2 emissions – and is in keeping with the company's stated desire to become the world’s ‘green’ automotive consultancy.

Sustainable materials including locally farmed hemp, eco wool and sisal have been developed for body panels and trim and, combined with new water-based paints developed with Du Pont, showcase new technologies that are both environmentally friendly and affordable. In addition, solar panels have been set into the double-curvature hemp roof panel to help power the electrical systems and provide a means of renewable energy generation. There is also an 'economy' gear change display to improve fuel efficiency and promote greener driving. The 'green' credentials of the technologies demonstrated in the Eco Elise have been analysed throughout the lifecycle of the car.

The Eco Elise weighs 32 kg less than the standard Elise S, which means that the efficient Elise S engine in the Eco Elise will give higher fuel economy figures – and even better performance.

Natural materials

New materials for the Eco Elise have been carefully studied to ensure that each technology reduces the overall environmental impact of the vehicle. The life of the components has been analysed during the production stage, use, and at the end of the vehicle's life. The technologies aim to offer lower emissions of solvents and CO2 in the lifecycle of the vehicle, with reductions in energy consumption during manufacture.

Hemp has exceptional material properties that make for a very strong fibre. Sustainable hemp technical fabrics have therefore been used as the primary constituent in the high-quality A class composite body panels and spoiler. Hemp has also been used in the lightweight seats. An additional benefit of hemp is that it is a natural resource that requires relatively low energy to manufacture and absorbs CO2 while growing. This hemp is used with a polyester resin to form a composite, and it is hoped that a fully recyclable resin will be viable in the near future.

The Eco Elise seats are upholstered in a durable yet biodegradable woollen fabric that has been given the EU Flower certificate to exemplify its environmental credentials. This new material is ethically produced and does not use any dyes or harmful processing. In fact the colour is created from the selection of sheep breeds used to produce the wool for the yarn, which increases the natural feel of the wool and reduces the processing of the cloth.

Sisal is a renewable crop that, like hemp, is used for its strong material properties. Sisal has been used for the carpets in the Eco Elise, as it is tough and abrasion-resistant.

Another ‘green’ two-seater unveiled at the British International Motor Show was Honda's Open Study Model, which was shown alongside the FCX Clarity, Honda's zero-emission fuel cell vehicle that has just entered small-scale production. The lightweight OSM roadster design study is said to display one of Honda’s core engineering principles – to design stylish and exciting cars that are also environmentally responsible. Andreas Sittel, project leader for the OSM, commented: “We are trying to show that low-emission cars can be attractive. There is no reason why a car that is more environmentally friendly cannot look great too – and be sporty and fun to drive.”

The concept for the project was ‘Clean and Dynamic’. Honda describes the exterior design as a balance of smooth, rounded curves and sharp lines to provide definition in key areas. Inside, the uninterrupted, fluid approach is continued, with long sweeping curves extending from both door panels to form a frame for the instrument display. The concept for the dashboard was to avoid creating the traditional block of 'heavy' colour and material in front of the driver. For that reason, the dash is broken into sections, with the most important instruments being directly in the driver's line-of-sight.

Honda’s OSM was designed at the company’s research and development facility in Offenbach, Germany, following the Honda Small Hybrid Sports Concept (Geneva 2007) and the Accord Tourer Concept (Frankfurt 2007). At present the Honda OSM is a design study model, with no plans for it to enter production.

From concept to production

Some concepts, however, do enter production. For instance, the new Renault Laguna Coupé bears a close resemblance to the concept car revealed at the Frankfurt Motor Show in September 2007. The production model even features the concept's Active Drive chassis with four-wheel steering. Developed jointly by Renault engineers and specialists from Renault Sport Technologies, the Laguna Coupé’s Active Drive chassis is said to achieve outstanding agility and stability for safety and surefooted handling, as well as enabling the car to corner with excellent precision.

At low speeds the Active Drive chassis and four-wheel steering enhance manoeuvrability. In urban driving, as well as on twisty roads, the car is said to be easy to drive yet offers outstanding handling precision. Furthermore, the Active Drive chassis with four-wheel steering excels not only under braking in difficult conditions, but also when taking avoidance action (often known as the ‘elk test’).

A more striking vehicle from Renault is the Mégane Coupé Concept, which is claimed to preview a compact coupé that will be released at a later date. Like its larger sister, the Laguna Coupé Concept, it points the way to a more fluid, sportier styling from Renault. According to Renault, The Mégane Coupé Concept is targeted at drivers who are “not only drawn by the notion of driving pleasure but who also seek to express their personality through their car.” Renault's vision of what a genuine compact sports coupé should deliver, namely character and dynamism, are said to be epitomised by the opening and closing movement of the Mégane Coupé Concept's spectacular ‘dragonfly’ doors.

Another French concept car, but one with more emphasis on ‘green’ credentials, is the Citroën C-Cactus that was first shown in Frankfurt in 2007. One of the aims of the C-Cactus design is to reduce the number of components. And a benefit of this approach is that the vehicle weighs just 1180kg and can therefore achieve a fuel consumption of just 2.9 litres per 100 km (97.4 mpg) on the combined fuel consumption cycle. Using a hybrid HDi drive train, a production version could, if it ever came to market, achieve CO2 emissions of 78 g/km. It should also be reasonably priced, costing about the same as an entry-level Citroen C4.

To minimise the environmental impact of the C-Cactus, there is considerable duplication of parts to reduce production costs and waste; for example, the front and rear bumpers are the same component. Another innovative feature is that the windows do not open, as air conditioning makes this unnecessary. Consequently the design saves further weight and cost by incorporating simpler, lighter windows.

Materials of construction are also sustainably sourced: the protective floor mats are made of leather off-cuts that would otherwise be discarded; some internal parts are made of natural cork; and some of the cloth is felt made from wool.

Small and clean

At the 2008 Auto Expo 2008 in New Delhi, India, Suzuki Motor Corporation introduced its Concept A-Star. Designed to compete with A-segment cars such as the Fiat 500, Renault Twingo and VW Fox, the five-door hatchback is said to reflect a focus on world-class environmental compatibility and comfort. It will have a newly developed Euro 5-compliant 1.0-litre aluminium petrol engine with CO2 emissions that are claimed to be lower than those of European competitors. The engine will be produced by Maruti Suzuki India, and a manual transmission for it will be manufactured by Suzuki Powertrain India.

The Concept A-Star is the first concept car with which designers from Maruti Suzuki India’s research and development division have been involved from the beginning of styling development. A production model will inherit some of the design themes from the Concept A-Star and be built at Maruti Suzuki India's Manesar plant for sale mainly in Europe but also in India and other countries. Production is due to start in October 2008. Meanwhile, the concept car’s styling includes pink accents that allude to the production model's main target customers.

While the Concept A-Star has much in common with a production vehicle that will be available to purchase within a matter of months, the same cannot be said for the BMW Gina (Geometry and functions In ‘N’ Adaptions) Light Visionary Model concept, with its highly unusual body covering. Unlike most concept cars, however, the Gina is intended to be used as a research platform. The Gina Light Visionary Model dispenses with the usual body elements found on production vehicles; instead, a new structure with a minimum number of components has taken their place. A special, highly durable and extremely expansion-resistant fabric material stretches across a metal structure. The body exterior consists of only four elements: the largest component extends from the front of the vehicle to the edge of the windscreen and down the sides to the rear edge of the doors; large side panels start at the front where the rocker panels emerge and run across the rear wheel arches into the rear; and a fourth component is the central rear deck element.

Beneath the surface

Importantly, the driver can move some elements of the substructure by means of electric and electro-hydraulic controls. Moving these substructure elements also changes the shape of the outer skin, thereby adapting it to suit the current situation, the driver’s requirements and to enhance the car's functional range. One example of this is the headlight design. When the headlights are switched off they are hidden under the fabric cover. But as soon as the driver turns on the lights, a metal structure beneath the skin moves, opening the previously closed fabric cover to reveal the headlights. A similar technique is used for the rear spoiler – which is only activated at speed – and to enable the ‘doors’ to swing outwards and upwards for driver and passenger access and egress. Other panel adjustments can be made to improve airflow over the body, and a slit can be opened along the centreline of the 'bonnet' to provide access to engine service points.

While the BMW Gina Light Visionary Model might seem extreme in its approach to vehicle bodywork, the Mazda Furai concept car is extreme in other respects. Launched at the Detroit motor show in January 2008, and later demonstrated at the Goodwood Festival of Speed, the two-seater, mid-engined, rear-wheel drive 290 km/h (180 mph) Furai is the raciest interpretation of Mazda's Nagare design language (the ‘embodiment of motion’).

The Furai was created at Mazda North American Operations’ (MNAO) studio in Irvine, California, with the aim of developing a car that blurred the boundaries between road-car and racecar. The team started with a Courage C65 carbon-composite racecar chassis (successfully campaigned in the LMP-2 class of the American Le Mans Series), complete with its 1962 cc, 450 PS Mazda triple-rotor rotary-engined, then added a closed cockpit and Nagare design elements. But while the four previous concept cars explored Nagare's emerging design aesthetic, every element of the Furai’s textures and details is claimed to serve a functional purpose.

Channelling, the flow of air rather than just visually interpreting it, Furai's Nagare ‘flow lines’ are claimed to enhance the vehicle’s aerodynamic performance by directing air under, over and around the body.

Although it could be argued that the Furai’s improved aerodynamics help to improve fuel economy, it has to be accepted that not all of the current crop of concept cars are being used to demonstrate the manufacturers' environmental ambitions ­­– which is good news for those who view cars as more than just a means of getting from A to B.

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