Renault Unveils EOLAB Plug-In Hybrid (w/videos)

3 years ago by Mark Kane 28

Renault EOLAB

Renault EOLAB

Renault EOLAB

Renault EOLAB

Renault, the only car manufacturer that had four all-electric models on the market (Fluence Z.E., Kangoo Z.E., ZOE and Twizy) announced that its EOLAB plug-in hybrid will make its world premiere at the 2014 Paris Motor Show.

The name comes from combining the name of “Aeolous” God and Ruler of the Winds in Greek mythology, and “Laboratory”.

According to the French company, this concept car will consume just 1 liter of gasoline per 100 km (62 miles) on NEDC cycle (282 mpg).  However, it is a highly optimistic cycle and this figure is achievable only when the first 66 km are driven in all-electric mode.

The Renault EOLAB includes roughly 100 production-destined technological innovations, which will appear gradually on production Renaults before 2020.

The main improvements are 400 kg (881 lbs) weight reduction (whole car weight just 955 kg / 2,105 lbs), aerodynamic coefficient of just 0.235 Cd and Z.E. Hybrid Powertrain.

Z.E. Hybrid Powertrain consists of a 1.0-litre 3-cylinder 57kW (75hp) and peak torque of 95Nm SCe petrol engine and “a permanent magnet electric motor (axial flux discoid motor in the case of the prototype)” with 50 kW and 200 Nm of torque, powered by a 6.7 kWh battery.  There is also an “Innovative patented clutchless 3-gear transmission“.

Renault believes that it will be able to introduce on the market an affordable B-segment car based on EOLAB within 10 years.

Renault EOLAB

Renault EOLAB

Renault flooded us with a press release “book” and hundred of photos on this vehicle:

Renault EOLAB

Renault EOLAB

Technologies geared to achieving ultra-low fuel consumption for all

For Renault, the purpose of EOLAB is to remain true to the company’s DNA by ensuring that ultra-low fuel consumption becomes a reality for as many people as possible. This in turn means making its technologies available at a price that people can afford. EOLAB features materials such as magnesium and aluminium, which are extremely light and also much cheaper than titanium. Meanwhile, the notion of such a car being produced in large numbers within the next 10 years was dialled into the plan from the very start.

100 technological advances for future Renaults

EOLAB is much more than just a styling exercise or a mere shop window. Conceived around a B-segment platform, the prototype incorporates around 100 new, realistic technological developments that are designed to be introduced gradually on upcoming Renault vehicles.

EOLAB’s recipe

The EOLAB prototype’s exceptional fuel economy – namely 1 litre/100km – is the fruit of work on three main fronts: refined aerodynamics, weight saving and Z.E. Hybrid technology (petrol/electricity):

  • The car’s shape was designed to slice through air efficiently, while movable devices such as an active spoiler and lateral vanes perform the same way as ailerons.
  • A weight saving programme brought the car’s mass down 400kg, thanks in particular to a multi-material body shell combining steel, aluminium and composites, as well as a remarkable magnesium roof that tips the scales at barely 4kg. Saving weight was a virtuous circle since it enabled the size, and therefore the cost of the prototype’s chief assemblies (engine, battery, wheels, brakes, etc.) to be kept low, thereby financing the decision to employ certain more costly materials;
  • Z.E. Hybrid technology: this new, compact and affordable hybrid power unit combines ultra-low fuel consumption with zero-emission mobility* for journeys of less than 60km and at speeds of up to 120kph. In coming years, Z.E. Hybrid technology will become complementary to Renault’s zero-emission* electric vehicle range.
Renault EOLAB

Renault EOLAB

A contribution to the French government’s ‘New Industrial Plan’

EOLAB forms part of the ‘fuel consumption of 2 litres/100km for all’ plan introduced within the framework of France’s so-called New Industrial Plan. However, EOLAB goes further than the fuel consumption target set by the French government since it sets its sights on the much longer term. In the course of the prototype’s design, Renault developed the technologies necessary for the introduction of a car with fuel consumption of just 2 litres/100km by 2020. To achieve this, Renault worked in a spirit of collaborative innovation with French automotive industry partners like car glass manufacturer Saint-Gobain, seat supplier Faurecia, tyre company Michelin and Continental (brake system). Renault also worked closely with major partners like the Korean company Posco (magnesium components). The specific know-how of all these partners made a valuable contribution to the success of the EOLAB prototype.

EOLAB Concept: a concept car to capture the imagination

Renault’s designers were closely involved with the EOLAB project from its very early days. In the case of EOLAB Concept, they pushed the design parameters to perfect the car’s styling and paid significant attention to detail in order to optimise aerodynamics and weight. With its sloping roof and breathtakingly slender rear end, the concept car’s true purpose is well masked: beneath its seductively designed shell, everything is geared towards frugality. It demonstrates that Renault is able to add a touch of dream-like magic to a prototype whose fundamental mission is to achieve ultra-low fuel consumption.

Renault EOLAB

Renault EOLAB

EOLAB: Overview

  • Around 100 new, realistic technological developments designed to be introduced gradually on new production Renaults from now until 2020
  • Aerodynamics of 0.235 Cd (30 per cent less than equivalent Clio)
    • Active ride height: Access mode, Urban mode and Extra-Urban mode
    • Active wheels – react to brake temperature to maximise Cd
    • Active front spoiler
    • Active rear flaps
  • Weight savings across the entire vehicle (400kg over equivalent Clio)
    • Asymmetric 3-door layout
    • Compact revised brakes – no master cylinder & all systems integrated into one small lightweight unit
    • Narrow 145/45R17 Michelin ultra-low consumption tyres
    • Ultra-thin windscreen glass (3mm) – saves 2.6kg
    • Thinner interior trim & lighter plastics containing air bubbles
    • Optimised seat structures – save 12kg and 30mm in car length
    • Lightweight dashboard cross member
    • Lighter running gear – steel to aluminium
    • Magnesium roof weighs just 4.5kg
    • Brakes are 14.5kg lighter but retain the same braking efficiency
    • Fixed bonnet gains 2.5kg
    • LED front lights
    • Lithium –ion battery
    • Compact centre-exit exhaust system to save weight
  • 100% Renault Z.E. Hybrid powertrainHuman Machine Interface – connectivity and real-time eco-driving information
    • 1.0-litre 3-cylinder 75hp SCe petrol engine
    • 400V, 6.7 kWh battery with 66km range
    • Innovative patented clutchless 3-gear transmission
Renault EOLAB

Renault EOLAB

Renault EOLAB

Renault EOLAB


EOLAB is an eloquent demonstration of Renault’s determination to take ever greater steps to reduce the carbon footprint of its vehicles. The goal is to make ultra-low fuel consumption an affordable reality to as many motorists as possible.

As a pioneer in the field of zero-emissions mobility thanks to its range of electric vehicles, and also as the 2013 market leader in terms of fuel consumption and average CO2 emissions, Renault is the only manufacturer to have set a target of reducing its carbon footprint by 10 per cent over three years (2010-2013). That goal was achieved in 2013 and the brand continues to be committed to reducing the CO2 emissions of its vehicles during road use, which accounts for about 85 percent of the company’s total carbon footprint. Thanks to its range of all-electric vehicles and increasingly efficient internal combustion engines, the Renault Group recorded the lowest CO2 emissions figures of all European manufacturers in 2013 (less than 115g/km)*.

* Average CO2 emissions over an NEDC-homologated combined cycle of Renault group passenger vehicles registered in 2013, taken across 23 countries (all of the EU except Cyprus, Malta, Romania and Bulgaria). Source data from AAA-DATA (Association Auxiliaire de l’Automobile), a CCFA subsidiary. AAA-DATA is an association that manages automotive industry data for public authorities.

* No CO2 or other regulated polluting emissions during road use.

Renault EOLAB

Renault EOLAB

The introduction of EOLAB takes Renault’s environmental programme to an even higher level. The target? To make ultra-low fuel consumption as widely available as possible by creating a prototype which blends a raft of cutting-edge features that are realistic in both technical and financial terms.

EOLAB’s purpose is to highlight Renault’s savoir-faire in the fields of design and technology. It is a statement of the company’s environmental strategy which strives to reduce the carbon footprint of its vehicles across successive generations.

It packs about 100 technological features that will be introduced gradually to the model range over the next 10 to 15 years with a view to meeting the following targets:

  1. Meet various legislative requirements in different markets and also the Group’s commitment to reduce its global carbon footprint (Renault is aiming for a 10 percent fall between 2013 and 2016).
  2. Meet customers’ expectations by increasing energy economy and cutting running costs at a time of uncertainty about the availability and price of resources.
  3. Improve air quality in towns and cities, in line with the wishes of public authorities and motorists.

Renault’s internal combustion engines have become significantly more fuel efficient over the past decade or so.

Technological breakthroughs in terms of construction materials and vehicle design (for lightness, aerodynamic efficiency, etc.) will enable further savings to be made in the future.

The increasing electrification of powertrains is symbolic of both improving fuel economy and an opportunity to reduce vehicles’ CO2 emissions. It will also gradually increase the influence of renewable energies and improve overall energy efficiency from well to wheel.

EOLAB’s powertrain benefits from expertise acquired during the development of the Group’s electric vehicle range which remains unmatched even today. The technology it packs is innovative in the sense that it enables users to cover substantial distances in built-up areas without any exhaust emissions, then if necessary switch over to a conventional internal combustion engine to continue the journey. As with all Renault projects, the chief challenge was to develop a solution that is affordable to as many people as possible, and thus liable to sell in high numbers. That’s a vital consideration if we are to have a significant effect in terms of environmental benefits.

Different countries’ energy supplies and contrasting usage patterns are pushing manufacturers to expand their ranges and diversify according to local market conditions. As part of the Renault-Nissan Alliance, the Renault group intends to maintain its status as a worldwide market leader in the field of electric vehicles. PHEV (plug-in hybrid electric vehicle) solutions, such as that featured on EOLAB, complement this range and will be developed to suit widely differing driving patterns… but always with the goal of covering significant distances with “zero emissions”*.


Without a constant stream of technological breakthroughs, the car’s environmental impact would diminish only through models gradually being replaced by others with cleaner internal combustion engines. In that respect, the pace of change is often linked to legislative changes affecting emissions.

This is why Renault thinks outside the box, offering ground-breaking technological innovations that are accessible to all. Firstly it has its all-electric vehicles, which emit no CO2 or other compounds from their exhausts, don’t create any smells and operate silently. Renault is the only manufacturer to offer a comprehensive range of four electric vehicles. Now, through its EOLAB project, Renault is extending zero-emissions mobility thanks to the development of an innovative hybrid system – Z.E. Hybrid – which allows users to cover trips of up to 60km* at speeds of up to 120km/h with absolutely no tailpipe emissions.

Zero-emissions mobility: an effective way to tackle poor air quality

According to a scientific modelling study of the Earth’s atmosphere, conducted using data from the city of Rome, achieving a 20 percent rate of zero-emission vehicles in the central traffic area would greatly reduce the concentration of pollutants that might be dangerous to our health. In the most polluted streets, calculations revealed a reduction of up to 30 percent for particles that cause respiratory or cardiovascular problems, and up to 45 percent for CO2, a significant respiratory irritant.

Alongside Renault’s existing range of four electric vehicles, the Z.E. Hybrid proposal is an effective new measure against this threat to public health.

* No CO2 or other regulated polluting emissions during road use.

Renault EOLAB

Renault EOLAB


A weight saving of 400kg – Aerodynamic efficiency improved by 30% – Z.E. hybrid technology

The record fuel consumption achieved by the EOLAB prototype is the fruit of work in three fundamental areas:

  • Carefully-honed aerodynamics which achieved an improvement of 30%.
  • EOLAB’s weight is around 400kg lighter than that of a B-segment hatchback like the Clio IV.
  • In addition to benefiting from the above work, the Z.E. Hybrid powertrain is the sort of hybrid solution that will be seen on future Renault vehicles.

Key figures:

  • A weight saving of 10kg equates to a CO2 saving of 1g/km (NEDC cycle)
  • Aerodynamic efficiency: a reduction in drag (CdA) of 0.100m2 equates to a fuel consumption saving of 0.1 litres/100km (equivalent to 3.7g of CO2/km).

EOLAB = a reduction of 0.170m2, a saving of 1.2 litres/100km on motorways (40g of CO2/km).

Renault EOLAB

Renault EOLAB


Drag coefficient (CdA) reduced by 30 percent

EOLAB’s CdA is 0.470m2 (A = 2.00m2 / Cd = 0.235) which represents an overall reduction of 0.200m² (around 30 percent). This lower drag coefficient results in a significant fuel consumption reduction at higher speeds. At a stable speed of 130kph, for example, it accounts for a fuel consumption saving of 1.2 litres/100km in comparison with the benchmark vehicle.

This exceptional aerodynamic efficiency was achieved by combining several factors:

  • Ground-breaking vehicle architecture, an innovative approach which includes a narrower rear track and a lower roofline without detracting from cabin space.
  • Carefully designed rear body panels.
  • Incorporation of active systems for even greater aerodynamic efficiency.

NOTE: the measure of a vehicle’s overall aerodynamic efficiency is its CdA, i.e. the vehicle’s frontal section (A) expressed in square metres multiplied by its drag coefficient (Cd). The CdA of the Clio IV, for example, is 0.670m², which is a good average for its segment. However, CdA gains should not be achieved to the detriment of design considerations or other characteristics, such as cabin space.

Variable ride height

EOLAB’s ride height is variable thanks to the use of active air suspension. The four dampers can be raised or lowered by 25mm in relation to the default setting. When the car is parked, the suspension switches to its highest position in order to facilitate entry. As the vehicle begins to move, the suspension resumes its default setting (i.e. it lowers by 25mm) at speeds of between 5 and 70kph in order to limit the amount of air that passes underneath it. For the same reason, the ride height is lowered by a further 25mm at speeds in excess of 70kph.

Renault EOLAB

Renault EOLAB

Active spoiler

At the same time, the aerodynamicists focused on a variety of technological solutions and innovations. EOLAB’s front bumper, for example, is equipped with an active spoiler that lowers by 10cm at speeds in excess of 70kph in order to restrict airflow beneath the car. Even when a vehicle is designed with a flat underbody, there are still a number of asperities that can detract from aerodynamic efficiency.

Aerodynamic flaps

Another mobile feature of EOLAB’s aerodynamic package is the 40cm x 10cm vertically-positioned flaps that are visible on the rear bumper, rearward of the rear wheels. At speeds in excess of 70kph, these flaps open by 6cm in order to ensure that as much of the airflow as possible stays attached to the vehicle as it moves forward. Without this solution, passing air has a tendency to become detached from the vehicle’s sides too early after passing the rear wheels and this has a negative effect on drag. In the open position, airflow remains attached to the car as far rearward as possible, right to the trailing edge of the bumper. “These flaps tauten the airflow and prevent turbulence which otherwise acts as a sort of aerodynamic brake,” explains William Becamel, the aerodynamics expert who worked on the project.

Renault EOLAB

Renault EOLAB

Active wheels

The teams that worked on EOLAB took a close look at its wheels, too. In a perfect aerodynamic world, the rims would be covered and smooth. This is rarely the case, however, essentially for design- and brake cooling-related reasons. An ingenious system was consequently designed whereby the rims are covered whenever the brakes do not need to be cooled, thereby reconciling design and aerodynamic efficiency considerations. The system is controlled by a temperature sensor built into the rims.

Tyres that slice through air

To further perfect EOLAB’s aerodynamic performance, it is fitted with particularly narrow, 145mm-wide tyres. That’s 40mm narrower than the smallest tyres available for the Clio IV. Michelin and Renault’s designers worked on the tread pattern to give a visual impression of width, while the sidewalls were designed to exude an impression of light weight. At the same time, tyre supplier Michelin optimised the casing and tread to minimise rolling resistance while maintaining excellent levels of safety and performance. The tyres’ rolling resistance is 15 percent lower than those of the Clio IV which itself is quite strong in this area. These tyres are also lighter, and their profile has been honed to minimise drag. Meanwhile, Renault has changed the technology used for the wheel bearings in favour of a more efficient solution that has achieved a CO2 emissions saving of 1g/km.

(For further information, see appendix at the end of this document)

Renault EOLAB

Renault EOLAB


EOLAB tips the scales at 955kg. That’s more than 20 percent lighter than the benchmark vehicle. Total weight savings amounted to no less than 400kg thanks to the teams’ holistic approach. This ambitious programme called for extensive work and outside-of-the-box thinking from the different specialists involved.

  • Body: 130kg saved,
  • Trim and equipment: 90kg saved,
  • Suspension: 70kg saved,
  • Engine peripherals: 30kg saved,
  • Powertrain: 60kg saved,
  • Electrical equipment: 20kg saved,
  • Z.E. Hybrid powertrain (including battery): 145kg added

Total weight = 955kg

The virtuous circle of shedding weight

While delivering the same level of performance, lighter vehicles require less energy to move forward. One of the chief focuses in the case of the EOLAB project consequently consisted in reducing the vehicle’s overall weight. This in turn meant that the vehicle’s principle assemblies (powertrain, brakes, running gear, cooling system, fuel tank, etc.) could also be lighter, and these additional savings compounded the initial groundwork.

“The savings achieved by taking a fresh look at the size of the different mechanical assemblies enabled us to cover the cost of using more expensive materials and technologies elsewhere without losing sight of the aim not to add to the overall cost.” Laurent Taupin (EOLAB Project Leader).

Because it is lighter and more streamlined, EOLAB needs less energy to be moved forward. It was therefore possible to revise the amount of power necessary to drive it in order to arrive at a result that ensures running costs comparable with those of a current vehicle, without scrimping on acceleration performance. Equipped with a battery of just 6.7kWh (total energy), EOLAB permits zero emissions motoring* for a distance of 60km** at speeds of up to 120kph, a scenario which covers the majority of everyday needs.

* No CO2 or other regulated polluting emissions during road use.

** Consumption, emissions and range data homologated in accordance with appropriate legislation.

The right material for a given job

To reduce a car’s weight, a well-trod path is to replace steel with lighter materials. All-aluminium and aluminium/carbon solutions already exist but, in addition to the high cost associated with such materials, they often necessitate an in-depth review of assembly and production processes, and there is a price to pay for that.

True to its philosophy, Renault chose to steer clear of radical solutions. “You can always save weight if you’re prepared to pay the price, but that would be contrary to Renault’s philosophy. Our strategy is to reduce weight in a way that benefits everybody. That means finding economically viable solutions that our customers can afford. Our approach can be summed up by the phrase: ‘the right material for a given job’,” underlines the EOLAB Project Leader Laurent Taupin.

This undertaking to contain costs went hand-in-hand with a significant constraint, however, and that was to identify weight-saving solutions that are compatible with today’s production processes.

A lightweight multi-material body shell

Employing the right material for a given job involved conceiving an innovative body shell that combined different materials selected as a function of their weight, cost and necessary production processes. EOLAB’s body shell consequently combines steel, aluminium, magnesium and plastic composites, whereas the majority of today’s cars are made of a single type of material.

1. Steel: extensive use of Very Very High Elastic Limit steels (VVHEL)

Over and above changes to a car’s basic architecture, the only way to lighten steel components is to use thinner metal. However, since detracting from a given part’s functional properties was out of the question, it was necessary to upgrade the mechanical properties of the steels employed at the same time. Renault consequently turned to Very Very High Elastic Limit steels which have a yield strength of between 1,200 MPa and 1,500 MPa, an improvement of between 200 MPa and 500 MPa over the VHEL steels used for current Renault models. With a tensile strength of up to 150kg/mm2, these grades were employed wherever their use served a real purpose, notably for the front part of the cabin. Their use requires a process known as hot stamping which Renault already uses for its production cars.

Renault EOLAB

Renault EOLAB

2. Aluminium

EOLAB’s highly innovative shell features a significant proportion of aluminium in different, readily available forms such as sheeting, castings and profiles.

Like steel, upgrading the mechanical properties enables thinner grades to be used with no detriment to a part’s function but with an additional weight saving over conventional aluminium. Here again, these grades were selected in cases where it was possible to optimise the trade-off between function, mass, cost and the required manufacturing processes. Some of them necessitated a new warm stamping process (approximately 250/300°C, compared with hot stamping which is closer to 900°C) but this was compatible with existing stamp shop facilities.

Renault EOLAB

Renault EOLAB

All-aluminium circumferential chassis member

A combination of castings, sheet metal and profiles was chosen for EOLAB’s all-aluminium rear circumferential chassis member . Their use represented a good compromise between mass and body rigidity. Moreover, using the same material for this part of the shell was an attractive proposition in terms of thermal expansion. Indeed, body shells are exposed to temperatures of up to 180°C in the paint shop curing ovens and certain multi-material assemblies can have a negative impact on body shell’s geometry.

Advantage was also taken of the use of cast parts of varying strength to cover multiple functions, that is to say the use of large, one-piece components to replace a number of smaller parts. This made it possible to compensate for the technology’s additional cost compared with conventional stamping.

3. A magnesium roof weighing just 4.5kg

While using steel and aluminium for a car body is itself not usual, Renault went further down this path in the case of EOLAB by making use of magnesium, too. This metal is reputed for its light weight (density: 1.7), but it is also prone to corrosion which is why it has only been used for interior components until now. Some cars already feature magnesium but only for moulded parts made from magnesium powder (e.g. the majority of the market’s steering wheel armatures).

EOLAB breaks new ground in the automobile industry by using magnesium sheeting. Developed thanks to the expertise of the specialist supplier POSCO, this innovation permitted the production of bulky items such as the roof, cowl panel and parts of the seat frames. The advantage is obvious, since EOLAB’s roof tips the scales at just 4.5kg, compared with 10kg for an equivalent steel roof. (For further information, see appendix at the end of this document)

“Magnesium sheeting cannot be used for as wide a range of parts as steel, or even aluminium. However, where the compromise between function, mass, cost and manufacturing processes allows, there are spectacular savings to be achieved, especially as the manufacturing process is the same as it is for certain new grades of aluminium, i.e. warm stamping,” points out Vincent Desmalades, Deputy Project Leader in charge of Processes.

4. The contribution of polymers

In order to cover as many realistic solutions as possible to minimise EOLAB’s weight, the project team also took a look at polymers which have long been reputed for their benefits in this area.

From thermoset to thermoplastic resins

Assisted by university laboratories and specialist suppliers, the team behind EOLAB worked on a new family of thermoplastic resins which are easier than thermoset resins to recover at the end of the vehicle’s life cycle and consequently recycle.

The demonstration car’s front, rear and central floor pans, B pillars and lower cross member are all made from hot-stamped composite thermoplastic, while the skins of the one-piece wings/bonnet assembly and doors are made from injection moulded thermoplastic. The type and proportion of the glass fibres mixed with these polymers vary as a function of the properties required for each end-use (e.g. longer fibres for structural components).

Reducing the weight of main assemblies

After attending to the body shell, EOLAB’s designers turned their focus to the car’s main assemblies which were all scrutinised with a view to saving weight. The brakes, steering, suspension, wheel and tyres were all looked at carefully to shave off kilogrammes without penalising their performance.

Renault EOLAB

Renault EOLAB

1. Lighter running gear

A vehicle’s running gear alone accounts for almost 20 percent of its weight (e.g. the Clio IV = 225kg). The most efficient solution involved replacing steel with aluminium for a significant number of heavy parts, such as the subframe, which has shed 5.3kg compared to that of the Clio IV (14kg), suspension arms (1.8kg saved), hub carriers (5kg saved) and rear arms (9kg saved).

Substantial savings were achieved in this way, but EOLAB’s designers didn’t hesitate to explore other, more complex solutions. For example, they took a totally different approach to the architecture’s resistance to head-on impacts while maintaining the same overall level of safety performance. Normally, programmed chassis deformations affects three areas in an impact: the upper part of the chassis, the side members and the lower part of the chassis). In the case of EOLAB, the latter’s ‘add-ons’ were eliminated but this was compensated for by relocating and strengthening the side members. The resulting saving was between seven and eight kilos. “We also looked at making the springs from a glass fibre/thermoset plastic composite, which would have produced a saving of three kilograms. Using a different composite for the rear beam would have saved another three kilos or so, too,” notes Laurent Taupin.

2. Revised brake system

One might be forgiven for thinking that brake systems cannot make any sort of contribution to curbing CO2 emissions, yet they can. Indeed, reasonably big weight savings are to be made in this area. “EOLAB’s innovative brake system was developed in conjunction with Continental and points to the road down which Renault intends to go for its electric and hybrid vehicles in years to come,” says Laurent Taupin.  For the same stopping performance, work on the brake system yielded a total saving of 14.5kg.

No fewer than three advanced innovations were developed in association with Continental. The most visible contribution was to suppress disc rub, whereby the brake pads remain in contact with the discs even when there is no pressure on the pedal. This constant rubbing adds slightly to fuel consumption. In the case of EOLAB, the pads do not touch the discs whenever the driver’s foot is off the pedal. In addition to being beneficial to fuel consumption, this also extends pad life. To maintain the same speed of response, and even improve it, EOLAB’s system eliminates slack by moving the pads closer to the discs the instant the system detects that the driver intends to apply the brakes.

Furthermore, the system’s new brake control unit has replaced the control units of several previously distinct functions (ABS, ESP, emergency brake assist) while allowing decoupled braking which is indispensable when it comes to recovering braking energy to reduce energy consumption.

Meanwhile, the front brake discs have been lightened by combining steel and aluminium. The part of the discs in contact with the pads is made of steel, while the central part is made of aluminium. Also, since the body shell is lighter, it was possible to reduce the diameter of the discs for a total saving of 4.7kg.

A similar solution was employed for the rear drum brakes. The friction zone is still made of cast steel but the remainder of the drum is made of aluminium. The lighter rear brakes are more compact and equipped with more efficient bearings for a saving of 8.5kg.

Also in partnership with Continental, Renault took advantage of this arrangement to make the automatic parking brake act on the rear drums. This is more economical than the market’s existing system. Suppressing the manual mechanism (lever, cables, etc.) adds another 1.3kg to the total weight saving.

Renault EOLAB

Renault EOLAB

Shedding weight inside, too

1.  Lighter glass

The EOLAB team also secured appreciable savings by reviewing the car’s glazing. Work to reduce the glass’s weight led to collaboration with Saint Gobain Sekurit with the aim of saving between 30 and 50% compared with present-day standards.

The thickness of EOLAB’s windows was reduced to 3mm (1.5mm less than the current norm), equivalent to the thickness of a pencil line. The thin windscreen, the form of which is particularly aerodynamic, is an automobile industry first. The side windows use laminated glass (instead of tempered glass), while certain non-moving windows make use of polymers which have become a widespread material for optical glass, but are still rarely seen in the car industry.

Lastly, the rear screen uses polymères vernis (instead of tempered glass). This technology made it possible to produce a one-piece polymère verni screen that also incorporates the rear lights. This solution serves as an eloquent example of how different functions can be grouped together to not only save weight but also enhance aerodynamic performance.

Combined, these solutions brought the total weight of EOLAB’s windows down to 21kg, a 25% saving over a Clio (28kg). (For further information, see appendix at the end of this document).

“We could have settled for existing processes or recipes for EOLAB, but that wouldn’t have been in the spirit of the project which has allowed us to extend our expertise. It has also focused the attention of the whole company on the issue of minimising weight without losing sight of production-related realties,” explains Laurent Taupin.

2. Thinner, lighter seats

EOLAB’s seats also came under the scrutiny of the car’s designers who not only endeavoured to make these generally heavy items lighter but also sought to make them slimmer to free up extra room for rear passengers.

To achieve these two objectives, Renault called on the expertise of the seat specialist Faurecia:

  • The thickness and weight of the front seats was notably reduced by using different materials for the frames (steel, non-ferrous alloys such as aluminium, carbon fibre composite and magnesium). The result was a 35-percent saving over the seat frame of a conventional B-segment vehicle.
  • The cushion structure was optimised thanks to the use of a semi-rigid shaped trim and a compliant seat back. The resulting seat is 30 percent more compact, and this has freed up extra leg and knee room for rear passengers with no detriment to the comfort enjoyed by the front occupants who can still adjust the position of their seats.
  • The seat shells were lightened thanks to Faurecia’s Cover Carving technology which consists in embedding a rigid 3D pattern onto a textile support to enable the cover  to match the seat back’s forms as closely as possible. The use of this technology shaved 40 percent off the weight of the seat’s shell and provided rear passengers with three centimetres of extra room for their knees, legs and feet.

3. Using chemistry for lighter fittings

Close attention was paid to EOLAB’s smaller plastic fittings, such as the B-pillar trim. “These parts may only weigh a few hundred grams each, but they add up to about 10kg in the case of a production car if you include the boot lining,” points out Laurent Taupin.

With input from suppliers, Renault’s specialists looked at alternative ways to make these plastic parts. One idea was to replace solid parts less than 2.5mm thick with parts comprising an ultra-thin skin (1.8mm) and injected with foam which is lighter because it contains air bubbles. Thanks to the incorporation of ribbing, they boast the same structural strength. Until now, this technique has been restricted to large visible parts or parts that customers cannot see. In the case of EOLAB, the challenge was to find a process that would be appropriate for smaller visible parts.

Meanwhile, for EOLAB’s boot trim, Renault used another experimental technique which again uses a sandwich structure comprising a foam insert between the two outer surfaces. This sandwich is obtained by slightly opening the mould during production to allow the foam to spread.

Use of thinner fittings achieved a weight saving of between 20 and 30 percent.

4. Lighter than air

Meanwhile, plastics specialists took a close interest in the air intake ducts which are generally made of compact polypropylene and tip the scales at around 3kg. “Three kilos to channel airflow is too much,” believes Laurent Taupin.

The idea was therefore to replace this material with expanded polypropylene which is much lighter since its density is 0.06 compared with 0.96 in the case of compact polypropylene. However, if it had simply been a case of swapping one for the other, the switch would have been made a long time ago. In reality, it calls for duct walls that are five times thicker and that in turn means taking a fresh look at the car’s architecture. This is effectively what happened in the case of EOLAB and its ultra-light air ducts have been patented. They weigh just 700g, which is a spectacular saving of 2.3kg!


In addition to being lightweight and aerodynamically efficient, the EOLAB demonstration car goes even further in its bid to achieve ultra-low fuel consumption thanks to its 100%-Renault hybrid powertrain which is covered by more than 30 patents. This technology consists in combining a petrol internal combustion engine (ICE) with a compact electric motor. This solution permits 60km** of zero emission* motoring plus extended range thanks to the internal combustion engine. Importantly, it can be carried over to entry-level vehicles which are by definition a more affordable reality for a higher number of motorists. This technology will be incorporated in the range by 2020.

* No CO2 or other regulated polluting emissions during road use.

** Consumption, emissions and range data homologated in accordance with appropriate legislation.

Renault EOLAB

Renault EOLAB

A motor inside the clutch housing

In the case of the EOLAB prototype, the ICE part of the powertrain takes the form of a small three-cylinder 999cc petrol engine with a power output of 57kW (75hp) and peak torque of 95Nm. It is mated to a highly innovative clutch-less transmission based on a compact and economical three-speed gearbox which is sufficient to cover the vehicle’s speed range. This is a notable advantage compared with the majority of the market’s hybrid technologies which make use of CVT- or DCT-type transmissions (Continuous Variable Transmission, or Dual Clutch Transmission). These tend to be bulky, heavy and costly, and consequently ill-suited to small cars.

The chief feature of the concept lies in the clutch casing which houses a permanent magnet electric motor (axial flux discoid motor in the case of the prototype). This motor is compact and economical and covers the need for the availability of extra torque since it is capable of instantly delivering peak power of 50kW and 200Nm of torque.

Fed by a 6.7kWh battery, it is sufficiently big to power the car under electrical power. Here again, the war waged on the weight of the body shell made a great deal of sense inasmuch as a lighter car needs less energy to be moved forward. As a consequence, the battery can be both smaller and less expensive.

Gearshifts for electric and ICE modes

It is important to note that the first two ratios of the three-speed gearbox are mated to the electric motor, while the third ratio is linked to the ICE. These three ratios permit nine different combinations for the electric and hybrid modes combined. One of the concept’s major innovations is the fact that gearshifts do not necessitate the use of a clutch thanks to a specific control unit designed by Renault’s engineers.

A battery suited to hybrid use

EOLAB’s axial flux permanent magnet electric motor is powered by a 6.7kWh lithium-ion battery which differs from the batteries that equip Renault’s Z.E. range of electric vehicles. While electric vehicles are designed to store a high amount of energy because of the fundamental need to maximise the vehicle’s range, hybrid vehicles like EOLAB need to cover the same power requirement with a limited quantity of electrical energy. This entails using a different type of battery cell with a higher power/energy ratio.

The resulting battery pack is the fruit of active cooperation between the teams at Renault and the CEA who rose to the challenge of finding smart solutions to come up with a battery pack that is capable of storing a high amount of energy in a smaller volume, while at the same time minimising weight.

Z.E. Hybrid… One mode for weekday use, another for weekends

A choice of two modes.

  • The ‘weekday’ mode favours the use of electrical power for everyday journeys (e.g. from the home to the workplace) in order to get as close to zero tailpipe emissions* and zero fuel consumption* as possible. EOLAB’s range is sufficient to cover 60km* under electrical power. When this mode is selected, the car always pulls away under electrical power and the first gear allows speeds of up to 60/70kph to be reached. At faster speeds, the system automatically engages the second gear and continues to run on electricity alone up to 120kph. Beyond this speed, the hybrid system automatically calls on the internal combustion engine which drives through the third gear.
  • The ‘weekend’ mode combines both sources of power to permit longer travelling distances. Although the car still pulls away under electrical power, the internal combustion engine is engaged at a lower speed. The two power sources then combine, not only to use less energy but also to benefit from a real power boost thanks to the association of the ICE’s 90kW and the electric motor’s 50kW . In this mode, the battery charges under deceleration and braking (range saver function). The combination of the different gear ratios covers use up to the vehicle’s top speed in hybrid mode.

This is a major concept that shows a way forward for hybridisation. “Today, most of the market’s hybrid vehicles are higher segment cars with a price tag of more than €40,000. The solutions showcased by EOLAB are much more economical and enable hybrid technology to be used for smaller cars and on a much bigger scale. Our objective is to produce a car with two power sources for the price of one,” underlines Jean-Pierre Fouquet, Z.E. Hybrid Innovation Project Leader.

** Consumption, emissions and range data homologated in accordance with appropriate legislation.

* No CO2 or other regulated polluting emissions during road use.


HMIs in favour of low fuel consumption and motoring enjoyment

Although Renault’s first hybrid vehicle – EOLAB – is packed with technologies and innovations, it is still aimed at the brand’s core customers, so had to remain easy to use and intuitive. It was also developed in keeping with Renault’s Driving eco² philosophy. At the same time, its Human Machine Interfaces (HMI) go even further down the road of providing information in real time with a view to helping drivers to benefit from ultra-low fuel consumption.

Renault EOLAB

Renault EOLAB

Its development was guided by three factors:

  • Visualisation of EOLAB’s technological features: the EOLAB demonstration car is equipped with aerodynamic features like an active front spoiler and active flaps which deploy at speeds in excess of 70kph.
  • Intuitive: despite the car’s advanced technological content, the MMI was designed to be simple to use. “When a car targets a broad public, it is important that its use is easy to take on-board without having to read a manual that is dozens of pages long. In this respect, EOLAB follows the example set by R-Link which has received numerous accolades for its intuitive ease of use.”

When technology takes centre stage

Given that on-board active systems are not visible from inside the vehicle and are only triggered at speeds or more than 70kph, the driver may feel a certain degree of frustration. Renault has endeavoured to avoid this issue by incorporating a specific function into the multimedia tablet which enables all of these systems to be activated and displayed whilst the car is at a standstill. “When an EOLAB-derived production car sees the light of day, it will not only be purchased out of economic motivation. Customers will also be attracted by its environmental and technological benefits. They will therefore want a ‘quantifiable return’, and this type of function will meet that requirement. Renault is keen to demonstrate that it is possible to drive an ultra-economical car whilst at the same time enjoying the experience,” underlines Rémi Bastien.

Instrument panel and multimedia display

In practice, the Human Machine Interfaces (HMIs) have been divided between two principal areas: the instrument panel and a touch screen multimedia display situated in a central position on the dashboard.

  • Height-adjustable instrument panel:

The first original aspect is that this is not fixed. Courtesy of a mechanical arm, it moves in accordance with the height of the steering wheel that has been selected by the driver, in order to ensure optimum visibility.

Its content is spread across two digital displays the size of a smartphone: the one on the left provides all the technical information (speed, levels, conventional warnings), while right-hand side display is dedicated to the GPS. The upper part is utilised to display the image generated by the central rear-view camera. The lower part covers all of the multimedia system’s controls (radio, climate control, etc.).

  • A centrally-positioned touch screen display:
Renault EOLAB display

Renault EOLAB display

All of the other functions are to be found on the touch screen display, allowing for the dashboard layout to be simplified, in-keeping with the spirit of EOLAB’s uncluttered design. The screen of this 11-inch tablet is divided into two parts. For the first time in the automotive world, the tablet can be fitted either horizontally or vertically, with distinct display graphics for each position. “In the vertical position, the accent is placed upon the sharing of information, which is easily visible to the other passengers. In its horizontal position, the screen is brought closer to the driver, generating a ‘cockpit’ effect, whilst the display graphics becomes warmer and more colourful,” explains Patrick Lecharpy. This unprecedented horizontal and vertical duality required specific studies and research to ensure that the two positions were compatible with the vehicle’s safety features, most notably its airbags.

Renault EOLAB display

Renault EOLAB display

Another noteworthy point: “With EOLAB being a hybrid vehicle, the drive mode is visible in an informative and educational manner on the tablet by way of cloud-shaped symbols that are blue when EOLAB is powered by its electric motor and turn red when the internal combustion engine takes over. What’s more, the size of these clouds varies according to the quantity of energy available in each mode,” reveals Patrick Lecharpy, the project’s design manager.

Putting drivers in charge of their energy consumption

Generally speaking, with energy consumption being at the very heart of the EOLAB concept, significant attention was paid to the presentation of related data. “As this is Renault’s first hybrid vehicle and an ultra-economical car, we really wanted the Human Machine Interfaces to permit a comprehensive understanding of the parameters that influence consumption, in order to assist drivers as they learn how to drive more economically,” indicates Laurent Taupin.

As a result, when the car is moving, the central tablet displays a ‘radar-style’ graphic whose five branches represent the five principal factors affecting the vehicle’s consumption:

  • Acceleration/braking (driving style)
  • The car’s aerodynamics
  • The gradient
  • Tyre rolling resistance
  • Use of electrically-powered equipment (notably thermal comfort)

This graphic alters in real time according to the status of these five key parameters, thereby providing the driver with indications about how consumption may be improved in real time. “Today, after a fashion, the majority of the systems available in the market give drivers just raw information (current consumption, average consumption, etc.) that don’t really enable them to make any progress. Courtesy of this graphic, drivers now have at their disposal the necessary tools to take charge of their own consumption,” continues Jean-Pierre Fouquet, Z.E. Hybrid Innovations Project Leader.

Renault EOLAB

Renault EOLAB

Renault EOLAB

Renault EOLAB

Renault EOLAB

Renault EOLAB

Time for videos:

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28 responses to "Renault Unveils EOLAB Plug-In Hybrid (w/videos)"

  1. DaveMart says:

    Many thanks for the most comprehensive report on this I have seen to date, Mark.

    This is the sort of innovation that anoraks like me really find exciting.

    Personally I like the idea of lightweighting, and prefer building 955kg PHEVs to cars with huge and weighty battery packs.

    In terms of life time impact, the low weight of this means that CO2 emissions savings during production are going to be significant over a pure BEV which weighs a lot more.

    1. Lindsay Patten says:

      That depends on the emissions associated with the specific battery production. If the batteries are produced in a factory powered by non-emitting renewable energy, from materials produced with same, then maybe not so much.

      Once you remove fossil fuel use from the process, weight no longer correlates to emissions.

      1. DaveMart says:

        Extra weight correlates pretty well with energy consumed in manufacturing it for any given level of carbon intensity in manufacturing.

        It also correlates fairly strongly with energy used to move it around throughout its life.

        That is not to mention the huge amount of additional damage it does to anything it hits, as impact equals mass times velocity squared.

        1. Lindsay Patten says:

          Absolutely, but energy doesn’t necessarily correlate to carbon emissions. Use hydro, nuclear, wind or solar energy and weight no longer correlates with emissions.

          1. Lindsay Patten says:

            (And the world’s biggest manufacturer of electric cars with big batteries is building a battery factory that it plans to power with renewable zero-emission energy.)

            1. DaveMart says:

              No its not.
              Its a grid offset, which however worthy is a completely different matter.

              1. DaveMart says:

                And Tesla are not the world’s biggest manufacturer of electric cars.
                Nissan is.
                Tesla are the biggest users of electric batteries for transport, which is not the same thing.

                1. Lindsay Patten says:

                  Note that I said biggest manufacturer of “electric cars with big batteries” 🙂

                  In this case, what is the difference in emissions between net-zero energy and powering your factory with non-emitting renewable energy?

                  1. DaveMart says:

                    If it were the same thing, there would not be the unremitting efforts to confuse them.

                    Solar is a pretty good thing in the US grid, as there is a large load for air con during the day, especially in the summer.

                    So building out solar to match the annual consumption of the factory is no bad thing.

                    One thing which it is not, however, is running the factory on renewables.

                    For a start the solar arrays would need to be greatly oversized to provide adequate power in the winter, even at the latitude of Nevada.

                    Secondly unless the factory only operates one shift, a lot of the work will be outside the daylight.

                    At the moment there is no economic case in most of the US to store daytime power in batteries rather than using off-peak power.

                    It is true that up to 70% of the light duty vehicle fleet in the US could be run without substantial increase in generating capacity if they were charged off peak.

                    Since hydro and nuclear are already almost fully utilised that really means burning more fossil fuels, and lots of them, at night at existing power stations, which is great for their economics and lousy for emissions.

                    So off-setting is in no way the ‘same thing’ as running the factory on renewables.

                    I don’t know the sources of Nevada’s power, but if it is coal or gas for off peak then substantial quantities will still be used if the Tesla factory operates for more than one shift, which presumably they hope and intend to do to amortise the capital efficiently.

                    The Renault factory in contrast if it is in France or nearby can get its electricity from the French grid, which is 75% nuclear and available day and night!

                    1. Lindsay Patten says:

                      Nevada is 68% natural gas and 18% renewable (source: so I would think we can assume that any energy Tesla consumes from the grid will come from NG and that any energy they put on the grid will displace NG. If that’s the case then if they are net-zero energy they will contribute net-zero carbon emissions compared to if they weren’t operating a factory. No?

  2. David Murray says:

    Interesting.. So 6.7 Kwh battery pack is pretty similar to the Ford Energi products.. although with the lighter and more aerodynamic car, I’m guessing real-world EV range somewhere around 25 miles. Which is a sweet spot for PHEVs, I think.

    I keep waiting for Nissan to come out with a PHEV. I am really baffled that they have not jumped on the PHEV bandwagon.

    1. DaveMart says:

      Renault sure make prettier cars than their stablemate!

      Both the Zoe and this knock spots off a certain frog-eyed car!

    2. JRMW says:

      “I’m guessing real-world EV range somewhere around 25 miles. Which is a sweet spot for PHEVs, I think”

      Could you expand on this? Do you mean because of the added cost per extra EV range or something?

      my bare bones optimum real world EV range would be 60 miles.

      My rationale (yes, I know I’m pulling numbers out of my bum):

      95% of Americans drive less than 30 miles per day. It would be great to have this all be powered by battery, with the range extender to kick in after this.

      The real range will of course be affected by
      -battery degradation over time
      -only charging to 80%
      -winter and hot summers

      so conservatively:
      30 miles / 0.8 (for degradation) / 0.8 (for 80% charge) / 0.8 (for winter/heat losses, conservative)

      30/0.8/0.8/0.8 = 60 miles.

      This way a person in a 5-10 year old PHEV could still drive 30 miles in winter on an 80% charge.

      it may be more expensive, but BMW i3 already has 72 miles of range and an Range extender, so clearly is possible today.

      1. David Murray says:

        OK, I’ll expand on that. A lot of it has to do simply with cost. When dealing with a PHEV that has no range limitation like a BEV, there are diminishing returns for each additional EV mile of range you add to it.

        As a driver, obviously I prefer more EV range. But I’ll be satisfied as long as the car has enough range to get me to work and back. Millions of people live close enough to work that 25 miles of range would handle that. But with workplace charging becoming more common, that could easily double a person’s daily driving range to 50 miles.

        I definitely think there is a market for cars like the Volt and i3 that are really extended-range electric vehicles. But I’d like to see all of the hybrid cars currently on the market be upgraded with a 6.7 Kwh of battery so they could have 20+ miles of EV range with only minimal cost increase over the existing hybrid.

        1. JRMW says:

          I agree with you.

          I’m hoping that in 5-10 years batteries will be cheap enough that it’s not such a limiting factor.
          Kind of like what happened to Mobile Phones from 1990 to 2000 and SmartPhones from 2007 to present.

          I know I’m unnecessarily hard on these car guys. Then again it’s clear that we have to be hard on them, otherwise they pull a Toyota and bash BEVs while pushing old technology.

          I wouldn’t have believed it if you told me in 2004 that we’d have affordable BEV and PHEVs in 2014.
          I want to be equally surprised at how far things have come in 2024!

  3. Max says:

    “Innovative patented clutchless 3-gear transmission“

    Renault, it’s no longer cool to have automotive patents. Get with the programme 😛

  4. Anon says:

    The hyper-extended A pillar that merges into the sides of the hood, bothers me greatly. It’s interesting to note that the interior picture, looking out, was taken low and back inside the cabin, so you didn’t see the horse blinders that such a forward projection would create for the driver and front passenger…

    I want to see an honest photo or video or review, of someone (independent of Renault) driving this thing, and trying to make a left turn, etc..

    1. DaveMart says:

      Its a concept car, showcasing various near production ready technologies, not a prototype production vehicle.

      1. DaveMart says:

        How wrong could I be!
        They’ve built a driveable prototype, which drives rather well.
        See below.

  5. Cavaron says:

    While sub 1000kg cars which fulfill todays safety standards are great, 66km AER isn’t. I have seen the Ampera(Volt) doing 80km easily on one charge. And they need 10 years to get less?
    I would prefere they optimise production related energy needs (like plants with solar and wind farms) first. Should be achievable much faster.

    1. JRMW says:


      it’s even worse than you think.

      The BMW i3 REX gets 72 MILES (115 km) AER… today.

      Proposing half the range 10 years out is ludicrous, unless this thing costs 1/4 the BMW’s price in 2014 dollars.

      It’d be like a company proposing a 32 to 64 GB phone for 2024, when today’s phones have 128GB

      1. DaveMart says:

        Its designed for and will be sold in Europe.
        The pack is optimal for the vast majority of commutes there.
        A bigger battery would simply mean lugging around more weight on most commutes, and when you are going on a longer run it is way, way more efficient than the Volt.

        It would be pretty foolish to optimise a car for American driving when you are selling it in Europe.

        There is no such thing as one ‘best way of doing things’, you always have to ask: ‘Best for what?’

        1. JRMW says:

          I agree with your point overall.

          Which is why I qualified my statement to say that the future Renault product would be welcome especially if it were 1/4 to 1/2 the price of a today’s BMW i3 (inflation adjusted)

          But I can’t imagine many would be excited if a new medium to high priced product was released in 2020-2024 that had specs worse than products available in 2014 (If released today it would be a different story).

          You already see grumbling in the PHEV and EV world about the lack of significant increased range from 2011 to present.

          We see this dynamic today, with Toyota’s pathetic 11 mile AER Plug in Prius. Despite those pathetic stats, people buy it.
          But you also see that the Volt outsells the PiP, as well as the Focus and the Cmax in large part due to their crappy ranges. This is all the more significant because in general people prefer Toyota and Ford to Chevy.

          Using the phone analogy: Many people don’t need a 32 to 128 GB phone. thus, even today Apple sells 16 GB phones. And I’m sure that somebody sells a 1 to 5 GB phone somewhere in the world, especially where data is expensive (like less developed Asian and African countries).

          I welcome as many different models with different abilities, styles, prices as possible to give consumers EV choice. Clearly these low performance products serve a purpose and have a place at the table. I just don’t think they generate excitement

          1. DaveMart says:

            Personally I like optimisation, and tools which are suited to the job.

            The thought of paying for and lugging around more battery than I would need for day to day running around is a turn off for me, not a turn on, and I have zero desire to manoeuvre a 4,000 lbs electric dinosaur around!

            If I lived in the US, other than in SF or NY, the case would be completely different, and a far bigger car would be attractive.

            Thinking about it, this will not really be suitable for me, as I am an old boy, and getting in and out of a low slung car is not easy, even when I am not wearing a skirt! 🙂

            However another Renault is looking increasingly likely to me in a few years.

            1. JRMW says:


              I can see I’m more of an optimist than you.

              My hope is that battery sizes will be 1/4 the size they are today in 2024.
              This would allow double today’s range in 1/2 the weight/size! Similar to the fact that today’s iPhone has FAR more stuff in a far smaller package than the original iPod.

              But as I said above, I do foresee multiple battery size options for each given car in the near future.

              I’m like you on the BEV side. I have no need/want for a 500 mile AER range, even in 2024. I’d be happy with 300 miles for an AWD SUV, and 150 miles for the AWD sedan

              And I doubt I’d really want more than a 100-150 mile AER PHEV either.

              as for getting in/out of the car: sounds like we need to get you some bionic knees with an AER of about 2-3 feet?

              1. DaveMart says:

                I try to hope for the best, but I certainly don’t count on it.

                BEVs are becoming less and less appealing to me.

                At the top end the dream is to have monsters, carrying one or two people most of the time but capable of 7, hurtling to 60mph in less then 5 seconds when most drivers can’t drive a car which does 0-60 in ten seconds safely.

                At the bottom end at, say , $100kwh, which is pretty difficult to get below as you start hitting material cost limits, you have a car with maybe 50kwh for something half way adequate, and it would indeed be half way adequate, as road trips of a few hundred miles which are routine today would be a nightmare.

                They also require a charging infrastructure away from home which costs a fortune per kwh however you cut it, to have any reasonably timely access.

                I like VW’s plans, PHEVs for now, and maybe fuel cells to replace ICE eventually.

                It would only require a couple of hundred hydrogen stations to provide power on main routes for the UK, and the cost per mile driven on hydrogen is way lower than away from home charging.

                If I want to be a technical optimist, then higher temperature fuel cells would mean that neither hydrogen fuel stations nor expensive hydrogen tanks on cars would be needed, and cars could be really light weight.

                Still on the light weight theme, it looks increasingly likely that on major roads we will be able to provide through the road charging, so obviating the need for big batteries.

                I am just not a fan of the huge, 100kwh plus battery packs that are really needed to provide real on the road convenience, and reckon that we can do a good job with ~10kwh and new technologies such as hydrogen, or HT fuel cell, or through the road charging as they become available.

                All of them are as likely as the very powerful and cheap batteries you envisage.

  6. DaveMart says:

    Top Gear Drives it!

    ‘Because of the reduced area, the body is low. The front seats are further forward than usual, and the engine is inclined backward as it is in the Twingo. The windscreen is thin to save weight, and fairly upright, which again reduces the glass’s area and weight. To disguise this, strongly raked false blades sit proud of the A-pillars. These don’t have a structural or aero role, but they show how the designers wanted to make the car look seductive as well as perform well.

    This low position makes the car feel sporty when you drive it. And the light, sparse seats are comfy. Mounted to the steering column are phone-sized screens showing speed and car info on the left and navigation on the right. The main central tablet shows all sorts of graphics for how you’re using energy. The rear-views have their own permanent screen area, as the car has lipstick cams instead of mirrors. Mirrors, after all, are ugly, heavy and draggy.

    You’ve got an electric parking brake. This is a neat example of the depth of joined-up thinking throughout the car. An EPB is lighter than a handbrake. But they went further: instead of a mechanical steering lock, the car unlocks itself by releasing the EPB when the key is present. There’s no need for a steering lock, so the steering column needs less reinforcement and can be lighter.

    A shiny, drilled knob the size of half a golf ball is marked for PNDR. OK, let’s touch the starter button and turn to D. Eolab has a ‘weekday’ mode where it emphasises driving by electricity as it assumes you’re commuting. Range is 40 miles, and top speed 75mph, before the engine starts. But we’re in ‘weekend’ mode, which lets the engine and electric power combine for better performance. Top speed is limited to 100mph, 0-62mph is 9.0 seconds.

    It always moves away electrically. It’s silent, smooth, responsive and as clean-feeling as EVs always are. Then the petrol engine starts at about 25mph. Because you’re already rolling, it chugs to life unobtrusively. Whatever you do with the accelerator, it stays running as long as you don’t drop below that speed.

    The patent transmission has just three gear ratios and no clutch. One gear set is driven by the engine, the other two by the e-motor, and they’re brought into use in various combinations. This means the car can effectively change gear between four ‘gears’ (not just three) with the engine running, and the engineers say it should feel as smooth as a double-clutch. At the moment it doesn’t – there’s a notable pause, like an early single-clutch flappy-paddle. Anyway, it’s a lively enough little car, and easily feels like it can make the claimed 0-62 in 9.0 seconds.’

    1. DaveMart says:

      Heck, I’ve got to quote the rest:

      ‘Usually, concept cars are far too precious and fragile for proper driving. Not this one. It’s actually a ‘prototype’. They have another pristine non-runner for the Paris show itself. Although that doesn’t make this one any less valuable. What the heck – the engineer drives pretty briskly around Renault’s corner-rich test track, and seems happy for me to do the same. It’s a car that works.

      It can be chucked into bends without a care, and finds about as much grip as a decent supermini, despite the skinny aero tyres. Again, that’s its lightness paying off. It rolls a bit but you feel quite racy sat down low. The power steering feels unnatural going gently but actually gets livelier when you’re cornering hard, so the fundamentals are right.

      Like any energy-conscious hybrid, the Eolab harvests energy by electric regeneration when you brake. The pedal isn’t mechanically linked to the brakes, so the blending of regeneration and friction is determined by computer. The pedal needs more calibration: it’s grabby. But it stops you.

      We got to the test laps via a potholed farm track. Which went to prove the ride is supple and the body feels impressively tight and rigid.

      Renault insists most of the innovations won’t be too costly. For instance, the lightweight body might cost more, but it allows for a simple, cheap n/a engine and a small battery at just 6.7kWh. Brakes, suspension, steering, cooling and exhaust are all reduced too.

      But the main thing is, it drives like a normal car. It looks rather better than that. If this is the supermini of the next generation, we’re in.’

      I love it!

      Thirty years ago I had a Renault 5, which leant on its side round bends, but never, ever, lost grip!
      None of that hard-arsed German ride on a PROPER French car!

      This sounds like my next motor, if I can hang on a couple of years more than usual.