Community Research and Development Information Service - CORDIS

  • European Commission
  • Projects and Results
  • Periodic Reporting for period 1 - EP TENDER (An innovative range extending service for Electric Vehicles (EV), based on a modular range extender, available for on demand rental, and attached occasionally to the EV for long distance trips)

EP TENDER Report Summary

Project ID: 684085

Periodic Reporting for period 1 - EP TENDER (An innovative range extending service for Electric Vehicles (EV), based on a modular range extender, available for on demand rental, and attached occasionally to the EV for long distance trips)

Reporting period: 2015-07-01 to 2016-03-31

Summary of the context and overall objectives of the project

EP Tender helps electric cars go the distance

When someone is thinking of buying an electric vehicle, one consideration is how far he or she can go before recharging. The EP Tender project is developing a modular power system for long journeys with fewer stops, encouraging wider use of electric cars. Trials begin in summer 2016.

Electric vehicles can be a great choice for the environment and our energy security. A snap-on range-extender from the EP Tender project could encourage more car buyers to make that choice.
Most affordable low- to mid-range electric cars can do a day’s driving – about 100 km – before their battery runs out. But for longer journeys, regular recharging can add hours to travel time. The project’s trailer-based generator system – the tender – can add another 400km before drivers need to refuel, making electric cars a more versatile, more attractive purchase.
With the tender, drivers can also take their cars to areas where recharging facilities are still developing, further supporting electric vehicle uptake. To minimise their use cost and environmental impact – and maximise their convenience for users – the tenders will be distributed through a rental network when they are ready for launch.
Added power
About 98 % of average daily car travel is within the range of a standard electric car, according to published car use research. But the remaining 2 % of journeys can only be done conveniently if drivers use another car or if they install either a permanent range-extender or a large battery, both of which are expensive and heavy.
This is a definite barrier to building a market for greener cars, and get them become the choice of the majority, without unsustainable government subsidies.
EP Tender consists of energy modules that can be towed behind an electric car, adding in electricity so that long journeys become as convenient as they are using a petrol or diesel vehicle. These range extending tenders deliver electricity through a 400V power line, while a small computing device (a CAN bus) connects to the car’s electronics system to regulate the inflow of power. The tenders also contain a globally patented self-steering feature for smooth reversing, adding to their stability and proven crash resistance.
The current version of the tender generates power with a combustion engine and a 35-litre tank – the same size as the engine of a small car. Because electric cars can recharge overnight, when the often windier weather allows 100 % recharging from renewables, an electric vehicle combined with an EP Tender would use one tenth of the fossil fuel of a standard petrol or diesel car for typical car use. As technology evolves, the tenders could contain a large battery or fuel cell, for even greater sustainability. EVs will thus become omni-hybrid on demand, and will benefit from future technical progress on energy storage, without having to replace the whole car!
2030 vision
We expect that in 2030, vehicles will be clean, connected, autonomous and lean. These “transport modules” will carry enough energy for daily usage. But when reaching the motorway for long distance [autonomous] trips, an energy module will automatically attach to the vehicle and deliver the add-on required energy. The Tenders will commute on motorways and deliver a large scale range extending service to many EVs.
Analogy with mobile phones
Would you carry a much heavier and more expensive phone everyday just for occasional peak usage? (although it would be technically easy to manufacture). We all take a charger, or an external battery when traveling. And whenever battery technology makes progress, it’s for the benefit of size, weight and cost. We believe the same reasoning applies mutatis mutandis to electric vehicles.

Three conditions
Trailer are often seen as hazardous, and inconvenient. Our market research has confirmed this by highlighting three conditions for success: safety, convenience and availability.
We have embedded from the very beginning these requirements into our project:
• Passive safety: no fuel leakage when hit from the back at 80km/h by a 1 400 kg vehicle. The Tenders are even acting as a crash box by absorbing close to a third of the energy of the crash!
• Active safety: pass the Moose test without creating unbalance in the car or overturn the Tender. The Tender are overall hardly noticeable by the driver on road tests.
• Convenience: Self steering when backing (no knife jacking), attaching to the EVs in one go, backing radars, automatic power management
• Availability: on line booking of the Tenders and 50km mesh for the rental network
Overall objective
The overall objective of this project is to develop a small fleet of pre-series Tenders and make a field test with the trial of five tenders and up to 50 electric cars. This field test which will start in France in summer 2016 with key commercial clients and private individuals. EP Tender will also look for industrial partners toward the end of 2016, for manufacturing and financial support.
Should the field tests be positive, our company plans to develop a tender rental network – the Tender’Lib network – in Europe, North America and China.
Our market research (available on suggests the Tenders could reach 20-40 % of electric vehicle owners, which could represent up to 2 % of the overall car market by 2030 and reach a turnover of €6 million for the company in 2020.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

This report is describing the work performed between July 1st 2015 and March 31st 2016.
We started the project with the results of a demonstrator and the draft of a new design.
Our demonstrator had successfully proven the concept of a modular range extending solution, with a lightweight and compact design, and suitable user convenience.
But there was a number of weaknesses in this early design, and we discovered further required enhancements during the course the period 1 of our project.
Our deliverables are structured around six operational work packages:
WP1: Tender platform tuning and manufacturing of a preseries for the field test in France and demos elsewhere.
WP2: Developing and testing the embedded electronics for controlling the power and all functions of the Tenders
WP3: Developing, testing and mounting suitable equipment on the field test vehicles, including their homologation where required
WP4: Implementing a car sharing platform for EP Tender
WP5: Operating the field test, and modelling of the rental network.
WP 6: Dissemination

The original planning was to start the field test before the end of Period 1.
Progress report
An EP Tender is essentially half a car: apart from the seats, the rear wheels and the gearbox, it carries about all functions you can find in a passenger vehicle, plus the hitch. So it is a quite complex system, with considerable interdependency between components themselves and with software. This was a steep learning curve!
Our project is based as much as possible on carry over components, and calls on external expertise through subcontracting in order to reduce risks and reuse the experience accumulated by the market.
This first period is very successful as it is demonstrating that we are on the right track. Our design is proving capable of matching the technical constraints we had assigned: safety and convenience. As compared to the demonstrator design, it is also much simpler to manufacture, easier to maintain and the components are cheaper, notably with a bearing less alternator and no requirement for an inverter.
We faced difficulties, which caused delays, but no significant cost overruns thanks to our lean and low fixed costs structure.
Late delivery of key components:
• the final assembly and the testing of the first prototype started 2 months later than hoped due to the late delivery of the first electric machine caused by the workload of our provider.
• The delivery of the internal combustion engines took place 6 months later than planned, as these engines are not imported in Europe, and our provider’s internal procedures were unexpectedly complex and long.
Tailor made components were generally delivered late, which was compounded by the frequent need for corrections of minors or more significant defects on the initial prototypes.
Even “off the shelf” components might take up to 6 weeks to deliver, like for example 400V automotive connectors, or simply hitch components which have run out of stock.
Work performed
One test Tender is operational and has been tested on long distances. We still have issues on the original exhaust manifold which is too fragile for our usage. We have made the decision to build a stronger tailor made manifold to solve this issue.
7 more Tenders are ready for the mounting of the electric harness, and the body which were not yet ready at the end of period 1.
The self-steering system had to be enhanced by using hydraulic cylinders instead of cables, with major benefits on maintenance and dynamic road handling (damping effect on sway).
Passive safety (crash test), dynamic safety (moose test), EMC (electromagnetic compatibility) have been passed successfully, or with requirements for minor enhancements in the case of EMC.
The NEDC fuel consumption is expected below 1l/100km, or 20g Co2/km. The actual consumption will of course vary with the percentage of full electric driving.
Our concept of a simple pmsm bearing less and air cooled alternator, mounted directly on the engine case, with two speed control through a dual winding, is working very satisfactorily.
We have also developed a new hitch system, based on commercially available collar and receiver, for more convenience and easier homologation.
We have not yet obtained the unitary homologation of the Tenders, and the cars used for the field test. But we are making good progress and the ground work preparation has been achieved.
We have successfully developed the hardware and the software of the Tender Control Unit, as well as the user interface on a smartphone. We are about to implement a newer version which is integrated in an automotive packaging (for EMC compliance), includes the hardware for controlling our new hitch, and enhanced smartphone communication with Bluetooth.
We have equipped one Renault Kangoo with the tow bar and electric connections. 50 kits are being assembled to be mounted, once homologations are passed, on Renault Zoe and Kangoo.
We had to find a new provider, as our initial partner has withdrawn at the very end of 2015 as a result of new shareholders and a new strategy. At the closing of Period 1 we had established a simple demo ( with our new provider, and we are now actively working on the implementation of their solution.

We are not yet ready to start operating the field test, as we must finalise the mounting and testing of the preseries, and we have to get the unitary homologations for both the Tenders and part of the cars (Renault Zoe).
We have started the modelling of the rental network in order to anticipate properly the sizing and location of the rental points, as well as the refining of our business plan.
Dissemination is a key activity in preparation of our commercial activity. EP Tender has been shown on major TV channels like France 2, BFM TV (generated 2 000 visitors on our web site in three days), and Euro News. We have exhibited and presented scientific papers at major events: Geneva Motor Show (with about 9 000 visitors on our booth), EEVC 2015, TRA2016, EVs29 (next June). We had 14 000 unique visitors on our web site, and 53 000 page views during Period 1. There have also been numerous articles commenting on EP Tender on the web. We are making extensive use of social networks like Facebook, LinkedIn, Twitter and EV forums, in order to keep regularly updated our large community of followers.
EP Tender has established many very promising professional contacts with OEMS, tier one equipment makers, fleet managers, craftsmen and individuals at all these events. The feedback we receive is excellent and our prospective clients are impatient to see the Tender’Lib rental network in operation.
Main results so far
We have built very strong foundations, with a platform which keeps on its promise for safety, convenience and availability through an on demand rental network.
We had to deal with many technical and planning issues, but we managed to overcome them, or have plans for doing so.
The EV market is evolving in our favor with more plug-in hybrid solutions, charging infrastructure and energy density in batteries. EV are a must and have become desirable. There remains the unescapable truth that the marginal cost and impact of satisfying the marginal 2% long distance requirements is disproportionate, contrary to an add-on modular solution. The continuous development of the functional economy is also supportive of our business model.
The energy module concept of EP Tender is getting real, and is gaining momentum in the EV stakeholder community.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

I) Introduction

The state of the art of EVs has made very strong progress over the last 5 years, with the launch of the Nissan Leaf, Renault Zoe, and the Tesla Model S.
But in spite of steady battery progress (5 to 8% per annum), the challenge remains entire regarding expanding the peak range of EVs at an affordable cost.
BMW is offering an optional range extender on the i3, but this is a rare exception. None of the many range extender projects launched by tier one equipment makers has made it to the industrialization phase.
The final challenge is that trailers are seen as hazardous and inconvenient!
We have chosen to select those challenges and contribute to the progress the state of the art on the following:
• Provide long distance range to EVs at a low marginal cost, and in a convenient way, through the on demand renting of energy modules
• Develop a low cost range extender, based on existing series production components
• Develop a light trailer which is safe and convenient to use
By achieving these targets, EP Tender enables a much wider adoption of soft mobility (EVs) by the general public with very positive environmental consequences, and develops a new kind industrial and service activity in Europe with a global market reach.
II) Progress in Period 1
Our project is built through a bottom-up approach, starting from the development and tuning of the pre-series platform and range extender, and in a second stage to implement a field test involving both fleets users and private customers.
a) Developing a light trailer which is safe and convenient to use:
Until now, attaching a trailer to a vehicle required mounting the collar on the vehicle, touching dirty parts, and to knee on the ground to connect the plug. Backing manoeuvers was also very difficult, particularly when the trailer is hard to see by the driver and very short in length.
EP Tender revolutionizes both aspects as can be seen from this video: . Attaching the trailer to the vehicle is done in one go, and backing maneuvers are seamless. We have also mounted backing radars on the Tenders, in order to signal obstacles to the driver. EP tender’s self steering system is protected by patent WO2013132468.
Trailers are not subject to crash test regulations or dynamic handling tests like the Moose test. It is not advisable to make sudden changes of direction when towing a trailer!
EP Tender has been subjected to the US FMVSS301R simulated crash test. This crash test consists at hitting a vehicle from the back with a 1400kg moving barrier at 80 km/h. This test has demonstrated the efficiency of our patent EP2666704 for protecting the fuel tank and ensuring passive safety of the passengers. The Tender even absorbs 31% of the energy absorbed by the vehicles, thus acting as a crash box, further protecting the passengers.
We have tested EP Tender at high speed on a road track: the behavior is totally neutral and the driver could hardly notice any difference from the towing vehicle. We have also done the Moose test on ISO and VDA conditions, with very satisfactory initial results: the ESP is acting efficiently and the car remains under control. We have identified areas of improvement which will be implemented in Period2.
We have now demonstrated that light trailers can be both safe and convenient to use, and we hope to enhance further our results in this area.
b) Developing a low cost range extender, based on existing series production components:
Many truly remarkable range extender prototypes have been developed by major players in the automotive industry. But unfortunately none is currently available to third parties, and only BMW has industrialised theirs. So we had to develop our own solution.
We chose a lightweight, simple but state of the art combustion engine from a low cost car, and a permanent magnet synchronous alternator used for generators or small wind mills. The two windings of the generators are set to they produce 360 V at 4500 rpm when in parallel, or 360V at 2250 rpm when in series. The vehicle’s battery is thus setting the generator and engine speed (quasi constant tension), and we control the power via the engine’s throttle. The result is a low cost range extender, with two nominal speeds. We hope the industry will come with fully packaged sets with optimized endurance and fuel consumption, as we have not focused on these two areas at this stage.
c) Providing long distance range to EVs at a low marginal cost, and in a convenient way, through the on demand renting of energy modules:
The rental network of the Tenders is not operational yet, as we are assembling the Tenders and mounting the first pre-series kits on test vehicles.
The rental platform is being setup from the basis of an existing car sharing service provider.
We have identified key launch clients (fleets and individuals), as well as target rental points.
Ahead of the results of the field test which will be conducted in Period 2, market research tells us that 3.7 % of car buyers would be “definitely” incentivized to purchase an EV if the EP Tender range extending service is available, and 20% of current EV owners would “definitely” become clients (plus 21% “probably”). These results show that EP Tender is a strong enabler of EV adoption by the public, by providing long distance range at an affordable marginal cost.
Current state of the art consists at either ever increasing battery capacity of electric vehicles, to the expense of their cost, weight and size, or building plug-in hybrid solutions with the same unwanted consequence. As classic internal combustion engine vehicles remain highly competitive, significant fiscal incentives are required to boost demand to levels which are still much too low.
EP Tender allows to reach an optimal (and affordable) solution for everyday usage, plus an on optimal (and affordable!) add-on solution for peak usage. With the ability to match closely on each trip the available infrastructure, as well as technical progress over time, without replacing the whole vehicle.

III) Socio-economic impact

We are just launching a comparative life cycle analysis of EP Tender vs other powertrain architectures: internal combustion engine, hybrid, plug in hybrid and very large battery EV. This analysis will give indications on the potential environmental benefits of keeping the battery at a reasonable level, and using an EP Tender occasionally.
The daily use of full EVs will also provide local environmental benefits in large cities, as well as noise reduction.
The expected reduction in fossil fuel consumption (and tailpipe emissions) is a factor of 1 to 10, assuming 10% of the kilometers are achieved on long distance trips.
The EP Tender staff has increased from 5 to 7 at the end of Period 1, and is planned to increase to 20 by 2018.
We target a turnover of 6 m€ in 2020, with 16 000 clients and 1 400 Tenders in operation.
European OEMs and equipment makers are at the forefront of EV technology and will benefit from EP Tender’s development.

Related information

Follow us on: RSS Facebook Twitter YouTube Managed by the EU Publications Office Top