Although Renault Trucks has been leading the market in terms of fuel saving solutions for many years, particularly with the Premium Long Distance, it is still pursuing its research into new ways of reducing consumption with unflagging determination. This is clearly demonstrated by the RENOTER research project, designed to study the opportunities of recovering the heat found in exhaust gases (otherwise lost) and transforming it into electrical energy by the use of thermoelectricity. Scheduled to last three years, the programme will be coming to an end in October 2011. With this initiative, Renault Trucks is making a proactive commitment to researching and developing new systems designed to reduce its vehicles' fuel consumption even further.
A market leader in the field of fuel reduction, Renault Trucks is heavily involved in Research and Development projects which enable it to study and test all technical possibilities that can lead to making even deeper cuts in consumption. One of these is examining how thermoelectricity could be used to deliver fuel savings. RENOTER refers to "Engine heat recovery by thermoelectric power generation," explains Luc Aixala, an engineer with Renault Trucks and the project's manager. "It works on a very straightforward principle, with the heat energy from the exhaust being recovered and converted into electrical energy. This means the alternator does not have to work so hard and therefore, uses less fuel." The transformation of heat into electricity is achieved via an ad hoc exchanger incorporated into the exhaust line and equipped with small terminals made of thermoelectric material. The challenge lies in finding the most efficient, reliable and inexpensive components for this heat exchanger. Because this is of course a research project aimed at finding a solution to be used in manufacturing, with all the conditions in terms of component cost and availability that implies. "We want to find a system which is efficient and reliable," insists Luc Aixala, "with thermo-electrical materials which are readily available on the market and as inexpensive as possible, such as silicon, magnesium or manganese."
The RENOTER research programme began in 2008 and is due to finish in October 2011. So far, research has shown initial savings to be in the region of 1 kW, which would mean a 1% reduction in consumption under actual operating conditions.
Only the final results, and those of other projects being carried out in parallel using other energy recovery techniques, will decide whether this system is actually incorporated into production vehicles.
The RENOTER Project has obtained official recognition from the LUTB (Lyon Urban Truck and Bus) and Mov’eo competitive clusters. It has a budget of €4.5 million over three years, half of which is financed by public funds (DGCIS) and involves three university laboratories (Caen, Montpellier and Nancy) as well as Renault Trucks, Renault, Valeo, Sherpa Engineering and Nexter Systems.