Energy efficiency attractive for heavy utility vehicles

Monday, November 18, 2013

Energy usage surveys and energy improvement of hydraulic systems are some of the topics that attract the interest of utility vehicle manufacturers.

Anders GrauersAnders Grauers, Chalmers, driveline expert within SHC, was recently invited to talk about driveline solutions at a workshop on Energy efficiency, arranged by The Association of Heavy Vehicles (Tunga fordon). The association is a cluster of heavy utility vehicle manufacturers in southern Sweden, active within the sectors of forestry, construction and heavy material handling.

Did you arrive at any interesting results at the workshop?
-Yes, one interesting result was that a change in the driveline which can increase the vehicle productivity possesses a greater value than just that of reduced fuel consumption. As a rule, increased productivity will lead to lower fuel consumption for each task performed by the machine. Hence, it could be of interest to investigate if hybridization can increase the productivity, e.g. by increased precision and quicker driveline control.

What did you talk about?
-I talked about the reasons for hybridization, fuel saving being one important motive. I also described how hybridization will affect the vehicle in many different ways, and showed ways to reason in order to determine which solution is the most adequate for a certain vehicle. To inspire to think freely around different hybridization aspects, I provided examples from various types of vehicles where the solutions and reasons for hybridization vary. Finally, I pointed out that there is a difference between what is profitable and requested today, and the demands that will be put on the vehicles in the future.

What are the differences between drivelines for utility vehicles and road vehicles?
-The differences between different types of utility vehicles are often at least as big as the differences between road vehicles and utility vehicles. It is not easy to speak of utility vehicles as a group. However, one significant difference is that the energy used for propulsion is generally just a fraction of the total energy consumption of the utility vehicle, which often makes it more important to study energy improvements in other parts of the vehicle than the propulsion system.

Could you say something more specifically about the types of vehicles manufactured by the participants of Heavy vehicles?
-One important factor is that the utility vehicles in question are produced in small series. Therefore it is not reasonable to develop special components for just one type of vehicle. The required components must be suitable for a number of different vehicles.

Can any of the studies made within SHC be of use for The Association of Heavy Vehicles?
-Yes, at the workshop there was a great interest for surveying the energy consumption in the vehicles in order to find out the potentials for fuel saving with different solutions. Several of the energy study methods made within SHC could be useful for such an analysis.

What kind of questions did the workshop participants ask you?
-They asked about how to hybridize heavy road vehicles, and they were curious about the differences and similarities between hybridization of “their” vehicles and traditional trucks and buses. In the part of the workshop where future projects were discussed, there was a lot of talking about the hydraulic systems and whether it is possible to regenerate energy from them in an efficient way.

How far do you think they have come towards hybridization?
-Of course there are big differences between the companies, where some are working with, or have made investigations into the possibilities of hybridization, while others only just have asked themselves what it would mean for them. It is also important to understand that these companies are aiming to present vehicles with good properties at an attractive price. This means that hybridization is not a goal in itself, but one of many ways to produce a cost effective vehicle.

The workshop Energy efficiency was part of a project in cooperation with Chalmers Energy Initiative.

The Association of Heavy Vehicles (Tunga fordon) is hosted by SP Sveriges Tekniska Forskningsinstitut. Participants: Volvo CE, SP Maskiner, Svetruck, Semcon, Ljungby Maskin, Gremo, Cargotec, Alucrom, Dasa Control Systems, Kärcher-Belos, Fogmaker International, Rottne Industri AB

Text: Emilia Lundgren
Photo: Oscar Mattson