Continuing just-auto’s series of interviews with tier one suppliers, Matthew Beecham spoke to Roland Priesemuth, Vice President Business Development, Denso Thermal Europe Centre about the key market drivers for climate control technologies.

As we understand it, the trend in the auto air conditioning market is moving from manually-adjust air conditioning, through semi-automatic, to fully automatic adjustment to fully automatic dual zone (for front seat passengers) to four zone multi-zone control. Is that correct?

As Denso we support our customers with any kind of technology request for the air conditioning systems for their vehicles. It is correct that in the last couple of years technologies such as multi-zone control, which have been used primarily in premium segments, are also applied for midsize and small cars. Automatic air conditioning systems allow drivers to solely concentrate on the driving operations of the vehicle. By measuring sunload, outside temperature and several other important ambient conditions, as well as the operating boundaries of the vehicle, the automatic air conditioning system controls the temperature and airspeed for the occupants. A well balanced climate is an essential factor in keeping the driver concentrated and offering comfort to all passengers.

Even in an aging society we want to support and contribute to the mobility wishes of all drivers. Denso is continuously developing concepts and new ideas which will create solutions for future increasing demands in the health and safety domain.

How is demand for multi-zoned air conditioning shaping up in Europe?

In the upper and premium vehicle segments you can recognise that OEMs are offering multi-zone systems. This trend is about to expand to lower vehicle segments such as B/C as well. Together with our customers, we at Denso have already developed these systems which will allow each passenger in a vehicle to adjust the car interior climate to her/his desired needs. This helps to create true additional value for the user.

In what ways have the regulatory forces driven recent innovation from Denso?

Our primary philosophy is to contribute to a better world, so we develop technologies which are environmentally friendly and efficient, thus reducing the fuel consumption of vehicles. Denso is developing highly efficient components, such as heat exchangers, compressors and low energy consumption HVAC units, in order to contribute to the global environment.

In addition, we are trying to reduce weight and size for all components as to continuously fulfil our customers’ needs.

And we want to contribute to safety and comfort too. For example, automatically controlled air conditioning systems will contribute to keep the driver concentrated on driving.

Lastly, we engage ourselves in the complete refrigerant cycle development and continuously support our customers as a system partner.

Not so long ago, air conditioning systems were noisy. How have you addressed this issue?

First of all, at Denso we use from a very early development phase very effective simulation tools to optimise the airflow in air conditioning systems. This allows us to achieve the necessary temperature control while reducing turbulence for less noise.

Secondly, we have developed new blower wheels and scrolls which reduce the overall noise level remarkably. The added benefit was the opportunity to reduce the blower size and in some operation modes the blower speed, which further reduces the noise.

Today we are facing requests to develop low noise HVAC units to cope with vehicle trends such as start-stop, hybrid vehicles, or electric vehicles. In addition, the demands for package reduction are getting more challenging. Therefore, the Denso experts are intensely analysing the frequency patterns which produce really disturbing noises, and then taking the necessary and appropriate measures.

How is Denso reducing HVAC related power consumption?

As previously mentioned, it is our passion at Denso to increase efficiency and reduce power consumption. The HVAC unit is just a part of a total system; therefore we not only are supplying low electric power consumption HVAC units (with highly efficient blower motors etc.) but also are supporting our customers with our system tuning know-how. In this sense thermal management means to reduce all energy losses. With our cold storage evaporator for example, we try to prevent early engine re-start during stops at traffic lights. And the Denso Ejector System which is installed in the HVAC unit can increase efficiency of the refrigerant cycle dramatically.

With the increasing interest in electric and hybrid vehicles from the auto manufacturers what developments are taking place for HVAC systems in such vehicles and what is Denso doing in this area?

Noise reduction and high-efficient heat generation are key issues in electric and hybrid vehicles because of engine-stop or engine-less operation.

The cabin cooling/warming systems are critical items because they consume a considerable amount of electric energy, reducing the vehicle driving range, especially in the winter period.

Denso is pioneer in developing air conditioning systems, optimised for hybrid and full electric applications. Some of these systems are already successfully in production, such as heat pump systems.

Our challenge is to continue to achieve the most efficient component optimisation and to cooperate with our customers in order to obtain the best vehicle integration, leading to the complete thermal management of electric and hybrid vehicles.

To what extent does a vehicle with stop-start impact on the effectiveness of the thermal management system?

Start-stop has been introduced to prevent vehicles from wasting fuel during traffic stops. During this engine stop time we at Denso try to keep the car interior at a comfortable temperature for the passenger(s) for as long as possible. Therefore we have developed a cold storage evaporator which stores cold energy and releases it when engine is stopped. In normal cases, no one in the car will feel any discomfort during this stopped period.