Heller AG, located in St-Margrethen (Switzerland), has 10 employees and specialises in energy management systems for heat pumps, commercial and industrial cooling installations and refrigerated transport.
The company currently has refrigerated trucks including the Electro Truck which it hires to customers such as Frisco-Findus, Migros, Stadler Rail, and South-East railways.
Designed by Renault, the Electro Truck has an all-up weight of 13 tonnes and operates entirely by electricity.
Its large batteries are accommodated within the chassis. Given this new setup, Heller revised the design of the refrigeration system it normally uses in order to reduce its size to fit into this new truck.
A reduced-size Heller Eutekt 4 ESE unit with a 14 kg load of Performax® LT (R-407F) and fitted with a Copeland Scroll ZF13 KV E-TFD-551 compressor with enhanced vapour injection (EVI) was designed and installed. This compressor was chosen as it improves the COP by up to 27% according to standard EN12900 and has reduced electrical consumption relative to standard compressors.
The energy required to maintain cooling is stored electrically in the batteries overnight. The accumulated cooling power is sufficient for a full day of deliveries of daily orders to small
supermarkets, restaurants, etc. at the rate of 5 customers per hour with the doors being opened for a period of about three minutes each.
The installer chose R-407F refrigerant distributed by Climalife for the ElectroTruck given its GWP and energy efficiency.
Before being used in this new system, Heller had previously carried out a comparison with R-404A on a trailer and a refrigerated lorry when this fluid was launched.
After what was a conclusive experiment, R-407F with low GWP was deemed essential for this electric lorry and has enabled Heller to take a big step forward in its environmental and refrigerated transport modernisation programme in Switzerland.
This project has demonstrated how good a replacement R-407F is for the R-404A refrigerant used previously. Currently, 2 Electro Trucks are operating perfectly with Performax® LT, one around Zurich and the other around Lausanne. No problems have been reported.