Quehenberger Logistics GmbH’s logistics site in Enns is one of the most important hubs for the company, which operates throughout Europe. To guarantee constant availability of the electric forklift trucks for their internal material flow, the company relies on innovative battery charging technology from Fronius. The Selectiva battery charging systems and “Cool Battery Guide Easy” information and management system ensure optimum utilisation of the battery pool, as well as an ultra-gentle and energy-efficient charging process. These advantages mean Quehenberger not only benefits from a reliable, fully functioning stacker fleet, but also significantly lower operating costs.
Quehenberger Logistics GmbH’s transhipment warehouse in Enns, Upper Austria, handles all manner of items – from toothbrushes and gummy bears to t-shirts, car tyres and fridges. Lorries constantly dock at the warehouse’s 62 gates to deliver or collect goods. With a total storage area of 25,000 square metres, the site is one of the logistics company’s largest and most important nerve centres. The transhipment warehouse, which was commissioned in 2007 and occupies an area of 7,000 m², is an important part of the site. Thirty-six employees work around the clock on a three-shift system storing, retrieving and transferring goods.
Quehenberger Logistics is a medium-sized logistics company specialising in transport management, and network and contract logistics. As part of the Augustin Quehenberger Group, which has over 89 sites in 18 countries, the company has an extensive international network to draw on. Quehenberger’s principal operations are focused on central and eastern Europe, but it is also active in other areas like Scandinavia. The Enns site is mainly responsible for the transport logistics of several well-known food, chemist and textile retailers and supplies their branches throughout Austria and abroad. Its QX Express service supplies goods in particularly short turnaround times. White goods, such as washing machines, fridges and other electrical appliances, are transported to retailers or directly to customers’ homes (including installation) depending on requirements.
Forklift trucks in constant use
“We used to specialise in logistics for car tyres, but over the years our portfolio has expanded,” says Thomas Putschögl, head of technical operations at Quehenberger in Enns. “Today we handle the logistics for all sectors and have a broad customer base.” Around 1,200 items leave the transhipment warehouse every day, which certainly poses a challenge for the company’s intralogistics: 20 electrically powered Linde forklift trucks are constantly in operation between the storage areas and the individual lorries. As they need to be available at all times, Quehenberger also uses spare batteries that are kept at a central charging station.
“Our stackers rack up roughly 150 operating hours a week,” explains Putschögl. “This simply wouldn’t be possible without changing the batteries.” In the past, however, the company constantly ran into problems, as it was not immediately obvious to the employees how long the batteries had been connected to the chargers. The utilisation of the battery pool suffered as a result, as Putschögl recalls: “Often a driver would simply take the very first battery for ease, regardless of whether it was already fully charged and had cooled.” This not only reduced the availability of the forklift trucks, but also the service life of the costly traction batteries.
Combining energy efficiency and availability
In 2015, Quehenberger decided to replace the entire stacker fleet at the Enns site with state-of-the-art technology. Battery charging technology also formed part of the management’s decision: “Our objective was to have a system that ensures the constant availability of our forklift trucks, while charging the batteries as gently, energy efficiently and cost effectively as possible,” outlines Putschögl. The firm soon came across Fronius, the company based in Pettenbach, Upper Austria, specialising in innovative battery charging systems that enable users to make considerable savings on operating costs.
“Quehenberger had previously commissioned us to calculate the potential savings to be made with battery charging technology,” recalls Leopold Grammerstätter, technical consultant for battery charging systems at Fronius. This was enough to convince them, since Selectiva chargers from Fronius use up to 30 percent less energy than conventional solutions due to the specially developed Ri charging process. Charging is also ultra gentle, which increases the service life of the batteries – another cost factor. Quehenberger therefore opted to equip its logistics site with a total of 42 Fronius devices.
Individual charging process protects the battery
The major advantage of the Ri charging process is that it does not follow a fixed characteristic, but instead adapts according to the age, temperature and state of charge of the individual battery, as Grammerstätter explains: “The effective inner resistance – also known as the Ri – depends on these factors, and this in turn influences the charging current.” Every charging cycle therefore has a unique characteristic adapted to the individual requirements of the battery. This minimises overcharging at the start of the charging process and during the recharging phase, which is responsible for high energy losses and warming of the battery. The result: “Power consumption and CO2 emissions are significantly lower and charging is gentler compared to other systems,” emphasises Grammerstätter. “Both of these factors have a positive effect on the total operating costs.”
But it doesn’t stop there; to guarantee maximum availability of the forklift truck fleet, Fronius also installed the “Cool Battery Guide Easy” information and management system. Its job is to intuitively guide the stacker driver to the battery that has been fully charged for the longest and is therefore the coolest. “An LED strip is attached to each charger. The device that completed the charging process first lights up blue, so that the driver knows at first glance, which battery should be used,” explains Alexander Grünhagen, warehouse manager at Quehenberger, highlighting the advantage of the new system. “This means all the batteries are in use with the same frequency and are always fully charged, extending their service lives. At the same time this increases the performance and availability of our stackers.”
High demands entirely satisfied
The technology from Fronius quickly revealed other benefits during daily operations, explains Grünhagen: “Gas emissions are considerably lower with the new devices, along with the offensive smell.” Thanks to the gentle charging process, the batteries also lose much less water, which has done away with the frequent and time-consuming job of topping them up. In addition, the Selectiva devices are flexible enough to charge different types of batteries. This makes it easier to change the batteries, as employees no longer have to waste time matching up the batteries with the right charger. Grünhagen and his colleagues are even proud of the new charging station, he says with a smile: “The visual impression and clean installation alone make everyone handle the devices with care.”
Manager Thomas Putschögl is also very satisfied with the Fronius solution: “We have no problems meeting the high availability demands of our fleet of forklift trucks,” he praises. “What’s more, the innovative charging technology has helped us make considerable savings when it comes to operating costs and CO2 emissions.” This is a clear advantage with respect to the new energy efficiency laws in Austria and Europe. “Thanks to Fronius our intralogistics are well equipped to meet the challenges of the future.”