STILL electric forklifts equipped with high-power self-cooling batteries have replaced diesel forklifts at Lünewell’s modern corrugated paper plant in Germany.
The two companies involved
The medium-sized family business Lünewell produces more than 150 million square metres per year of corrugated board using cutting-edge technology in its new production hall in Lüneburg, Germany. Every day, trucks deliver around 72 rolls of paper to the facility. These huge rolls stand 2.5 metres high and weigh up to 3.8 tonnes each.
STILL is a leading supplier of forklift trucks, platform trucks and tractors plus the latest Intralogistics systems. The company has around 9,000 employees, four production plants, 17 subsidiary companies around the world, plus a dealer network consisting of 246 dealers worldwide.
Lünewell wanted to reduce its environmental footprint and improve the working conditions at its corrugated board production hall. The company therefore decided to replace its diesel forklift trucks with efficient, emission-free electric forklift trucks from STILL.
The case for electric
Although capable of handling heavy loads, diesel forklift truck engines often have to be fitted with additional components such as diesel catalytic converters, particle filters and Selective Catalytic Reduction (SCR) catalysts to reduce nitrogen oxide emissions (NOX) for indoor use. This is apart from their high CO2 emissions.
Lünewell purchased two STILL RX 60-80 electric forklift trucks to cope with the challenge of handling the huge, heavy rolls of paper. These powerful vehicles are able to unload the paper rolls from the trucks, carry them into the warehouse, and then stack them up in threes to a total height of 7.5 metres. The forklifts also feed the paper rolls into the production machine. The two forklifts run on average 1,200 operating hours per year.
In addition, Lünewell acquired four smaller electric forklifts from STILL for other paper handling tasks in the warehouse: three RX 60-35 units that operate at 2,000 hours per year, and one RX 60-50 unit that operates around 1,200 hours per year.
In heavy-duty electric forklift truck applications that consume a lot of power – such as the handling of heavy paper rolls – the core temperature of lead acid batteries can get too high. Until now, the only solution was to install additional (but expensive) special batteries with a high energy density.
STILL’s PowerPlusLife battery offers a cost-effective solution. Thanks to its patented self-cooling system, a number of temperature-controlled fans cool the battery’s core effectively in any situation.
Every STILL electric forklift in use at the Lünewell warehouse is fitted with a STILL air-cooled PowerPlusLife battery to ensure high handling capacity.
REDUCED CO2 EMISSIONS
The previous diesel-powered forklifts were consuming an average of 9.2 litres of diesel fuel per hour. A factor 2.64 kg CO2 of diesel = 24.28 kg CO2 emissions per hour.
The RX60-80 electric forklift has an energy mix of 0.537 kg CO2/KWh (source: UBA 2017), plus 50% for waste heat during charging and operation of battery = 0.805 kg CO2/hour. An average energy consumption of the forklift of 17.7 KWh/h = 14.25 kg CO2 emissions total per hour.
In other words, a CO2 emissions reduction of 41.3% was achieved.
The graph below shows the Total Cost of Ownership of diesel and electric forklift trucks based on Capex, energy and service costs.
TCO assessment shows that initial Capex investment costs for full-electric forklifts in this class, including battery pack and charger, are about 10% to 15% higher than diesel forklifts. However, the running Opex (including maintenance, repair and energy fuel costs for operations) are lower with the electric forklifts. In the example shown in the illustration of one-shift and 1,100 annual operating hours, the full-electric model reaches break-even after less than two years of operation and then shows TCO benefits of almost € 10,000 over five years of operation.
BETTER, HEALTHIER WORKING CONDITIONS
- Clean air: In contrast to diesel engines which need additional systems for emission after-treatment (e.g. DPF, SCR), electric forklifts are zero-emission vehicles which means a warehouse with cleaner, healthier air.
- Less noise: The electric forklifts have significantly reduced the noise pollution inside the warehouse, making it a more comfortable and enjoyable place to work.
STILL’s 8-tonne RX 60-80 electric forklift trucks have a load capacity comparable to powerful forklift trucks powered by combustion engines. Reduction of the forklift truck battery’s core temperature is the crucial factor. Thanks to STILL’s PowerPlusLife battery, cooling prevents a loss of capacity. The batteries therefore do not need to be changed as often. Together with the fast lateral battery change and the manoeuvrability of the RX 60-80, the bottom line is an increase in load capacity.
Text: Tomas Jezdinsky, Denzil Walton, Diedert Debusscher, European Copper Institute Technical Author: Gerd Knehr, Reutlingen, Germany download PDF