 John Lewis partners with EnerSys to improve efficiency for its warehouse fleet in Magna Park. |
UK retailer John Lewis Partnership has introduced a combination of PowerNet battery and power management systems from EnerSys Motive Power for its warehouse truck fleet at its newest distribution centre.
"We're getting better utilisation, better discipline, and better use of batteries," says Ted Weager, John Lewis' operations manager, MHE. "This installation has fulfilled our expectations."
The installation manages battery allocation at John Lewis' Magna Park, Milton Keynes centre to ensure balanced use, minimises energy consumption and prevents battery systems from drawing too much power when overall demand in the warehouse is above pre-determined limits. This ensures other services are not disrupted and avoids the need for costly, additional electrical infrastructure to keep the installation within budget.
The Magna Park distribution centre opened in 2009 and is John Lewis' latest investment to support sustained growth. The site covers around 800,000 sqft. (74,300 sqm), with separate zones allocated to different operations which serve the partnership's 30 retail stores and 20 distribution centres in the UK.
Jungheinrich was selected as the forklift supplier after a competitive tender and recommended EnerSys Motive Power for the battery systems. The fleet comprises very narrow aisle combination pallet stacker/order pickers, reach trucks, ride-on pallet transporters, pedestrian-powered pallet trucks, and electric counterbalance trucks.
Using detailed projections of the handling operations, the parties worked together to assess the battery management requirement. One of the key considerations was the provision of change and charge facilities for the warehouse trucks.
"We wanted a system that avoided the need for 100% spare batteries and offered balanced use to prolong their operational lifespan," Weager says. "We also wanted to make the best use of the power."
The warehouse works hard over extended shifts and the batteries need to support long intervals of up to eight hours between charging. The project team specified the highest-capacity batteries available for the various trucks to meet this objective.
EnerSys recommended a novel implementation of its PowerNet battery and power management system to oversee all charging and changing operations. A typical PowerNet installation allows operators to manage their charging patterns to take advantage of off-peak rates for lower price electricity. However, as the system runs on a standard personal computer and is completely configurable in software, it can be set up with a wide range of user-defined parameters to provide a unique set of performance characteristics.
"We decided to manage our power requirements with PowerNet rather than with a costly upgrade to the infrastructure," Weager says.
EnerSys UK sales manager Mike Gosling explains that the unique aspect of the installation is the way PowerNet is used to manage the consumption. "It also provides ideal rotation of batteries."
The batteries are charged with EnerSys Powertech HF chargers. According to EnerSys, these offer outstanding energy efficiency, up to 20 % higher than 50Hz chargers. They automatically detect the battery's level of discharge and will supply only the amount of power needed to restore full charge.
"The HF chargers are smaller and have a premium price, but they save on electricity which helps us meet our sustainability goals," Weager says.