Co-operative Food Retail Logistics brought in EnerSys to redesign its MHE battery charging area and install a battery management system, at its Birtley distribution centre in County Durham.
As a result it has streamlined operations, freed up warehouse space, reduced forklift downtime, and cut manual handling.
The 285,000 sq ft hub opened in April 2009 and incorporates ambient, chilled and frozen storage. From here goods are distributed to 260 Co-operative stores throughout the North East and Scottish borders.
Voice picking technology is a feature of the site, in which the 500 staff must fulfil more than 200 deliveries a day; picking half a million cases a week. And a 61-strong fleet of Linde forklift trucks, including pallet transporters, low level order pickers and reach trucks, operate at the site.
The company wanted to cut all manual handling of batteries and bring in the latest battery management technology. It currently has some 2,000 of EnerSys’ Hawker Evolution gelled electrolyte batteries across its 19 sites. These require no topping up and there is no risk of spillage. A valve-regulated re-combination technology reduces gas emissions, making them well suited to food distribution operations.
Chas Shepperson, national MHE fleet manager at Co-operative Food Retail Logistics, says: “The gelled electrolyte means there is no spillage so they are safer and there are no problems with corrosion. Reduced gassing means we don’t need special ventilation. The training required is also much simpler.”
EnerSys built a three-tier battery bank, which is served by an electric-powered changing cart, believed to be the first of its type in the EU to work without hydraulics. It also developed a new version of the Hawker Pro Series BBH bull handling equipment, featuring hydraulics that could cope with an additional fourth tier, if it were ever needed.
The system comprises two identical banks, each with space for 42 batteries, arranged back-to-back with their own BBH. This means one of the systems can be taken off-line for maintenance while the other continues to supply charged batteries.
The central aisle which runs between the two banks allows for engineers to check, monitor and maintain the chargers without entering truck operating areas. “With this arrangement we can keep the site operating at all times,” says Shepperson.
The Pro-Series BBH is a semi-automated electric-powered change cart that runs on concealed rails alongside the row of chargers. When a change is required, the truck approaches the changing area and the driver disconnects its battery.
An extending electro-magnet on the BBH extracts the battery from the truck onto its on-board roller bed and then pushes it into place for charging. The device can be raised to handle batteries on the second and third levels in the charging banks.
The company says the BBH is simple to operate. “We generally expect to change a battery in around 90 seconds,” says Shepperson.
The Co-operative uses EnerSys’ Powertech HF chargers, which it reckons are 20 per cent more energy efficient than 50Hz chargers.
The chargers automatically detect the battery’s level of discharge and will supply only the amount of power needed to restore full charge. This means less mains power is required to charge a battery and the energy costs per charge are reduced. EnerSys says that with the Evolution battery electricity savings can be some 30 per cent.
EnerSys’ Battery Management System oversees all operations. The diagnostic software in the chargers transmits data via the system’s PC to a large display screen installed in the battery changing area. The display indicates the order in which batteries for each type of truck should be retrieved, ensuring that only fully-charged units are taken.
This ensures all batteries receive the correct amount of charge before being used, and that they are systematically rotated; meaning operators can’t take the nearest available battery, regardless of its state of charge. The system also ensures that batteries are charged during lower tariff overnight periods, which helps reduce costs further.
Previously, the company would allocate two spare batteries for each truck, but now only needs to source one. It says this has resulted in “considerable capital savings” for the group, and means less space is needed for battery storage.
The management system operates in conjunction with the remote monitoring and diagnostic Powernet service from Enersys. At any time managers from EnerSys can connect to the system from their own sites and download a wide range of battery-related information.