In an increasingly competitive marketplace the electricity bill is one of the largest costs in a supermarket. As energy prices soar, an increasing number of retailers are looking for cost-efficient ways to reduce their energy consumption and strengthen their bottom lines. At the same time there is more interest than ever in ensuring a healthy business that also protects the environment.
This is partly why heating, ventilation, air-conditioning and lighting systems, which consume significant amounts of energy, are obvious candidates for energy saving activities in the worldwide retail industry.
No cure, no pay
In 2006 Danfoss won a contract with the Praktiker Group to review the chain's energy consumption. The deal was that if the DIY company did not achieve the promised savings, Danfoss' services were free. Danfoss' experts started by taking a closer look at the energy bill in the store in question.
Viktor Klose Manager, Field Service Manger at Danfoss, worked closely with the customer in all phases of the project from planning and commissioning to implementation. The first task in any project is to gather information about the current state of a store's energy consumption.
"If we don't have sufficient details about the shop's energy consumption, we start looking at the energy bills through the last 2-3 years. Then we calculate the energy consumption per square meter per year. If the results show improvement potential, we start looking closer", he says.
The next step is to gain a more detailed view of the energy consumption. By installing power meters it is possible to see where energy is being wasted. This provides the best starting point for initiating actual improvement activities, which usually are built up around a building management system that makes it easy to get an overview and fine tune how the many different systems use their energy.
"At this point we usually install a system manager, which can control most of a shop's systems, including refrigeration, HVAC and lighting via bus system. After a period where we optimise overall system performance, the shop's new energy management set up is ready to start on the big savings", says Mr Klose.
Three year return on investment
Since 2006 Praktiker has installed Danfoss energy management systems at 24 German Praktiker stores. So far the chain has saved 6,9 million kWh of energy, which has reduced the chain's CO2 emissions by 4250 tons, in addition to the money that now lands on Praktiker's bottom line. "When we say 'no cure - no pay', we mean it. Not only do we guarantee significant savings, we also promise a payback time of no more than three years on the customer's investment. So far we have never failed to keep our promises. In fact, some of the stores achieved payback in only two years," concludes Rainer Mähringer, Business Development Manager and building management expert at Danfoss.
Illustration to the right:
Energy consumption table at Praktiker, Bonn
By optimising Praktiker's Bonn branch the store reduced its annual energy consumption by more than 28% between 2006 and 2009, resulting in a reduction in the company's CO2 emissions by 220 tons.
Increasing interest in energy savings
In recent years typical HVAC systems have become increasingly efficient, as new energy management systems have replaced old and outdated technologies.
"We talk to many customers who want better control of their energy consumption. Danfoss already offers a wide range of proven technologies for refrigeration control, but now customers are really interested in adding heating and lighting to their control systems and controlling it all via a single interface," says Business Development Manager and building management expert at Danfoss, Rainer Mähringer, who says that most customers have a hidden potential for reducing their costs.
"In our experience, many customers are unaware of the effect their lighting has on their energy bill. Sometimes lights are left on during the day, when they could have been turned off. Other times all indoor and outdoor lights burn all night, even though the shop is closed. Although time controlled switches can to a certain extent make a difference, they cannot match the advantages of an intelligent system that continuously adapts to changing conditions", says Rainer Mähringer.