News
October 26, 2009 |
EC in supermarkets: Measurable savings
Eating is a sensory pleasure — but unfortunately buying food is often not. Karsten and Marcus Nüsken prove that this can be different in their seven Rewe supermarkets in Westphalia. The brothers explain how they managed to use EC technology to catapult one of their supermarkets into the top ten supermarkets in Europe.
Mr Nüsken, last year you fully refurbished one of your supermarkets and equipped it with new refrigeration units. How did EC motors come to be considered?
Marcus Nüsken: Our supplier for refrigeration units informed us of the savings potentials promised by the new ebm-papst fans. This convinced us that it is more worthwhile to accept higher procurement costs in the long term, because energy costs impact directly on my balance sheet. We converted all cooling units in the new supermarket to EC technology in one go, and the savings success was immediately measurable: despite a larger refrigeration configuration the consumption has fallen considerably. This impressed us. We have gone over to EC fans in three further supermarkets, and when I compare the overall power consumption it is apparent that these supermarkets have a far more efficient energy consumption.
Did you have ideal examples for your energy-saving measures?
Karsten Nüsken: No. Merely the trend in energy prices worried us. We thought about what we could do to keep the energy costs low in the long term. At first we had very practical ideas that showed great effect.
For instance?
Marcus Nüsken: Our heated cashier stations in the entrance area: it is often really uncomfortable at the doors. Above all in the period as the weather turns cold and the heating is not yet switched on. Therefore, instead of routing the waste heat from our cooling units out over the roof, we directed it into a water tank and transported it to the cashier stations. After all, we are speaking here of energy to the extent of 5,000 to 7,000 kW. Our cashier team no longer freeze and are very rarely ill.
Where do you see further saving potentials for electricity?
Marcus Nüsken: The awareness for energy efficiency will continue to rise; I therefore believe that EC motors will become the standard. But heat recovery from refrigeration machines is also an important topic. Many produce hot water as they operate, that is a nice approach, but it is not enough at all. I believe that we will see hardly any refrigerated shelves in the long term. It is important to keep the cold inside the units.
