Best practice case study

What counts

Smart power meters enable intelligent energy monitoring in chain stores

As a textile retailer, NKD always has its eye on the latest trends. But it’s staying ahead of the curve with its power meters – over the last few months, it has been replacing 1,300 analog meters with smart devices that use a communication interface. The devices were fitted by a competitive company which will also operate them on NKD’s behalf. This will benefit the retailer even before the official rollout in Germany.

In many European countries, it’s time for the winter sales. Retailers are hoping for cold winter weather and high turnover – but their power meters are working overtime. More than half of a store’s total electricity usage is generally accounted for by lighting, followed by air conditioning and ventilation. But cash registers, elevators, escalators and automatic doors are constantly consuming power, too.

To gain a clearer picture of its electricity demand, the textile retailer NKD has decided to replace the outdated analog power meters in its stores with smart meters – 1,300 of them. NKD commissioned the Aachen-based smart metering specialists Discovergy to replace its meters and operate the new ones in the summer of 2017. “We chose Discovergy as our service provider because they gave the best presentation and provided straightforward answers to our technical questions. They also offered the lowest price,” explains Alexander Pasquazi, head of the rental negotiations department at NKD.

NKD hat seine Filialen mit smarten Stromzählern ausgestattet.

NKD wanted to have a single point of contact for every aspect of meter operation – a way to streamline processes and cut costs. (Image: NKD)

Two payment models for consumers of all sizes

Discovery will finish replacing all of the company’s meters across Germany by early 2019. The meter operator has a large network of certified installers, without which it would be impossible to roll out smart meters on such a large scale. The old power meters are being replaced by smart devices which use either SLP or RLM metering. SLP stands for Standard Load Profile. This typical power meter model replaces the old black analog meters, including in private homes. It takes readings at two-second intervals to deliver energy statistics with excellent temporal resolution.

Several dozen larger NKD stores with high power consumption are to receive RLM metering devices. RLM stands for registered load measurement. These devices measure the load profile as the basis for an intelligent energy management system in companies with extremely high power consumption. If their electricity demand exceeds 100,000 kWh per year, companies are obliged by German law to use RLM metering. Discovergy’s RLM meters take power usage readings every 60 seconds. These highly precise figures make it possible to monitor consumption closely. The optical D0 interface means that the meters can also be easily integrated into a company’s in-house energy monitoring system.

Smart means more than just digital

Discovergy has fitted its meters with its proprietary communication module Gateway Meteroit 3.5, which is what turns digital meters into smart meters. The module combines WAN communication via LAN and GSM in a single piece of hardware. The smart meter transmits its readings to Discovergy’s servers for analysis in the company’s portal. This makes it easy for the energy managers at NKD to monitor power consumption in every store using Discovergy’s web portal and mobile app. Useful tools and a range of different options for visualization help create a clear picture of all relevant information. For example, visualizing power consumption can help to detect anomalies caused by faulty devices at an early stage. And a smart alert system will send a message immediately if any unusual patterns appear in consumption or generation. It’s also possible to compare figures for stores of the same size to encourage internal competition.

Cutting costs and saving labor

By fitting and operating NKD’s new meters, Discovergy is helping the textile retailer not only to improve energy efficiency but also to simplify logistic processes and cut costs Discovergy has a Germany-wide presence, meaning that NKD only needed to sign a single contract to bring the operator on board as its point of contact for all of its power meters. This saves an enormous amount of administrative work. In addition, having Discovergy operate the meters will cost less than relying on the individual meter operators who would otherwise be legally responsible for each site.

NKD’s new meters have been approved to remain in use for eight years, despite the rollout of intelligent measuring systems using smart meter gateways which should begin next year. The German Federal Office for Information Security (BSI) expects that at least three smart meter gateways will have completed the certification process by then, allowing it to classify intelligent measuring systems as being available on the market. Annual price caps will then apply to the installation and operation of this new measuring equipment. But NKD has no need to worry about the costs of this process either. “The price caps that will apply are almost twice as high as for our intelligent power meters,” says Discovergy sales manager Joachim Lang.

While the winter sales are good for business, Alexander Pasquazi hopes that this improved transparency will create potential for significant savings in the areas where consumption is highest, such as lighting, ventilation and other building technology. “All in all, we’re expecting to reduce our power consumption, our costs and our impact on the environment.”

By Simone Pabst

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Discovergy’s smart SLP meters are available as consumption meters, bi-directional meters, dual-tariff-rate hour meters, and supply meters without a backstop. (Images: Discovergy)

Lastgangzähler für registrierende Leistungsmessung bei Großverbrauchern.

The RLM meter takes power usage readings every 60 seconds. These highly precise figures make it possible to monitor consumption closely.