Temperature under control: Temperature monitoring with IoT for greater transparency, safety and efficiency

Stable temperature conditions along the entire logistics chain are important to ensure that fresh food gets safely from the production site to the shelf. Nagel-Group has worked with the technology company Enerthing to develop an innovative temperature monitoring system with a view to raising this quality standard and at the same time making processes more efficient. The aim is to seamlessly document temperature curves, identify fluctuations at an early stage and systematically exploit potential energy savings.

“Enerthing is the perfect retrofit implementation partner for us,” says Jannis Pohl, IoT Project Manager at Nagel-Group. The foundation stone for the work with Enerthing was laid in 2022. Within just three months, the project partners had developed an initial solution, which was successfully implemented at the first location in June of the same year. The system consists of autonomous IoT sensors that record actual temperatures in the storage area and automatically raise an alert in the event of any deviations.

The project was not purely about increasing efficiency and fulfilling HACCP requirements; it was also triggered by strategic sustainability goals. The new solution supports the implementation of ESG criteria (environment, social, governance), particularly with regard to environmental responsibility and resource conservation. At the same time, reporting capability is significantly improved – an increasingly important aspect when it comes to regulatory requirements such as the Corporate Sustainability Reporting Directive (CSRD) and the EU Taxonomy Regulation.

The minimum requirements for the sensors were defined in close cooperation with the quality management team during the design phase, and site-specific requirements were taken into account. For example, the number of sensors to be placed in relation to the size of the hall in order to ensure complete monitoring of the ambient temperature was determined. The technology is now in use at 64 Nagel-Group locations in Germany – with a further 46 branches to follow by the end of 2026. “Our aim is to create a standardised Europe-wide solution to replace existing systems,” explains Andreas Kaup, Control Technician Real Estate at Nagel-Group.

Process reliability through intelligent temperature monitoring

The sensors work completely independently – no batteries or external power supply are needed. They draw their energy from the hall lighting and store it in an integrated rechargeable battery. This advantage means that the sensors can be integrated into existing infrastructures within a single day. The devices are also maintenance-free. “We always try to integrate our solutions seamlessly into existing processes: with the minimum of disruption and as quickly as possible,” says Dr Michael Niggemann, Managing Director of Enerthing.

The number of sensors has been increased from the previous solution, and placements optimised so that the new secondary temperature monitoring system measures the temperature closer to the goods – at different heights and in the immediate vicinity of the shelves. This provides more meaningful values that can be used to calculate an average room temperature. This is automatically transmitted to the cloud-based enerCloud platform and can be accessed anytime and anywhere. The system identifies at an early stage if the temperature varies from the desired level – and before critical limit values are exceeded. In this case, those responsible are automatically alerted by e-mail before the alarm chain is set in motion. The alarm plans can be customised to the respective location and time of day (e.g. working day, weekend, night operation) to ensure a rapid response and timely intervention.

Options for action can also be derived from the data. “This allows us to detect whether a hall is being cooled too much,” explains Jannis Pohl. “We can therefore make targeted adjustments to the temperatures and save energy.”

In addition to temperature deviations, the sensors also register strong jolts, which may indicate possible tampering or damage. An alarm is also triggered in such a case. The system is also ready for any network failure: the sensors can store temperature data locally for up to 72 hours and automatically transmit it the moment the connection is re-established. A notification is sent to those responsible one hour after the system fails, prompting a manual check to be made. The existing maintenance contract takes all downtime options into account, so that it is possible to react and take countermeasures at short notice within a time window of just 72 hours.

Sensor technology as the key to efficient energy management

Humidity as well as temperature is an important factor in certain cases, for example when storing and maturing cheese. The sensors provide valuable data on this too, and the function can be activated remotely if required. This means that each location can decide individually whether it wants to use this function.

The temperature data obtained can be used for energy management as well. For example, it provides information on how much cold reserve is available and whether this can be used for upcoming deliveries. This allows energy costs to be better planned and specifically reduced.

Forward-looking developments

“Enerthing always reacts flexibly and quickly to our wishes, which is why we will continue to develop our systems infrastructure together with them,” says Andreas Kaup. Work is currently underway on door sensors that will analyse possible energy losses when warehouse doors are opened and closed. The aim is to better understand the loss mechanisms that occur, evaluate them in monetary terms and derive targeted measures to increase efficiency. In future, the running times of the doors will also be recorded so that changes that indicate icing can be identified – this means that alerts can be triggered in the event of deviations in running times and de-icing measures can be initiated in good time.

“Once the infrastructure has been set up, new applications can be easily integrated,” explains Jannis Pohl. “We are currently analysing all the data collected in order to develop further use cases.” Initial tests around artificial intelligence, such as AI-controlled electricity purchasing, are also already underway.

This innovation in food logistics represents a further step for Nagel-Group towards sustainable and energy-efficient operations – and offering its customers greater transparency, safety and higher quality along the entire supply chain.