Intelligent defrosting systems to increase energy efficiency

Ice, frost or frost build-up on heat exchangers is a persistent problem in the freezer and normal refrigeration sectors. Continuous icing consistently throws a wrench in operators' plans, as iced cold rooms are more inefficient. Ice buildup has two detrimental effects: First, it acts as an insulating layer between the heat exchanger and the airflow, and second, it blocks the flow path between the fins. Both effects lead to a significantly poorer thermodynamic efficiency of the system, which has to be compensated by increased power consumption. To avoid and combat this undesirable ice build-up, there are different defrosting methods to choose from, such as hot gas, or electric defrosting. But, basically, the defrosts in each system are pre-programmed either at specific times or over fixed time intervals. If a plant is equipped with an electronic system that can skip some defrosting times, it is called "demand defrosting". These conventional defrosting controls do not take into account the actual icing condition of the plant or the demanding logistical operations of a plant.

This is because the operating conditions in the cold stores change in the short and long term. Irregular goods handling, moisture ingress, weather changes and icing due to open storage doors are some examples. All of these conditions have a significant impact on ice formation at the heat exchanger and must be considered if cold rooms are to operate under optimal conditions. A key technology to control defrosting more accurately and intelligently lies in direct measurement of ice formation at the heat exchanger. Coldsense Technologies GmbH has combined a system solution with precise eidetectors to reliably detect the actual ice formation on the heat exchangers. This allows the start but also the length of each defrost cycle to be precisely controlled. However, the innovation and further energy savings with this system are based not only on measuring ice formation in real time, but also on monitoring and controlling the cold rooms with advanced artificial intelligence algorithms. With monitoring, the system detects irregular arrival of goods, humidity entry, door movements, etc. This allows the equipment to be optimized and the necessary defrosting to be initiated automatically and as required.

(machine translated)