Power consumption of electrical devices is often higher than specified

In reality, the power consumption of electrical devices is often up to 30 percent higher than indicated on the efficiency scales. In some cases, the consumption is even twice as high.

Berlin, Germany). The European Union's Energy Consumption Labeling Ordinance (EnVKV) is designed to make the energy consumption of electrical devices with colored efficiency scales visible at first glance, making it easier for customers to select energy-efficient products more easily. The regulation, which was last updated in July 2017, is intended to lead to stronger competition between manufacturers, which ultimately leads to lower electricity consumption due to energy-efficient devices.

According to the Closing the Reality Gap (PDF) study, which was carried out by the environmental protection organizations CLASP, ECOS, EEB and Topten.eu, the efficiency scale given on the label often does not correspond to realistic consumption in practice. Both normal household appliances and professional electrical appliances for trade and industry such as refrigerators and freezers often have a significantly higher power consumption in reality.

Inadequate test procedures result in incorrect energy consumption information

According to scientists from the European Environmental Bureau (EBB), this is because the method used in the test scenario does not match the application in reality. For this reason, the study authors identified four critical problem areas that need to be revised in order to be able to provide realistic energy consumption figures.

Unrealistic test methods: The usage scenarios that are used to determine the electricity consumption shown on the efficiency scales are unrealistic and allow manufacturers to advertise with energy consumption that in reality cannot be achieved by most users. This is why there are significant deviations, particularly in commercial refrigerators.

Outdated energy consumption requirements: The test standards are updated too rarely and therefore often take into account technical developments too late. For this reason, manufacturers can still achieve very good results in the tests even with actually outdated devices. A more regular update, on the other hand, would force companies to innovate and reduce electricity consumption.

Manipulation of the results: The criteria are not completely understandable and can be interpreted individually by different examiners. Different classifications of energy consumption can occur for the same electrical device. The ambiguous reproducibility of the results clearly contradicts scientific standards.

Confusing consumer information: Poor, missing and hardly understandable consumer information make it difficult for laypersons to estimate the electricity consumption and to make a purchase decision. In modern devices, this is made even more difficult by the large number of individual operating modes, because the efficiency scales cannot be used to read off their respective power consumption.

30 percent higher power consumption

For this reason, the scientists at the EBB have developed new, realistic test methods and tested them with different electrical devices. Among other things, the new methods provide that Ultra HD televisions are actually tested with Ultra HD videos, that the doors are opened regularly in refrigerators, and that the automatic program that is often used in practice is used in dishwashers. These test steps, which are essential for a realistic measurement of energy consumption, are not provided for in the EU test guidelines.

Depending on the electrical device, it turned out that the realistic electricity consumption is 20 to 30 percent higher than the consumption for which the efficiency scale was awarded. In some extreme cases, power consumption even doubled.

Parallels to the VW exhaust scandal?

Studies by American scientists also came to similar results, according to which in front of all televisions everyday electricity consumption is significantly higher than in laboratory tests. The results also point to parallels to the VW exhaust scandal. According to the US studies, it is likely that electrical devices will also reduce their own electricity consumption if they notice that a test procedure is in progress. A reduction in backlighting that is not immediately visible to the naked eye is sufficient for this.

Sources of article:
https://www.forschung-und-wissen.de/nachrichten/technik/stromverbrauch-von-elektrogeraeten-oft-hoeher-als-angegeben-13373701