Power grids

Electricity is more than just electricity! - The quality is crucial

When talking about supplying quality electrical energy, the word quality might refer to the continuity of supply, voltage quality or commercial quality.

Comparisons on the continuity of supply, voltage quality and commercial quality between the countries in the European Union are published by the Council of European Energy Regulators (CEER) in the 6th Benchmarking Report on the Quality of Electricity Supply.


Continuity of supply

Continuity of supply is measured by the average frequency and duration of interruptions to customer service. The rating provides a set of reliability metrics, so-called failure indices. At the moment there is an effort at European level to standardise these indices in a new European standard. The aim is to enable a comparison of the supply landscape across Europe because continuity of supply is an essential factor for many branches of industry when choosing a location.

Voltage quality

The voltage quality describes the technical characteristics of the supplied voltage. It is a measure of the usability of the supplied electrical energy and thus essential for the functioning of devices at the customer level. The essential parameters of the voltage quality are defined in the European standard EN 50160 and describe the deviation of the voltage from its ideal sinusoidal shape. Computers, televisions, home appliances but also in particular industrial measurement and control devices only work properly if the voltage quality is suitable.

The members of Oesterreichs Energie have been raising the quality of voltage for years using standardised methods. Every year, two measurement campaigns are carried out during which the voltage quality is measured at certain points in the domestic electricity grid within a specified week period. The results are published regularly in Oesterreichs Energie trade journal.

Commercial quality

Commercial quality is currently not yet fully defined. It includes the services provided by the distribution system operator to its customer. Indicators could be requirements for defined services, such as the grid connection, the availability and the response time of the telephone service. The 6th CEER Benchmarking Report also deals with commercial quality, but a European comparison is only of limited significance due to a lack of comparable indices.

Grid quality

Grid quality is a good indicator of the actual condition of the grids. It should therefore be emphasised again at this point how important it is, especially in the liberalised market, for the grid operator to fully acknowledge the costs of maintaining and expanding grids. As this is the only way for them to permanently maintain the usual grid quality in the future.