Starting this week, transmission system operators in Germany, the Netherlands, Switzerland and Austria are conducting a common tender for primary control power for the first time. With a total tendered output of 783 megawatts, this will create the largest single market for primary control reserve power in Europe. The common tender enables the most cost-efficient power stations to provide primary control power across national borders. The transmission system operators are expecting reduced procurement costs for primary control power thanks to this extended tender. In Germany, this price decrease will be passed on to the grid customers in its entirety. The total cost of primary control power in Germany amounted to approximately 100 million euros in 2014.
The European transmission system operators are procuring control power in order to ensure the balance between generation and consumption on the European grid at all times. The fastest type of control power, which is required for regulating very short-term balance deviations, is the so-called primary control power. Each transmission system operator in Europe is responsible for providing a certain share of the total primary control power required. The transmission system operators are allowed to procure the control power from outside their own control area if they can ensure that acquisition of the control power will not result in a power grid overload. Thus far, two such cooperative endeavours have taken place: one between Germany, the Netherlands and Switzerland; the other between Austria and Switzerland. These have now been combined – for the first time, it is possible to conduct a common tender for primary control power involving all the countries mentioned above while taking grid restrictions into account.
About primary control power
Electrical energy cannot be stored in large quantities. This is why it is crucial that the quantity of electrical energy generated is always exactly the same as the quantity that is consumed. This balance ensures the safe operation of the grid at a constant frequency of 50 Hertz. Unexpected fluctuations between the grid inflow and grid outflow of electrical energy must be balanced on a short-term basis. In order to be able to balance such fluctuations within seconds, the so-called primary control power is used. Power stations that are suited for primary control power can increase or decrease their power output within few seconds. The transmission system operators procure the required primary control power through weekly market tenders. Only providers that have previously passed a technical and organisational examination (a so-called pre-qualification process) are allowed to participate in these tenders.
