Special types of grid use
50hertz is obliged to offer individual transmission charges to grid users with special take-off patterns as specified in detail in the German Ordinance on Power System Charges (StromNEV).
An individual use-of-system charge must be offered in the following cases:
- The customer’s effective demand will predictably deviate considerably from the synchronous annual maximum demand of all take-off from this system or transformation level (atypical grid use);
- Electricity taken from the general supply system for the customer’s own use at the take-off point reached a minimum utilisation of 7,500 hours in the last calendar year, and electricity consumption at this take-off point at the same time exceeded 10 gigawatt-hours in the last calendar year (intensive grid use).
The resulting individual use-of-system charge must reflect this customer’s contribution to the reduction or prevention of increases in grid costs at this grid level, and must not fall below 20% of the disclosed use-of-system charge.
In favour of atypical grid users, the system operator has to determine high-load time windows on the basis of the take-off load profiles observed in the preceding year.
The regulator Bundesnetzagentur must approve any such individually agreed charge. A relevant application may as well be submitted by the customer. Should it turn out that the customer fails to meet the above-mentioned conditions for such a special take-off pattern, billing shall be based on the valid current price list.
At the end of 2010, individual use-of-system charges had been agreed by 50Hertz with the following customers:
- Pumped-storage power plants of Vattenfall Europe Generation
- Brandenburg and Hennigsdorf electric steel plants
- Trimet Aluminium in Hamburg