Entry- & exitcapacity
We use the entry-exit system for selling gas transmission services. This means that the pipeline network has entry points (about 50) and exit points (about 1,100). An entry point is a place in the pipeline network where the gas can be physically injected into the system, an exit point is a place where the gas can be physically removed from the system (for example, a gas delivery station or an export station).
Our customers buy capacity in advance at these entry and exit points so that they can inject gas into the system at a specific point and take it off again at a different location (= transport). The customer is free to choose the combinations of entry and exit points but must ensure that a certain balance is maintained between the volume of gas injected into the system and the volume taken off. That is why we have set up a balancing regime.
We provide both firm (assured) and interruptible entry and exit capacity. Firm capacity means that the customer is sure that he can use the capacity he has purchased. That is not the case with interruptible capacity, where there is a certain chance of interruption. Interruptible capacity will only be sold when all firm capacity is sold out. Capacity with a higher probability of being interrupted will only be sold when all capacity with a lower probability of being interrupted is sold out.
The gas present in our system can change ownership easily before it leaves the system at an exit point. This makes gas trading possible (see also the gas trading exchange, the TTF).