Invited Session Thu.1.MA 549

Thursday, 10:30 - 12:00 h, Room: MA 549

Cluster 18: Optimization in energy systems [...]

Capacity of gas transport networks


Chair: Thorsten Koch



Thursday, 10:30 - 10:55 h, Room: MA 549, Talk 1

Christine Hayn
Optimal allocation of capacities in gas networks

Coauthor: Lars Schewe


Due to regulations gas network operators face the new challenge of allocating free capacity at all entry and exit points.
Customers may then book within the reported capacity intervals separately at the entry and exit points.
Operators have to guarantee that all expected requests within these intervals (called nominations) can be transported through the network.
Where no historical withdrawal data is applicable, the worst-case request situation has to be considered.
However, due to gas physics and active elements like compressors, the underlying question whether a nomination can be transported through the network, called nomination validation, already is far from being trivial and is modelled as a non-convex MINLP.
Thus, it is not obvious what the operating limits of the network are.
We discuss the hardness of the capacity allocation problem and propose an algorithm for solving a relaxed variant. Therein a nomination validation tool is used as black box.
The potential of our implementation is demonstrated on real-life instances from gas network optimization.



Thursday, 11:00 - 11:25 h, Room: MA 549, Talk 2

Lars Schewe
Mixed-integer-programming methods for gas network optimization

Coauthors: Björn Geißler, Alexander Martin, Antonio Morsi


We present methods to formulate and solve MINLPs originating in stationary gas network optimization. To this aim we use a hierachy of
MIP-relaxations. With this hierarchy we are able to give tight
relaxations of the underlying MINLP. The methods we present can be
generalized to other non-linear network optimization problems with
binary decisions. We give computational results for a number of real
world instances. The underlying optimization problem can be adapted to
give operating limits for the network in fixed scenarios. These
results can be used as the basic building block for further study of
the allocation of capacities in the network.



Thursday, 11:30 - 11:55 h, Room: MA 549, Talk 3

Benjamin Hiller
An automated method for the booking validation problem

Coauthors: Hernan Leovey, Andris Möller, Werner Römisch


We propose an automated approach to solve the booking validation
problem faced by gas network operators: Given a set of transmission
capacity contracts (a booking), check whether all balanced gas flows
that may result from those contracts are technically realizable. Our
approach is based on MINLP methods for checking gas flow realizability
complemented by a method for generating a representative subset of the
gas flows that may arise. This generation method combines a stochastic
model for gas offtakes and a deterministic model for the contractual
limitations of both injections and offtakes.


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