Structural optimization of heat distribution networks
Heat distribution networks are used to transport, at the scale of a city or district, the heat, generated by one or more main sources, to the buildings where it is consumed, through a network containing a heat transfer fluid. The design of the network is considered here based on an algorithmic approach implementing digital optimization techniques. Formulation of the problem requires defining:
- Optimization variables: network topology, nature of the primary and secondary units, sizing parameters of the production/storage units and the network (storage capacities, length of the network branches, etc.), operating parameters of the storage/production units (primary energy consumption, etc.), system state variables (heat transfer fluid temperatures and flows at different points in the network, etc.).
- The objective function to be minimized/maximized: the total annualized cost of the network for example.
- The constraints that must be taken into account: operating constraints (building loads, etc.), model equations (energy and material balances, etc.).
It is a mixed integer nonlinear programming (MINLP) optimization problem.