Optimal Operations Management and Network Planning of a District Heating System with a Combined Heat and Power Plant

District heating plants are becoming more common in European cities, especially in the northern countries. These systems make it possible to furnish users with warm water while locating the production plants in the outskirts. This has the double benefit of lowering the impact of pollution on the center of the city and achieving better conversion performances compared to individual heating plants. Moreover, this kind of plant can exploit alternative energy sources, such as the burning of urban waste or biomass, or geothermal sources. In order to amortize the costs throughout the year, the system often includes a combined heat and power (CHP) plant, in order to exploit the energy during the summer as well, when the demand for warm water decreases. A linear programming model for the optimal resource management of such a plant is presented and some results for a real case are reported. The problem of planning the distribution network is also addressed. This problem has a nonlinear nature but can be linearized and solved by means of Mixed Integer Linear Programming packages.