Determination of Optimal District Heating Pipe Network Configuration

Abstract: - In this article the developed mathematical model, which based on simplex method is presented. The mathematical model, consisting of the non – linear objective function and system of non – linear equations for the hydraulics limitations is developed. On its basis the computer program for determination optimal tree path with the use of simplex method was solved. For economic estimation the capitalized value method, which consider all costs of investment and operation was used. The simulation is done on a pipe network with 22 pipes and 13 nodes. Key-Words: - Heating; Pipe network; Optimisation; Nonlinear programming; Simplex method 1 Introduction Nowadays, great emphasises are on search the solutions for savings and rational energy use, due to rapid population growth, increasing environmental problems and reduce energy sources as a result of excessive consumption of natural sources in the past [1, 2, 3 ]. Climate changes are mainly the consequences of enormous greenhouse gas emissions, which arising from consumer lifestyles in industrialized countries. In the focus to decrease climate changes we have to start reducing greenhouse gas emissions where they arise. This requires the search for new engineering and scientific solutions in the field of thermal and process engineering. One of the potential for reducing environmental pollution and lower energy consumption is district heating systems represent in urban settlements. They enable primary energy savings and are acceptable from ecological point of view [4, 5]. District heating has various advantages compared to individual heating systems. Usually district heating is more energy efficient, due to simultaneous production of heat and electricity in combined heat and power generation plants. The larger combustion units also have a more advanced flue gas cleaning than single boiler systems. In the case of surplus heat from industries, district heating systems do not use additional fuel because they use heat which would be disbursed to the environment. District heating is a longterm commitment that fits poorly with a focus on short-term returns on investment. Benefits to the community include avoided costs of energy, through the use of surplus and wasted heat energy, and reduced investment in individual household or building heating equipment. District heating networks, heat-only boiler stations, and cogeneration plants require high initial capital expenditure and financing. Only if considered as longterm investments will these translate into profitable operations for the owners of district heating systems, or combined heat and power plant operators. District heating is less attractive for areas with low population densities, as the investment per household is considerably higher. Also it is less attractive in areas of many small buildings; e.g. detached houses than in areas with a few much larger buildings; e.g. blocks of flats, because each connection to a single-family house is quite expensive. In the goal to find the ways how to reduce CO