The Optimisation of Energy Systems By Using 3e Factor: the Case Studies

Energy systems should be analysed according to principles of sustainable development. The optimality of technical systems usually is evaluated by only technical and economical criteria. But the estimation of these criteria is not comprehensive enough in the case when system life cycle is much longer than the period of reliable economical prognosis. In this paper the criteria set of energy system evaluation and optimisation was expanded by energy and ecological standpoints and a new multiple criteria indicator (3E factor ‐ Energy, Economy, Ecology) was introduced. The application of this factor was demonstrated by two examples: optimisation of the district heating network pipeline replacement periodicity and optimisation of the thermal insulation of the single family house.