Models for probabilistic power transmission system reliability calculation.

In Denmark many independent power producers such as windmills and small gas- or oil fuelled combined heat and power plants (below 50 MW) have been set up in the last few years. Further, the larger power plants in Denmark are combined power plants with heat production to district heating. Understanding of this complex utility system with regard to cost and reliability are to be examined by a probabilistic network planning program, which can take into account all these specialities for the Danish network and include probabilistic models for the load and for the transmission system as well. Such a program have been set up with stochastic models of the windmills, the loads, the small combined heat and power plants and the heat production from the larger power plants. The models are used on a realistic network grid, and Monte-Carlo simulations are used in the final simulation program.