Optimisation model for decentralised power system planning

The availability of energy is considered to be the primary prerequisite for any economic development in the countries of the Third World. This applies especially in the rural areas, where the shortage of energy leads to an uncontrolled exploitation of the natural sources of energy. The lack of commercial energy sources not only hinders economic development, but also goes a long way towards destroying the ecological balance of nature and the basic living conditions. The future development of the electricity supply system is looked upon as being the solution to the energy problems in the rural areas. The utilisation of hydropower as being a proven and environmentally acceptable technology is again becoming increasingly important. The structure of the settlements in the rural areas favours the application of decentralised supply systems with small power station units. The economic demands made on the design of decentralised electricity supply systems call for the use of a planning instrument which is able to cope with the complex problems. Efficient and field-proven optimisation and simulation models have been developed to optimise the design and operation of supra-regional, thermic-oriented power supply systems. However, the structural pre-requisites of large supply networks differ greatly in their characteristics from decentralised, hydropower-oriented systems which supply electricity in the rural areas of the developing countries. Basically, two significant structural prerequisites of large, supra-regional power station systems justify simplified assumptions adopted in the afore-mentioned models. Firstly, there is a closed system of power stations and load centres and secondly, the costs for the power generation components are very high, compared to those for the power transmission components. By way of,contrast, electricity supply systems, in rural areas of developing countries, are characterised as: widely scattered load centres with a comparatively low demand, low load factors and short-term high peak loads on the part of the consumers, few existing power plants and transmission lines, high cost quota for the transmission elements.