Rural isolated mini-grid with photovoltaic supply in Chifunda (Zambia)

Abstract

The energy demand in developing countries is increasing and many villages in these countries do not even have a connection to the national grid. Therefore, they use kerosene and candles for lighting their homes at night and batteries for supplying their electrical devices. With renewable energy sources a minigrid can be built up anywhere to cover the demands. The village in which the project will be conducted is near the equator and therefore a photovoltaic system provides a good opportunity for the energy supply. This thesis approaches the whole planning for an electrification of a village in Zambia, which is called Chifunda. In this area about four-hundred households need to be supplied and also the demands of other buildings like a mill, a school, a hospital and different shops need to be covered. Nearly the whole energy will be supplied by the photovoltaic- and the storage system, but a small part still need to be covered by a backup generator. The demand of the village is predefined and so there will be two options introduced. First, the needs are reduced to the essential parts and the system will be calculated to supply this amount of energy. The second option is to cover nearly the whole energy needs with the photovoltaic- and the storage system. For the whole planning of the electrification the dimensioning of the system parameters is important and also the electrical protection of the system has a significant role. The whole calculations and analysis have been done with the program PVsyst. For the calculation of the storage system, it was necessary to export different data to Excel. Therefore, a program had to be written which can compute the state of charge of the battery, the energy which is needed from an external source and the lost energy which is due to a full battery. With the help of this program it was possible to calculate if the sizing of the system was sufficient. Therefore, the different options have been compared and analysed to get the cheapest and most sustainable solution.