Globally 1.5 billion people do not have access to modern electricity supply, and in Ethiopia this is true for an estimated 86% of the population. In the right context, locally manufactured small wind turbines (LMSWT) can provide a low cost, low carbon source of off grid power for rural electrification projects. The locally manufactured aspect of the technology builds the in-country value chain, with component parts being purchased from local markets; it also has the potential to create local jobs and develop local economies having wider benefits to a developing country than just the electricity it provides.
This study has investigated the implementation of LMSWT in Ethiopia for productive use of energy purposes. Optimisation software HOMER has been used to model LMSWT in hybrid systems with solar PV and diesel generators, to provide energy for a typical commercial centre in Ethiopia. System costs and associated manufacturing, installation and business costs were found during primary fieldwork research in Ethiopia. A range of wind and solar resource data used for the study were obtained from the International Renewable Energy Association, analysed and compared to studies from available literature.
HOMER uses all given parameter values to output optimal systems in terms of lowest Levelised Cost of Energy and Net Present Cost for given solar and wind resources. The resulting surface plot shows that it is competitive to include LMSWT in an off grid system for any solar resource in Ethiopia, when the wind speed is 5.5m/s or above. The operation and maintenance cost multiplier, based on the distance between installation site and location of service centre, indicates that when service technicians have to travel more than 7 hours to a site, it is uneconomical to include LMSWT in the system.
The HOMER surface plot was used with GIS software to plot, on a grid layout of a national map of Ethiopia, the most cost effective system configuration given the wind and solar resource in that area. Additional GIS analysis was included such as national electricity, population and protected areas. It was found that for the majority of the country, solar PV/Generator systems (without LMSWT) are suitable. However in the South and East of Ethiopia high wind speeds make it competitive to include LMSWT in a hybrid system with solar PV, and in a limited number of locations a LMSWT/Generator system is most optimal. It was found that ideal locations for LMSWT implementation correspond to areas not currently connected to the national grid, with low population and also areas of high risk of civil unrest.