Approach for flexible and adaptive distribution and transformation design in rural electrification and its implications

Abstract

Microgrids have an important role to play in achieving current international targets of electrifying poor rural communities around the world. In the East-African context, microgrid developers face challenges related to dispersed settlement patterns and high poverty levels that prevent many rural citizens from affording grid connections. Contextual factors influence demand for electricity, leading to uncertainties regarding development of consumption in newly electrified areas. Developers struggle with the sizing of microgrids and often initially oversize the system in anticipation of growing demand, which leads to significant investment costs and economic risk in case projected growth fails to appear. Our focus in this paper is to introduce an approach for flexible and adaptive distribution design – a process that can reduce initial investment cost and still be able to meet the long-term variations of the load in a controlled manner, thereby removing an entry barrier related to microgrid development. We exemplify the usefulness of this design approach in three different application areas: distribution capacity, transformation capacity and level of protection systems. Each application area consists of a number of steps based on mature technologies that correspond to change in capacity. The steps can be taken in sequence or in part, to achieve a system configuration adaptive enough to handle changes in electricity consumption, both increasing and, in some cases, also decreasing. Considerations on how steps would impact on system operation, power transfer capacity and demands on local technical expertise and maintenance are included. Importantly, the technical discussion details socio-economic aspects and the consequences for end-users as well as the utility. We exemplify the feasibility of the approach and provide a context for the discussion using real-world examples from East Africa.