The nexus of grids, mini-grids and off-grid options for expanding electricity access.
The purpose of this knowledge paper is to present a review of literature on the nexus between grid and off-grid electrification options and the enabling conditions to support each option. Through a thorough review of available academic and practice-oriented literature, this paper provides a synthesis and interpretation of the grid and off-grid electrification debate for electricity access. The paper finds that techno-economic studies do not consider the grid and off-grid alternatives directly and the suggested least-cost off-grid technology combinations generally represent relatively expensive solutions. The recent least-cost electrification planning models have considered the technology choice using geospatial information, but the model outcomes differ significantly due to, for example, granularity of the data used, the technology options considered, input assumptions about demand, economic activities, technology costs, operating costs, discount rates, and project life. More granular spatial data and model capability to capture low voltage distribution infrastructure appear to suggest greater attractiveness of decentralised solutions, whereas more aggregated analysis appears to support grid extension. Similarly, grid extension appears to be the least-cost option for higher demand or for concentrated population clusters, whereas decentralised solutions are more economic in dispersed areas with low demand.