Modelling temporal diffusion of PV mircogeneration systems in a rural developing community

Development of electricity delivery infrastructures are path-dependent, meaning, each development decision and step affects subsequent steps, and the final outcome. Human actors are therefore the most important variables in any energy development plan as their decisions affect the way a system evolves. Proper policy-planning tools are therefore required to guide decision-makers on least-cost rural electrification topologies. Many factors influence choices of technologies used in rural electrification, the main ones being availability of resources, availability of necessary technical infrastructures, demand, investment costs, and local socio-political and cultural environments. Different modelling tools and techniques have been applied in planning rural electrification paths in many developing countries. However, these often view this problem as a question of expansion of grid coverage through extensions of existing transmission and distribution lines from central power generation stations and seldom address the unique and regionally-specific challenges presented by each developing nation. To the best of our knowledge, no work has captured, in one study, the unique socio-economic, cultural and political environments, and market and technical infrastructural challenges presented by different rural communities in developing nations. In this work decentralized power systems based on locally available renewable energy resources, in this case solar, are explored as cost-effective electrification alternatives to national utility grid extensions to rural developing communities. An agent-based model (ABM) is developed in Netlogo to provide decision-makers with a user-friendly tool for PV-based rural electrification policy development, planning, and implementation. The model takes into account the complexities and limitations of solar electricity microgeneration technologies, decisions by human actors, geographical factors, and interactions between the three factors in order to capture the overall macro-effects of different micro-decisions in a virtual world; ABMs seek to model individual entities within a complex system and the rules that govern the interactions of the entities within the system, to capture the overall effect of such interactions. The novelty of the model developed in this work is that it simultaneously simulates how technical, socio-economic, and political factors affect temporal diffusion of PV microgeneration systems in a typical rural developing community. The model further simulates how households with PV, driven by demand for more power and other factors, come together to form communal grids. Survey data from Kendu Bay area of Kenya are used to inform the model. Empirical data provided by the Kenyan government are used to validate the model. The model developed in this work could be used by developing nations in their rural electrification planning and implementations, and a test-implementation funded by the Kenyan government is currently underway. Results show that given various electrification options, households in rural developing communities would overwhelmingly choose small PV microgeneration systems as stepping stones to future grid electrification. This is mainly due to initial basic electricity needs, rapidly falling PV costs, and affordability of such small PV systems; these small PV microgeneration systems allow households to enjoy the benefits of electricity with modest investments while also allowing future modifications with increasing household incomes, increasing power demands, and changing technologies. Another key finding of this research is that as their power demands increase beyond what could be fulfilled by small stand-alone PV systems, most rural households opt for PV-based communal grids as opposed to connecting to the national grids due to low cost, control over a community’s own power source, increased reliability and availability, and security of power source. Results also show that increased PV installations, and correspondingly more connections to communal grids, could be realized with introduction of favourable government policies such as subsidies, introduction of favourable microcredit facilities, increased social pressure through advertisements and neighbourhood influence. Furthermore, results indicate that, based on control methods and architectures, start-up and maintenance and operations costs of communal grids could be minimized and thus become more attractive to would be consumers, compared to the national grids.