Off-grid renewable energy grids will contribute to the achievement of SDG 7 on universal energy access, especially in off-grid communities. But the scarcity of resources for development aid requires very tight designs that minimize the cost of investment and operation of the mini-grid. To do this, the future energy demand of the community must be analysed very well, which is very difficult due to the lack of previous data. In the literature, two main approaches to analyse future energy demand, deterministic and stochastic methodologies. In this article, we compare both methodologies for a real case study in Honduras and discuss their advantages and disadvantages. Although the deterministic approach requires less information and less mathematical processing, it generates less accurate results. In contrast, the stochastic approach consumes more resources but gives more realistic results for the correct design of the mini-grid. In conclusion, the deterministic approach methods can be useful for the early stages of the project, when the investment is being sized. But for the advanced phases of the project, when the installation is being designed, the stochastic approach is recommended.@en

Off grid electrification is key to achieving universal electricity access. Despite the potential of biomass gasifiers as a clean technology to ensure reliable systems, they are not as well looked upon as their advantages suggest. In particular, the software HOMER, which researchers and technicians use the most to simulate and design Microgrids, does not include biomass gasification among its simulation technologies. Although some authors did simulate biomass gasifiers in HOMER, the necessary parameters and procedures to calculate and include them in the tool remain unclear, non-replicable, and leave open research questions as regards modelling. Using the inbuilt Biogas power plant modules in HOMER, this paper presents a set of steps to include the technical and economic parameters to simulate fuelling an electric generator through the syngas produced in a downdraft biomass gasification plant. Two case studies of isolated rural communities in Honduras and Zambia show the viability of the procedure. These case studies also confirm the technical and economic viability of islanded biomass-photovoltaic hybrid renewable energy microgrids. In both cases, the energy demand supplied and distributed by the microgrid had a Levelized Cost of Energy lower than the alternative of extending the electric grid to the communities.@en