Abstract:
Efficiently managing and prioritising the charging of portable electronic devices powered by
solar photovoltaic sources in off-grid and resource-limited environments is a huge problem. Ensuring
that critical devices maintain operational uptime, especially when energy resources are scarce and
in instances where multiple devices compete for charging from the limited solar power available
is crucial. This paper introduces an optimisation framework designed to prioritise the charging of
portable electronic devices powered by solar photovoltaic sources. The approach aims to maximise
operational uptime for critical loads before addressing less essential ones. By strategically allocating
charging priorities based on comprehensive evaluations of battery capacities, usage patterns, and
operational requirements, the optimisation process seeks to enhance overall efficiency and readiness
of portable electronic devices in dynamic, austere and resource-constrained settings. The charging prioritisation problem was solved using MATLAB’s (version number 9.13.0.2193358 (R2022b))
OPTI toolbox in conjuction with the SCIP solver. A case study, involving three portable electronic
devices—a cellphone, GPS and radio, demonstrated the model’s effectiveness in maximising satisfaction by aggregating device priorities over time. The model prioritised charging of the GPS due to its
critical operational role, followed by the radio for its essential communication function, while the
cellphone, with lower usage demands, was assigned the lowest priority. The model developed in this
study is versatile and applicable to diverse demand profiles and any number of portable electronic
devices. Furthermore, it can be customised to operate effectively in various geographic locations,
irrespective of solar radiation levels.
