1. Introduction
Rural microgrid designers commonly rely on rule-of-thumb oversizing to guard against resource variability, which inflates capital cost unnecessarily, whereas formal optimisation against a defined reliability metric can identify lower-cost configurations meeting the same service-level target.
2. Methodology
A techno-economic model of an islanded PV-wind-battery microgrid serving a rural community hourly load profile was developed, with particle swarm optimisation applied to search the PV capacity, wind turbine count and battery capacity design space to minimise life-cycle cost subject to a loss-of-power-supply probability constraint of 2 percent, using a full year of hourly measured solar irradiance and wind speed data for the target site.
3. Results
The PSO-optimised configuration achieved a life-cycle cost 16 percent lower than a conventional rule-of-thumb sizing baseline sized to the same 2 percent loss-of-power-supply target, primarily through a more balanced PV-to-wind capacity ratio that better matched the site complementary seasonal resource pattern, validated by full-year hourly simulation against the measured resource dataset.
4. Conclusion
Formal optimisation-based sizing meaningfully reduces life-cycle cost for rural hybrid microgrids relative to conventional rule-of-thumb approaches while maintaining equivalent reliability targets. Future work will incorporate battery degradation modelling into the life-cycle cost objective.
References
[1] Kennedy J. and Eberhart R., Particle swarm optimization, IEEE ICNN, 1995. [2] Bhandari B. et al., Optimization of hybrid renewable energy power systems: A review, International Journal of Precision Engineering and Manufacturing-Green Technology, 2015.