Modelling Integrated Biomass and Photovoltaic Generators for Rural Electrification

Renewable energy technologies can be used for clean electricity generation, rapid rural electrification and cost-effective supply of reliable electricity. In this thesis, the study of the effect of integrating biomass and photovoltaic generators for rural electrification will involve survey and modelling of rural households load profiles, investigation of the optimal combination of PV, biomass and battery energy systems for reliable supply of electricity and a power flow study of the impact of load aggregation on the operation of a regional grid. The studied location solar radiation and biomass availability data are used when selecting the optimal combination of components in the hybrid renewable energy system (HRES) design space.
An occupancy-based stochastic load profile model is developed with the use of survey data on the number of bedrooms in a household, household population and classification, occupant’ activity schedule and appliance ownership. Analysis of simulated load profiles show that the studied location average daily energy consumption was 3.13 kWh. During solar radiation assessment, performance evaluation of meteorological parameters used for constructing solar radiation estimation models show that temperature is an important meteorological parameter that should be used to estimate studied location solar radiation. Whilst, the minimum required duration of measured data to estimate past solar radiation shows that 2 years of recent data is required to achieve R2 greater than 0.75, and more than 5 years of recent solar radiation data is required to achieve R2 greater than 0.9. Biomass availability assessment shows that the quantity of recoverable household and animal bio-waste in the studied location is limited. To reduce the quantity of outsourced bio-waste and minimize anaerobic digester volume, biogas generator is only used when energy demand is greater than 50% of its rated capacity. Study on how different combinations of PV, biogas generator and battery systems affect the optimal sizing of battery shows that an optimally designed HRES requires a much smaller battery capacity than when a biogas generator and battery or a PV and battery are integrated for rural electrification in the studied location.
Techno-economic analysis of the HRES shows that for 0% loss of power supply probability (LPSP), the levelized cost of energy (LCOE) is $0.1657/kWh, but the LCOE for a diesel alone energy system was $0.62/kWh. Despite the national grid unreliability, its 2019 residential customers reflective tariff (i.e., a tariff without subsidizes) for the studied location was $0.164/kWh. HRES analysis also shows that if the HRES LPSP is increased to 3.7%, its LCOE is reduced to $0.1623/kWh. So, for a LPSP of 3.7%, the HRES LCOE is less than the LCOE of the national grid. Power flow study of the effect of aggregating 5 regional loads show that load aggregation reduced the 5 regions peak load by 23%. Furthermore, power flow study of the regional grid shows that power losses minimization will be achieved when installed generators are not centralized but distributed in terms of the amount of apparent power drawn by each of the regional grid load buses. Overall, this study shows that integrated biomass and photovoltaic generators can be used for rural electrification because the HRES guarantees the supply of clean and sustainable electricity and its LCOE can compete with national grid LCOE. Meanwhile, future work will profit from the development of an electricity pricing plan that allows for the shifting of peak loads and a study of how the electricity pricing plan affects LCOE.