Charles Kofi Kafui Sekyere

The limited adoption of solar photovoltaic (PV) energy within Ghana’s private sector presents a barrier to the broader implementation of renewable energy technologies. This challenge is driven by insufficient empirical data on the operational performance and economic benefits of solar PV systems to inform business investment decisions. This study bridges this gap through a techno-economic assessment of two small scale grid-tied solar PV systems installed for a hotel and a financial institution. Solar energy production data from January to December 2023, combined with PVSyst software simulations and a spreadsheet model, were used to evaluate the technical performance and financial viability of the systems. The hotel’s solar with a capacity of 38.22 kWp delivered an annual energy output of 45,880 kWh, a specific yield of 1,200 kWh/kWp/year, a performance ratio of 62%, a Levelized Cost of Energy (LCOE) of 0.065 USD/kWh, and a payback period of 6.55 years. In comparison, the financial institution’s system which has a capacity of 20.68 kWp generated 13,720 kWh annually, with a yield of 663 kWh/kWp/year, a performance ratio of 34%, an LCOE of 0.12 USD/kWh, and a payback period of 13.53 years. Simulating the integration of battery storage for the financial institution solar improved the technical performance raising annual generation to 21,213 KWh, yield to 1,025 kWh/kWp/year, and performance ratio to 52%. However, this increased the LCOE to 0.14 USD/kWh and extended the payback period to 15 years. Further analysis of net metering integration showed enhanced performance and more favorable financial outcomes for both systems. By analyzing real operational data of existing solar systems and exploring optimization options across two different private sector organizations, this study provides practical insights into the interventions required to encourage the adoption of solar PV energy by private enterprises in Ghana.

C-Si solar cell interconnection damages from thermal cycles emanate from cumulative damage contributions from the various load steps in a typical thermal cycle. In general, a typical thermal cycle involves five thermal load steps, namely: 1st cold dwell, ramp-up, hot dwell, ramp-down, and 2nd cold dwell. To predict the contributions of each of these load steps to creep damage in soldered interconnections, each of the respective load steps needs to be profiled to accurately fit a function capable of predicting the damage contributions from a given number of thermal cycles. In this study, a field thermal cycle profile generated from in situ thermal cyclings at a test site in Kumasi, a hot humid region of sub-Saharan Africa, is used to predict damage in solar cell interconnections from accumulated creep energy density using finite element analysis (FEA). The damage was assessed for two different solder formulations, namely: Pb₆₀Sn₄₀ and Sn_3.8Ag_0.7Cu (lead-free). The results from the FEA simulations show that the cooling (ramp-down) load steps accounted for the highest accumulated creep energy density (ACED) damage in solder interconnections. The ramp-up load steps followed this closely. The cumulative contributions of the two load steps accounted for 78% and 88% of the total damage per cycle in the Pb₆₀Sn₄₀ and Sn_3.8Ag_0.7Cu solder interconnections, respectively. Furthermore, a study of the damage profiles from each of the five load steps revealed that each of the damage functions from the various load steps is a step function involving the first two thermal cycles, on one hand, and the remaining 10 thermal cycles on the other hand. The damage from the first two thermal cycles can be predicted from a logarithmic function, whereas the damage from the remaining 10 thermal cycles is predicted using six-order polynomial functions. The ACED results computed from the damage functions are in close agreement with the results from the FEA simulation. The functions generated provide useful relations for the prediction of the life (number of cycles to failure) of solder interconnections in solar cells. The systematic approach used in this study can be repeated for other test sites to generate damage functions for the prediction of the life of c-Si PV cells with SnPb and lead-free solder interconnections.

Coconut husks with the shells attached are potential bioenergy resources for fuel-constrained communities in Ghana. In spite of their energy potential, coconut husks and shells are thrown away or burned raw resulting in poor sanitation and environmental pollution. This study focuses on quantifying the waste proportions, calorific values and pollutant emissions from the burning of raw uncharred and charred coconut wastes in Ghana. Fifty fresh coconuts were randomly sampled, fresh coconut waste samples were sun-dried up to 18 days, and a top-lit updraft biochar unit was used to produce biochar for the study. The heat contents of the coconut waste samples and emissions were determined. From the results, 62–65% of the whole coconut fruit can be generated as wastes. The calorific value of charred coconut wastes was 42% higher than the uncharred coconut wastes. PM_2.5 and CO emissions were higher than the WHO 24 h air quality guidelines (AQG) value at 25 °C, 1 atmosphere, but the CO concentrations met the WHO standards based on exposure time of 15 min to 8 h. Thus, to effectively utilise coconut wastes as sustainable bioresource-based fuel in Ghana, there is the need to switch from open burning to biocharing in a controlled system to maximise the calorific value and minimise smoke emissions.