Abstract Trinidad and Tobago possesses high solar energy potential yet continues to rely almost entirely on natural gas for electricity generation. Residential adoption of solar photovoltaic (PV) systems remains minimal, largely due to uncertainty about costs, savings, and long-term financial viability. This study develops and applies a localized life cycle cost analysis (LCCA) model for residential solar (PV) systems, designed to quantify the total cost of ownership, including installation, maintenance, and replacement while accounting for energy savings, inflation, and policy incentives. Using a mixed-methods design, primary cost and performance data were obtained through semi-structured interviews with leading industry practitioners, complemented by secondary data from government reports and academic studies. Quantitative analysis was conducted for three system sizes (3 kW, 6 kW, 10 kW) over a 25-year operational period, incorporating Monte Carlo simulations and sensitivity testing to assess uncertainty. Results indicate that the 6-kW configuration achieves the lowest life-cycle cost (TT 38, 566 per kW) and a payback period of approximately 29 years, which shortens to 15–16 years under projected tariff increases. Net Present Value and Internal Rate of Return analyses confirm that current residential tariffs render PV systems financially unattractive without targeted policy support. The findings highlight the need for structured incentives such as feed-in tariffs, concessional financing, and tax credits to promote household-level solar adoption in Trinidad and Tobago. This study has created the first probabilistic LCCA for residential (PV) systems in Trinidad and Tobago, offering policy guidance for other small-island developing states (SIDS).
Roberts et al. (Thu,) studied this question.