Self-Consumption Optimisation and Energy Yield of a 23.4 kWp Grid-Connected PV-BESS System in a Tropical Commercial Environment

The deployment of solar photovoltaic (PV) systems in commercial settings presents distinct technical challenges associated with load profile variability, self-consumption optimisation, and grid interaction dynamics. This study investigates the physical performance and energy yield characteristics of a 23.4 kWp grid-connected PV system with optional battery energy storage system (BESS) integration, installed at a commercial food-service premises in Kuala Lumpur, Malaysia. The system is assessed under the tropical irradiance conditions of peninsular Malaysia, where high solar insolation levels and consistent irradiance patterns create favourable conditions for PV energy generation. Simulation and modelling results indicate an annual energy yield of 28,185 kWh/year (2,317 kWh/month), corresponding to a 19% reduction in grid energy demand at the site. The BESS configuration is evaluated for its capacity to increase self-consumption ratios to 80-90%, reduce grid dependence, and buffer demand-supply mismatches arising from non-coincident solar generation and peak commercial load periods. System degradation modelling over a 30-year operational horizon is incorporated to assess long-term yield stability under fixed Malaysian grid tariff conditions. The findings establish a technical performance baseline for SELCO (Self-Consumption Solar) PV deployments in the tropical commercial sector, contributing empirical energy yield and system behaviour data relevant to Malaysia's 70% renewable energy target by 2050.