Comparative efficiency analysis of monocrystalline and polycrystalline solar panels under tropical climate conditions

Which photovoltaic technology delivers superior performance under the demanding conditions of tropical climates? This research compares monocrystalline and polycrystalline solar panel efficiency and energy yield under Malaysian equatorial conditions characterized by high temperatures, intense humidity, and variable cloud cover patterns. The investigation monitored matched panel arrays over a complete annual cycle to capture seasonal variations and establish performance expectations for solar installations throughout the tropical Southeast Asian region [1]. The experimental program was conducted at the Kuala Lumpur Institute of Technology renewable energy research facility from January through December 2024, employing parallel monitoring of identical-capacity monocrystalline and polycrystalline arrays under identical environmental exposure. Continuous data acquisition recorded electrical output, irradiance levels, ambient temperature, module temperature, and humidity at five-minute intervals throughout the monitoring period. Results demonstrated that monocrystalline panels achieved 12.5% higher annual energy yield compared to polycrystalline alternatives despite both technologies experiencing significant efficiency derating under tropical conditions. Monocrystalline arrays delivered average efficiency of 16.2% compared to nameplate rating of 21.3%, while polycrystalline arrays achieved 14.1% efficiency against 17.8% rated specification. The efficiency gap between technologies remained relatively consistent across seasons, though both experienced minimum performance during the hot humid period from April through September. Thermal losses emerged as the dominant performance limitation, with module temperatures regularly exceeding 55 degrees Celsius during peak irradiance periods. The temperature coefficient disadvantage of monocrystalline silicon produced greater absolute efficiency reduction, yet higher baseline efficiency maintained overall performance advantage. Soiling losses averaging 2.4% required bi-weekly cleaning intervention to maintain near-optimal output. The findings support continued preference for monocrystalline technology in space-constrained Malaysian installations despite higher initial cost, while polycrystalline panels remain economically attractive for larger ground-mounted systems where area availability reduces the premium on conversion efficiency. Annual energy yield projections of 1,322 kWh per kilowatt-peak for monocrystalline and 1,175 kWh per kilowatt-peak for polycrystalline arrays provide planning guidance for solar system sizing in tropical climates.