Energy-Efficient Retrofitting of Buildings in the Tropics Through Daylight and Solar Radiation Harnessing

Retrofitting existing buildings in tropical regions, which comprise a substantial portion of the global population, has become a crucial focus in response to the pressing global energy crisis. Tropical areas face unique challenges in achieving comfort and energy efficiency due to high levels of solar radiation, temperature, humidity, and very low wind speed. In light of the growing population and energy demand in tropical areas, it is paramount to address these challenges by harnessing daylight and solar radiation, thereby reducing energy consumption in buildings. This study focuses on a case analysis of retrofitting a building in Trivandrum, India, to reduce energy consumption by implementing light pipes as a daylighting strategy complementing the strategy with energy harnessing using PV panels. The analysis evaluates the energy efficiency of this approach and calculates the payback period, offering insights into the retrofitting of existing building stock in tropical countries. The study demonstrates that the PV panels offer a swift 3-year ROI, totaling (sic)92,40,000 over 25 years from a (sic)11,70,400 investment. They also cut CO2 emissions by 947 tonnes, akin to planting 1515 teak trees, aligning with SDGs 11 and 12 i.e., to promote sustainable communities and to reduce consumption and production. Similarly, Light Pipes incur a (sic)2,34,408 installation cost and a (sic)3,69,600 payback over 25 years. They reduce 2.685 tonnes of CO2 emissions annually, like planting 107 Teak trees, demonstrating environmental sustainability and resource efficiency. The findings of the research contribute to informed decision-making, promote energy efficiency, help reduce carbon emissions and enhance sustainability.