Assessment of costs and benefits of green retrofit technologies: Case study of hotel buildings in Sri Lanka

With the rising impact of greenhouse gas emissions, resource depletion, and the global interest in sustainability advancements within all sectors, construction industry practitioners are also interested in incorporating sustainable features and practices into their buildings. Nevertheless, most of the commercial buildings in Sri Lanka had been constructed during the unprecedented urbanization between 1995 and 2010, thus, before sustainable concepts became more prominent. Therefore, existing buildings in Sri Lanka is experiencing ever-increasing energy consumption, resulting in higher utility costs, with which green retrofitting has become imperative, notably in hotel buildings. This study, therefore, conducted an economic evaluation of three existing hotel buildings to establish an account of the cost implications and saving potentials of different green retrofit technologies. The data collected through document reviews and site visits were analysed using net present value and simple payback period calculations. Although number of retrofitting technologies have been incorporated in the selected buildings, more weight has been given to incorporating technologies to achieve energy efficiency and indoor environmental quality. Considering the financial viability, all the implemented green retrofits have a positive return on investment and less than ten years of payback period, except LED televisions. Amongst the implemented retrofits, biomass boilers, energy-efficient chillers, and solar PV systems have the highest energy-saving efficiency, followed by VFDs and LED lighting, while LED televisions have the lowest. The study's findings contribute to industry practitioners identifying the appropriate green retrofits based on the cost implications and savings potential and enhancing the sustainability of the built environments by reducing greenhouse gas emissions and depletion of natural resources.