Impact of Energy Efficient Lighting on Overall Energy Use Intensity in Commercial Buildings: a Case Study of Co-op House

Abstract

Energy efficiency is key for organizations that are keen on managing their energy costs. Lighting is one of the low hanging fruits, commonly recommended in energy audit reports, that buildings can implement to achieve savings. However, to fully understand the energy savings potential of buildings proper computation of savings is important. This study sought to quantify the savings potential for efficient lighting in buildings in kilowatt-hours energy savings and improvement in Energy Use Intensity for Co-op House. A literature review of energy efficiency in buildings was done to understand the progress made in the subject matter and the research gaps that exist. Data for the study was collected by the administration of a structured questionnaires that required the energy manager to fill in details on their high-rate energy consumption, low-rate energy consumption, demand in kilowatt and kilovolt-Amperes, power factor as well as the utility bill in monetary terms. An inventory of the existing lighting was taken, detailing the type of fixtures, type of lamps, energy consumption per fixture as well as hours of use. The data was then tabulated and analyzed through Excel sheet. In 2020, The overall Energy Use Intensity averaged at 296 kilowatt-hours per square meter per year against the recommended benchmark of 226 kilowatt-hours per square meter per year. Lighting had an Energy Use Intensity of 124 kilowatt-hours per square meter per year, against the recommended value of 54 kilowatt-hours per square meter per year for a typical office. The analysis showed that replacement of all fluorescent lights with LED equivalent would contribute to 18.3 % improvement in the Energy Use Intensity. It is recommended that the facility replaces the existing fluorescent tubes with LED lighting. This project has a simple payback of 1.7 years and has a positive Net Present Value and is therefore economically viable for implementation.