Improving the energy efficiency of lighting systems for a marine equipment manufacturing plant through retrofitting, daylighting, and behaviour change

As the emissions from the operation phase of ship's life cycle are reduced as a result of ongoing efforts, it is anticipated that the decarbonization of ship's manufacturing phase will gain more attention. Marine equipment manufacturing plants are highly energy-intensive and environmentally polluting segments of the shipbuilding industry, necessitating special consideration for environmental issues such as climate change. Through energy-efficient lighting, this study aims to contribute to the promotion of clean production and energy management cultures in marine equipment manufacturing plants. An energy audit was conducted on the lighting systems of a marine equipment manufacturing plant based on the holistic consideration of the following key energy-saving measures: energy-efficiency retrofitting, daylighting, and behaviour change. The daylighting application for the foundry sections of the plant offered an 80% reduction annually in the entire plant's energy use for lighting, associated costs, CO2 emissions, and external costs, along with an initial investment cost (IIC) of €35.480, a net present value (NPV) of €184.322,6, a benefit-to-cost (B/C) ratio of 3.7, and a discounted payback period (DPP) of 2.1 years. However, the proposed daylighting system was found to provide excessive and non-uniform illuminance in the workspaces during the summer days. On the other hand, LED technology satisfied the requirements for illuminance levels and uniformity. The LED application offered a 60.6% reduction in the entire plant's lighting energy use, with an IIC of around €17.052, a NPV of €153.375, a B/C of 3.5, and a DPP of 1.25 years. The plant's carbon emissions can be reduced by about 33 tons annually, while approximately €108.111 in external health costs per year could be avoided. Additionally, around a 3.2% reduction in overall energy consumption with associated benefits can be achieved through energy-efficient behaviour by the employees.