How many trees are required to offset the CO2 emissions from building operations? A case study of energy efficiency initiatives in Wisma R&D, Universiti Malaya building

Malaysia has pledged to GHG emissions by 45% by 2030 in light of the urgent need to reduce global emissions. One approach used by the government is to concentrate on energy sustainability programs, such as energy efficiency (EE). The success of this approach relies on the support from various parties. Persuading non-technical management and staff, however, might be particularly difficult. Hence, besides the technical-based impact, it is important to analyse the environmental and financial-based impact too. This paper portrayed the EE initiatives that could assist in reducing energy (kWh), cost (RM), and CO2 (tonne) simultaneously. The number of trees needed to neutralise or offset an emission might later be related to a reduction in CO2. A case study of Wisma R&D, UM was referred. The environmental-based impact of the lighting retrofitting projects at Wisma R&D was used in this study to illustrate the importance of EE approaches. Both parameters are obtained from the online Greentech carbon calculator. A 144,386 kWh annual savings resulted in RM 52,701 in cost savings, and a decrease of 100.2 tonnes of CO2 emissions was achieved. Ultimately, based on the decrease in CO2, 2569 fewer trees are needed to offset the emission.