This degree project investigated the potential for electrifying working machines used in energy infrastructure projects together with Omexom. The study focused on excavators, dump trucks and crane trucks and compared diesel and electric alternatives from a technical, environmental and economic perspective. The work included literature studies, supplier communication, charging simulations for an electric excavator (EWR150) and a field test with an electric dump truck. Three project scenarios representing different project sizes were also analyzed. The results showed that electric machines reduce tank-to-wheel CO₂ emissions compared with diesel machines. The electric alternatives also showed lower equivalent energy demand because of the higher efficiency of electric machines. However, the study also identified practical limitations related to charging infrastructure, battery capacity, machine availability and current leasing conditions. Among the evaluated machines, the excavator appeared to be the most suitable machine to electrify first because it is one of the most used machines, has less movement therefore more efficient, it operates within the project site and easier charging possibilities during the workday. Overall, the study shows that electrification of working machinery within energy infrastructure projects is already possible today, but successful implementation still depends on project conditions, charging possibilities and future market development.