The literature adopts the method of life cycle calculation of carbon footprint, specifies the carbon emission sources in the four stages of the life cycle of this 110kV substation scheme: the preparation stage, the construction stage, the operation stage and the end-of-life stage, determines the carbon emission factors and engineering data, and calculates the carbon footprints of each stage. Users of this LCA data set should ensure they apply it specifically to the construction and operation of indoor medium to high voltage substations, especially those employing environmentally friendly technologies such as non-SF6 GIS. Care should be taken when extrapolating this data to ensure regional specificities, such as local carbon emission factors and technological applicability, are properly accounted for. For construction phase modeling, aspects like the planned number of transformers, busbar configuration, type of switchgear, and inclusion of shunt capacitors and reactors should be reflected. The service life assumed should be verified for alignment with the 50-year validity period used in this data set. During operation phase assessment, consideration of the environmentally friendly products and absence of SF6 equipment alongside operational inputs/outputs should be included. Users must obtain more recent and location-specific emission factors as part of their LCA study.