On-site energy generation and on-site energy use are compared to conclude if a building is net zero energy or not.  Net zero site energy buildings are synonymous with site energy metric.

Site energy used in a building is the energy mentioned on the utility bills or meter readings. Electricity generated from captive power generation or cogeneration systems should be added to site energy use.   In India, site energy can be exclusively measured in kilowatt hours or kWh. Most buildings only use electricity for operations with a few exceptions in industrial or commercial buildings which use natural gas and oil.

While less complex than other metrics for calculating energy balances, variances in efficiency of source various fuels and pollution caused by them cannot be captured while using site energy metric. Its scope does not extend to measuring and compensating building energy footprint beyond the site.