Primary energy is the total energy contained in a raw source before it is converted into consumable energy or used as a feedstock for products like plastics. For example, primary oil energy demand refers to the energy content of crude oil before it is refined into fuel or used in industrial applications. Primary energy is greater than final energy consumption because it accounts for inefficiencies in fuel processing, thermal conversion, and transmission and distribution (T&D).
Final consumption refers to the total energy consumed to meet the demand of all final energy uses plus the use of feedstocks for products like plastics. For example, how much electricity a lightbulb uses or how much fuel a truck burns are measures of final energy consumption. It does not include energy lost through transmission and distribution (T&D) or inefficiencies, which, in contrast, is accounted for in primary energy.
If you're interested in learning more, this explainer might be helpful: https://energyeducation.ca/encyclopedia/Total_final_consumption
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