Energy

Final use of energy

How does a country use the annual primary energy sources available? The answer is provided in the second part of the NEB containing data on the finale use of energy. Energy uses include the energy consumption of households and enterprises (of course enterprises producing electric energy to be destined to final uses are excluded). Therefore part of the energy available as a primary source needs to be transformed to be used. As seen before, the most important transformation is the thermoelectric transformation, i.e. fossil fuels becoming electric energy. By moving from primary consumption to the final consumption we see that the composition of energy sources varies because the quantity of fossil fuels decreases and that of electric energy increases. Besides in the composition of energy sources, there is a variation also in the quantity of available energy for final uses. The quantity which can be actually destined to final uses is smaller than the primary energy available because the transformation processes involve consumption and losses. For example, the use of fossil fuels (coal, oil, natural gas) to produce electric energy approximately involves a 60% average loss of the energy originally contained in the fuel. It means that if among the primary sources 100 Tonne of oil equivalent of coal are available to produce electricity, at the final use stage only 40 Tonne of oil equivalent of electric energy will be available. The remaining 60 Tonne of oil equivalent were lost during the electric transformation process and cannot be used by households or industrial plants (final uses). At this stage of the National Energy Balance we have the available energy quantity for the final uses, i.e. the quantity of energy consumed by industries (plants), transports (cars, lorries, trains, buses), citizens (households), agriculture and finally bunkering (the fuel consumption of ships).