08-16-2017, 09:40 PM
Electric energy consumption is the form of energy consumption that uses electric energy. Electric energy consumption is the actual energy demand made on existing electricity supply.
Consumption of electric energy is measured in watt-hours (written W h, equal to watts x hours)
1 W h = 3600 joule = 859.8 calorie.
Electric and electronic devices consume electric energy to generate desired output (i.e., light, heat, motion, etc.). During operation, some part of the energy depending on the electrical efficiency is consumed in unintended output, such as waste heat.
Electricity has been generated in power stations since 1882. The invention of the steam turbine in 1883 to drive the electric generator started a strong increase of world electricity consumption.
In 2008, the world total of electricity production was 20,279 terawatt-hours (TWh). This number corresponds to an average rate of around 2.3 terawatts continuously during the year. The total energy needed to produce this power is roughly a factor 2 to 3 higher because a power plants' efficiency of generating electricity is roughly 30 50%. The generated power is thus in the order of 5 TW. This is approximately a third of the total energy consumption of 15 TW (see world energy consumption).
In 2005, the primary energy used to generate electricity was 41.60 Quadrillion BTU (Coal 21.01 quads, Natural Gas 6.69 quads, Petroleum 1.32 quads, Nuclear electric power 8.13 quads, Renewable energy 4.23 quads respectively). The gross generation of electricity in that year was 14.50 Quads; the difference, 27.10 Quads, was conversion losses. Among all electricity, 4.84 Quads was used in residential area, 4.32 Quads used in commercial, 3.47 Quads used in industrial and 0.03 Quads used in transportation. 1 Quad = 1.055 Exajoule.
16,816 TWh (83%) of electric energy was consumed by final users. The difference of 3,464 TWh (17%) was consumed in the process of generating power and lost in transmission to end users.
A sensitivity analysis on an adaptive neuro-fuzzy network model for electric demand estimation shows that employment is the most critical factor influencing electrical consumption. The study used six parameters as input data, employment, GDP, dwelling, population, HDD and CDD, with electricity demand as output variable.
