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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.
Contents
Overview
Consumption of electric energy is measured in watt-time, or precisely multiples of watt-hours (written W·h, equal to watts x hours) which is the universal measure of Energy,
1 W.h [Watt hour] = 60 Wm [Watt minute] 1 W.m = 60 W.s [Watt second] so, 1 W.h = 60 x 60 W.s = 3600 W.s = 3.6 kWs (kilo Watt second) 1 W.s = 1 Joule Hence, 1 W.h = 3600 Ws = 3600 Joule Also, 1 W.h = 0.860 KCAL (people commonly say KiloCalorie as calorie) 1 kWh = 860 KCAL 1 W·h = 3600 Watt second = 3600 joule = 860.421 KCAL (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) or 20.279 petawatt-hours (PWh). 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 plant's 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 [12, 192 TWh] (Coal 21.01 quads [6,157 TWh], Natural Gas 6.69 quads [1,960 TWh], Petroleum 1.32 quads [387 TWh], Nuclear electric power 8.13 quads [2,383 TWh] , Renewable energy 4.23 quads [1,240 TWh] respectively). The gross generation of electricity in that year was 14.50 Quads [4,250 TWh]; the difference, 27.10 Quads [7,942 TWh], was conversion losses. Among all electricity, 4.84 Quads [1,418 TWh] was used in residential area, 4.32 Quads [1,266 TWh] used in commercial, 3.47 Quads [1,017 TWh] used in industrial and 0.03 Quads [8.79 TWh] used in transportation.
1 Quad = 1 Quadrillion BTU = 1 x 1015 BTU = 293 TWh
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.
World electricity consumption down in 2009
At the world level, energy consumption was cut down by 1.5% during 2009, for the first time since World War II. Except in Asia and Middle East, consumptions were reduced in all the world regions. In OECD countries, accounting for 53% of the total, electricity demand scaled down by more than 4.5% in both Europe and North America while it shrank by above 7% in Japan. Electricity demand also dropped by more than 4.5% in CIS countries, driven by a large cut in Russian consumption. Conversely, in China and India (22% of the world's consumption), electricity consumption continued to rise at a strong pace (+6-7%) to meet energy demand related to high economic growth. In Middle East, growth rate was softened but remained high, just below 4%.
World electricity consumption (2012)
The table lists the top 37 electricity consuming countries, which use 19,000 TWh/a. i.e. 90% of the consumption of all more than 190 countries. The total consumption (including the amount consumed by the power plants) and the energy sources to generate this electricity is given per country. The data are of 2012. The last column contains the number of millions of inhabitants.
Electricity generation and GDP (2009)
Listed countries are top 20 populous countries and/or top 20 GDP (PPP) countries and Saudi Arabia as of CIA World Factbook 2009.
30 countries (exclude EU/IEA) in this table represent 77% of world population, 84% of world GDP, 83% of world electricity generation.
Productivity per Electricity generation (concept similar to Energy intensity) can be measured by dividing GDP amount by the electricity generated. World average was $3.5 production/kWh.
Electricity generation include Final consumption, in process consumption, and losses.
Electricity final consumption by categories (2008)
About 17% of total electricity production is consumed by in-processes, such as self-consumption of power plants, grid losses and storage losses. In 2008, total electricity generation accounted for 20,261 TWh (20.26 PWh), while 3,464 TWh (3.46 PWh) were self-consumption and losses and 16,816 TWh (16.82 PWh) went to final consumption.
In the consumption rate in Industry, China is highest with 67.8%, South Korea is 51.0% (7th), Germany 46.1% (11th), Japan 31.5% (26th), USA 24.0% (28th) In the Commercial and Public Service, Japan is highest with 36.4%, USA 35.6% (3rd), China 5.4% (29th). For Domestic usage, Saudi Arabia is highest with 56.9%, USA 36.2% (8th), Japan 29.8% (16th), China 15.5% (29th), Korea 13.8% (30th).
Definition
Electricity consumption of OECD member countries (2008)
Electric energy consumption per inhabitant by primary energy source in some countries and areas in 2008 is in the table.
1 MW·h/yr = 114 wattFor the OECD with 8 991 kWh/yr/person: 1.026 watt/person.
Electricity scenarios until 2040
In all scenarios, increasing efficiency will result in less electricity needed for a given demand of power and light. But demand will increase strongly on account of
As transport and heating become more climate-friendly, the environmental effect of energy consumption will be more determined by electricity. This is mainly supplied by burning fossil fuel which disturbs the natural carbon cycle. The scenarios arrive at very different results for the environment.
The International Energy Agency expects revision of subsidy for fossil fuel which amounted to 550 billion dollar in 2013, more than four times renewable energy subsidy. In this scenario almost half of the increase in 2040 of electricity consumption is covered by more than 80% growth of renewable energy. Many new nuclear plants will be constructed, mainly to replace old ones. The nuclear part of electricity generation will increase much from 11 to 12%. The renewable part goes up much, from 21 to 33%. The IEA warns that in order to restrict global warming to 2 °C, the carbon dioxide emission must not exceed 1000 gigaton (Gt) from 2014. This limit is reached in 2040 and emissions will not drop to zero ever.
The World Energy Council sees world electricity consumption increasing to more than 40,000 TWh/a in 2040. The fossil part of generation depends on energy policy. It can stay around 70% in the so-called Jazz scenario where countries rather independently "improvise" but it can also decrease to around 40% in the Symphony scenario if countries work "orchestrated" for more climate friendly policy. Carbon dioxide emission, 32 Gt/a in 2012, will increase to 46 Gt/a in Jazz but decrease to 26 Gt/a in Symphony. Accordingly, until 2040 the renewable part of generation will stay at about 20% in Jazz but increase to about 45% in Symphony.