
The
electric power industry
The electric power industry covers the generation, transmission, distribution and sale of electric power to the general public and industry. The commercial distribution of electric power started in 1882 when electricity was produced for elec ...
in Japan covers the generation, transmission, distribution, and sale of
electric energy
Electrical energy is the energy transferred as electric charges move between points with different electric potential, that is, as they move across a potential difference. As electric potential is lost or gained, work is done changing the energy o ...
in
Japan
Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...
. Japan consumed approximately 918 terawatt-hours (TWh) of electricity in 2014.
Before the 2011
Fukushima Daiichi nuclear disaster
The Fukushima nuclear accident was a major nuclear accident at the Fukushima Daiichi Nuclear Power Plant in Ōkuma, Fukushima, Japan, which began on 11 March 2011. The cause of the accident was the 2011 Tōhoku earthquake and tsunami, which r ...
, about a quarter of electricity in the country was generated by nuclear power.
In the following years, most nuclear power plants have been on hold, being replaced mostly by coal and natural gas. Solar power is a growing source of electricity, and Japan has the third largest solar installed capacity with about 50 GW as of 2017. Japan's electricity production is characterized by a diverse energy mix, including nuclear, fossil fuels, renewable energy, and hydroelectric power. Japan has the second largest
pumped-hydro storage installed capacity in the world after China.
The electrical grid in Japan is isolated, with no international connections, and consists of four
wide area synchronous grids. Unusually, the Eastern and Western grids run at different frequencies (50 and 60 Hz respectively) and are connected by
HVDC
A high-voltage direct current (HVDC) electric power transmission system uses direct current (DC) for electric power transmission, in contrast with the more common alternating current (AC) transmission systems. Most HVDC links use voltages betwe ...
connections. This considerably limits the amount of electricity that can be transmitted between the north and south of the country.
During the
Second Sino-Japanese War
The Second Sino-Japanese War was fought between the Republic of China (1912–1949), Republic of China and the Empire of Japan between 1937 and 1945, following a period of war localized to Manchuria that started in 1931. It is considered part ...
and the succeeding
Pacific War
The Pacific War, sometimes called the Asia–Pacific War or the Pacific Theatre, was the Theater (warfare), theatre of World War II fought between the Empire of Japan and the Allies of World War II, Allies in East Asia, East and Southeast As ...
, the entirety of Japan's electricity sector was state-owned; the system at the time consisted of a and several electricity distributors. At the behest of the
Supreme Commander for the Allied Powers
The Supreme Commander for the Allied Powers (), or SCAP, was the title held by General Douglas MacArthur during the United States-led Allied occupation of Japan following World War II. It issued SCAP Directives (alias SCAPIN, SCAP Index Number) ...
, Nippon Hassōden became the
Electric Power Development Co., Limited in the fifties; and almost all of the electricity sector that are not under the control by EPDC was privatized into nine
government-granted monopolies. The
Ryukyu Islands
The , also known as the or the , are a chain of Japanese islands that stretch southwest from Kyushu to Geography of Taiwan, Taiwan: the Ryukyu Islands are divided into the Satsunan Islands (Ōsumi Islands, Ōsumi, Tokara Islands, Tokara and A ...
electricity provider was, during the
USCAR era, publicly owned; it was privatized shortly after
the islands' admission into Japan.
Consumption
In 2008, Japan consumed an average of 8507
kWh/person of electricity. That was 115% of the
EU15 average of 7409 kWh/person and 95% of the
OECD
The Organisation for Economic Co-operation and Development (OECD; , OCDE) is an international organization, intergovernmental organization with 38 member countries, founded in 1961 to stimulate economic progress and international trade, wor ...
average of 8991 kWh/person.
[Energy in Sweden, Facts and figures, The Swedish Energy Agency, (in Swedish: Energiläget i siffror), Table: Specific electricity production per inhabitant with breakdown by power source (kWh/person), Source: IEA/OEC]
2006 T23
2007 T25
2008 T26
2009 T25
an
2010 T49
.
Compared with other nations, electricity in Japan is relatively expensive.
Liberalization of the electricity market
Since the
Fukushima Daiichi nuclear disaster
The Fukushima nuclear accident was a major nuclear accident at the Fukushima Daiichi Nuclear Power Plant in Ōkuma, Fukushima, Japan, which began on 11 March 2011. The cause of the accident was the 2011 Tōhoku earthquake and tsunami, which r ...
, and the subsequent large scale shutdown on the
nuclear power industry
Nuclear power is the use of nuclear reactions to produce electricity. Nuclear power can be obtained from nuclear fission, nuclear decay and nuclear fusion reactions. Presently, the vast majority of electricity from nuclear power is produced by ...
, Japan's ten regional electricity operators have been making very large financial losses, larger than US$15 billion in both 2012 and 2013.
Since then steps have been made to
liberalize the electricity supply market.
In April 2016 domestic and small business mains voltage customers became able to select from over 250
supplier companies competitively selling electricity, but many of them sell only locally, mainly in large cities. Also wholesale electricity trading on the
Japan Electric Power Exchange (JEPX), which previously traded only 1.5% of power generation, was encouraged.
By June 2016 more than 1 million consumers had changed supplier.
However total costs of liberalization to that point were around
¥80 billion, so it is unclear if consumers had benefited financially.
In 2020 transmission and distribution infrastructure access will be made more open, which will help competitive suppliers cut costs.
Transmission

Electricity transmission in Japan is unusual because the country is divided for historical reasons into two regions each running at a different
mains frequency.
Eastern Japan has 50 Hz networks while western Japan has 60 Hz networks.
Limitations of conversion capacity causes a bottleneck to transfer electricity and shift imbalances between the networks.
Eastern Japan (consisting of
Hokkaido
is the list of islands of Japan by area, second-largest island of Japan and comprises the largest and northernmost prefectures of Japan, prefecture, making up its own list of regions of Japan, region. The Tsugaru Strait separates Hokkaidō fr ...
,
Tohoku,
Kanto, and eastern parts of
Chubu) runs at 50 Hz; Western Japan (including most of Chubu,
Kansai
The or the lies in the southern-central region of Japan's main island Honshū. The region includes the prefectures of Nara, Wakayama, Kyoto, Osaka, Hyōgo and Shiga, often also Mie, sometimes Fukui, Tokushima and Tottori. The metropoli ...
,
Chugoku,
Shikoku
is the smallest of the List of islands of Japan#Main islands, four main islands of Japan. It is long and between at its widest. It has a population of 3.8 million, the least populated of Japan's four main islands. It is south of Honshu ...
, and
Kyushu
is the third-largest island of Japan's Japanese archipelago, four main islands and the most southerly of the four largest islands (i.e. excluding Okinawa Island, Okinawa and the other Ryukyu Islands, Ryukyu (''Nansei'') Ryukyu Islands, Islands ...
) runs at 60 Hz.
That originates from the first purchases of generators from
AEG The initials AEG are used for or may refer to:
Common meanings
* AEG (German company)
; AEG) was a German producer of electrical equipment. It was established in 1883 by Emil Rathenau as the ''Deutsche Edison-Gesellschaft für angewandte El ...
for Tokyo in 1895 and from
General Electric
General Electric Company (GE) was an American Multinational corporation, multinational Conglomerate (company), conglomerate founded in 1892, incorporated in the New York (state), state of New York and headquartered in Boston.
Over the year ...
for Osaka in 1896.
The frequency difference partitions Japan's national grid and so power can be moved only between the two parts of the grid using
frequency converters, or
HVDC
A high-voltage direct current (HVDC) electric power transmission system uses direct current (DC) for electric power transmission, in contrast with the more common alternating current (AC) transmission systems. Most HVDC links use voltages betwe ...
transmission lines. The boundary between the two regions has four back-to-back
HVDC
A high-voltage direct current (HVDC) electric power transmission system uses direct current (DC) for electric power transmission, in contrast with the more common alternating current (AC) transmission systems. Most HVDC links use voltages betwe ...
substations, which convert the frequency:
Shin Shinano,
Sakuma Dam,
Minami-Fukumitsu, and the
Higashi-Shimizu Frequency Converter. The total transmission capacity between the two grids is 1.2 GW.
The limitations of these links have been a major problem in providing power to the areas of Japan affected by the
Fukushima Daiichi nuclear disaster
The Fukushima nuclear accident was a major nuclear accident at the Fukushima Daiichi Nuclear Power Plant in Ōkuma, Fukushima, Japan, which began on 11 March 2011. The cause of the accident was the 2011 Tōhoku earthquake and tsunami, which r ...
.
During the
2011 Tōhoku earthquake and tsunami
On 11 March 2011, at 14:46:24 Japan Standard Time, JST (05:46:24 UTC), a 9.0–9.1 Submarine earthquake, undersea megathrust earthquake occurred in the Pacific Ocean, east of the Oshika Peninsula of the Tōhoku region. It lasted approx ...
, there were blackouts in some areas of the country because of the insufficient ability of the three
HVDC converter stations to transfer energy between both networks.
A few projects are underway to increase the electricity transfer between the 50 Hz (eastern Japan) and 60 Hz networks (western Japan) which will improve power reliability in Japan.
In April 2019, Hitachi ABB HVDC Technologies secured an HVDC order for the Higashi Shimizu project to increase the interconnection capacity between the 60Hz area of Chubu Electric and the 50Hz area of
TEPCO from 1.2GW to 3GW.
Chubu Electric will increase the interconnection capacity of the Higashi Shimizu Substation from 300MW to 900MW which should be operational by 2027.
OCCTO (Organization for Cross-regional Coordination of Transmission Operators) supervises the power interchange among electric power companies.
Mode of production
According to the
International Energy Agency
The International Energy Agency (IEA) is a Paris-based autonomous intergovernmental organization, established in 1974, that provides policy recommendations, analysis and data on the global energy sector. The 31 member countries and 13 associatio ...
, Japanese gross production of electricity was 1,041 TWh in 2009, making it the world's third largest producer of electricity with 5.2% of the
world's electricity.
[IEA Key World Energy Statistic]
2011
2010
2009
2006
IEA October, pages electricity 27 gas 13,25 fossil 25 nuclear 17 After Fukushima, Japan imported an additional 10 million short tons of coal and
liquefied natural gas
Liquefied natural gas (LNG) is natural gas (predominantly methane, CH4, with some mixture of ethane, C2H6) that has been cooled to liquid form for ease and safety of non-pressurized storage or transport. It takes up about 1/600th the volume o ...
imports rose 24% between 2010 and 2012. In 2012 Japan used most of its natural gas (64%) in the power sector.
Nuclear power
Nuclear power
Nuclear power is the use of nuclear reactions to produce electricity. Nuclear power can be obtained from nuclear fission, nuclear decay and nuclear fusion reactions. Presently, the vast majority of electricity from nuclear power is produced by ...
was a national strategic priority in
Japan
Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...
. Following the 2011
Fukushima nuclear accidents, the national nuclear strategy is in doubt due to increasing public opposition to nuclear power. An energy white paper, approved by the
Japanese Cabinet in October 2011, reported that "public confidence in safety of nuclear power was greatly damaged" by the Fukushima disaster, and it calls for a reduction in the nation's reliance on nuclear power.
Following the 2011 accident, many reactors were shut down for inspection and for upgrades to more stringent safety standards. By October 2011, only 11 nuclear power plants were operating in Japan, and all 50 nuclear reactors were offline by 15 September 2013. That left Japan without nuclear energy for only the second time in almost 50 years. Carbon dioxide emissions from the electricity industry rose in 2012, reaching levels 39% more than when the reactors were in operation.
Sendai 1 reactor was restarted on 11 August 2015, the first reactor to meet new safety standards and be restarted after the shutdown. As of July 2018, there are nine reactors that have been restarted.
Hydro power
Hydroelectricity is Japan's main renewable energy source, with an installed capacity of about 27 GW, or 16% of the total generation capacity, of which about half is
pumped-storage. The production was 73 TWh in 2010.
As of September 2011, Japan had 1,198 small hydropower plants with a total capacity of 3,225 MW. The smaller plants accounted for 6.6 percent of Japan's total hydropower capacity. The remaining capacity was filled by large and medium hydropower stations, typically sited at large dams.
Other renewables
Benjamin K. Sovacool estimated that Japan has a total of "324 GW of achievable potential in the form of onshore and offshore
wind turbine
A wind turbine is a device that wind power, converts the kinetic energy of wind into electrical energy. , hundreds of thousands of list of most powerful wind turbines, large turbines, in installations known as wind farms, were generating over ...
s (222 GW),
geothermal power
Geothermal power is electricity generation, electrical power generated from geothermal energy. Technologies in use include dry steam power stations, flash steam power stations and binary cycle power stations. Geothermal electricity generation i ...
plants (70 GW), additional hydroelectric capacity (26.5 GW), solar energy (4.8 GW) and agricultural residue (1.1 GW)."
[Benjamin K. Sovacool , 2011, . '' Contesting the Future of Nuclear Power: A Critical Global Assessment of Atomic Energy'', ]World Scientific
World Scientific Publishing is an academic publisher of scientific, technical, and medical books and journals headquartered in Singapore. The company was founded in 1981. It publishes about 600 books annually, with more than 170 journals in var ...
, p. 287.
One result of the Fukushima Daiichi nuclear disaster could be renewed public support for the
commercialization of renewable energy technologies. The Japanese government announced in May 2011 a goal of producing 20% of the nation's electricity from renewable sources, including solar, wind, and biomass, by the early 2020s. In August 2011, the Japanese Government passed a bill to subsidize electricity from renewable energy sources. The legislation will become effective on 1 July 2012, and require utilities to buy electricity generated by renewable sources including
solar power
Solar power, also known as solar electricity, is the conversion of energy from sunlight into electricity, either directly using photovoltaics (PV) or indirectly using concentrated solar power. Solar panels use the photovoltaic effect to c ...
,
wind power
Wind power is the use of wind energy to generate useful work. Historically, wind power was used by sails, windmills and windpumps, but today it is mostly used to generate electricity. This article deals only with wind power for electricity ge ...
and
geothermal energy
Geothermal energy is thermal energy extracted from the crust (geology), crust. It combines energy from the formation of the planet and from radioactive decay. Geothermal energy has been exploited as a source of heat and/or electric power for m ...
at above-market rates.
In 2011 Japan planned to build as many as 80 floating wind turbines off Fukushima by 2020.
In 2020, seven years after the world's first pilot floating wind turbine was installed off Fukushima in 2013, the Japanese government announced its withdrawal from the offshore wind farm.
[Failure seven years after the world's first floating wind turbine]
Power stations
Grid storage
Japan relies mostly on pumped storage hydroelectricity to balance demand and supply. As of 2014, Japan has the largest pumped storage capacity in the world, with over 27 GW.
See also
*
Japan Electric Association The (JEA) is a membership organisation for the electricity sector in Japan and, although it has roots dating back to 1892, was founded in October 1921.
*
Energy in Japan
References
{{Asia topic, Electricity sector in
ja:日本の電力会社