Company history

In May 1951 the occupation-era Electric Utility Reorganization Order broke up the wartime national generator and its distribution companies, and nine regional utilities were created in a single stroke. Tohoku Electric Power took the assets covering the six Tohoku prefectures plus Niigata — about a fifth of Japan’s land area — with generation, transmission and distribution integrated under one monopoly, headquartered in Sendai and chaired by Shirasu Jiro. It listed in Tokyo that October. The founding condition was awkward: bombed and worn-out plant to repair, and new capacity to build, at the same time.

What made both affordable was the rate structure. Prices were set on full-cost recovery — costs plus a fair return — so capital spending could be pushed into tariffs as demand grew, and the listing added shares and bonds as funding routes. Through the early 1950s the company repaired pre-war hydro and built new stations of several hundred thousand kilowatts at Okutadami and Tagokura, on the Shinano, Mogami and Kitakami rivers.

Hydro alone could not keep up. Korean War demand and the boom that followed pushed consumption up more than 10% a year, and from the Hachinohe thermal unit of June 1958 the company switched to thermal-led development — Sendai from 1960, Niigata from 1963, all coastal, coal- and heavy-oil-fired baseload. Trunk transmission at 154kV and 275kV knitted the seven prefectures into a single operable grid by the mid-1960s, as Sendai, Koriyama and Niigata expanded and industry was recruited into the region.

By 1970 the fleet was oil-heavy — Akita unit 1, the company’s first oil-only station, then Shin-Sendai in 1971 — and in October 1973 crude went from under $3 a barrel to about $12. The fuel bill hit earnings directly, and diversifying away from a single fuel became the central management problem.

The answer took two forms and a long time. Nihonkai LNG was established in August 1978 to import liquefied natural gas through Niigata, with Tohoku Electric holding only 42.3% of the votes alongside the prefecture, a development bank, an oil explorer and a gas utility — which is why the terminal became shared infrastructure supplying city gas feedstock and industrial cold energy rather than one company’s fuel store. First cargo took five years, combined-cycle conversion six, and the second oil crisis intervened, producing a ¥8.5bn recurring loss in the year to March 1980. Then in June 1984 the Onagawa nuclear station, 524MW, began operating on the Pacific coast of Miyagi.

The late 1980s and early 1990s were the heaviest investment years in the company’s history. Onagawa unit 2 at 825MW was built for a 1995 start, and the two 1,000MW Haramachi coal units for 1997 and 1998 — roughly ¥1tn of construction whose depreciation and interest weighed on the 1990s income statement, on the assumption that full-cost recovery would return it through tariffs. With about 25,000 employees and construction flowing to regional contractors through group companies, the utility was among the largest taxpayers and employers in northern Japan. Meanwhile deregulation of electricity had begun appearing on the policy agenda in Europe, America and, by the early 1990s, in Japanese ministry committees.

The Electricity Business Act was amended in April 1995 to open generation to independent producers, ending forty-four years of pure regional monopoly, and in March 2000 retail supply above 2,000kW was liberalised — exposing the paper, chemical and steel plants in Tohoku’s territory to competing suppliers for the first time. The low-fuel-cost Haramachi coal units, commissioned in 1997 and 1998, were the generation answer; the corporate answer was to secure capability and adjacent revenue, taking control of the electrical contractor Yurtec in 2000 and, in 2003–2004, of a geothermal and hydro business bought out of the bankruptcy of Nichijyu and of the group’s telecoms arm. Retail liberalisation was extended to 50kW customers in 2005.

What actually moved the numbers was fuel. Revenue reached ¥1,802.6bn with ¥38.5bn of recurring profit in the year to March 2008, but ROE had already halved to the 5% range, and the following year the company posted a recurring loss of ¥43.1bn — its first — as the financial crisis cut demand while crude peaked at $147. Full-cost recovery allowed fuel costs to be passed through, but with a lag of roughly a year, and the gap fell straight to the bottom line. Profit returned the next year, but the episode showed that a regulated utility is structurally fragile against sudden fuel-price moves.

Kaiwa Makoto became president in June 2010. Eight months later, the ground moved.

The magnitude 9.0 earthquake of 11 March 2011 devastated the network: 4.86 million households lost power within a day. Shin-Sendai and Sendai thermal stations were restored by December, but Haramachi, inside the exclusion zone around Fukushima Daiichi, stayed down until March 2013. All three Onagawa reactors scrammed, and the station survived because its site had been built 13.8m above sea level against a 13m tsunami — but after Fukushima the conditions for restarting any reactor changed entirely. Tohoku Electric bought power, installed emergency generation, and avoided rolling blackouts in the disaster area, which its president treated as the minimum obligation.

The financial damage was structural rather than momentary. Over ¥200bn of extraordinary losses produced the company’s first ever net loss, ¥33.7bn, in the year to March 2011; the year to March 2012 brought a recurring loss of ¥176.5bn and a net loss of ¥231.9bn as replacing nuclear output with thermal generation added roughly ¥150bn of fuel cost. Three years of losses totalled about ¥400bn and equity fell from above 20% of assets to the low teens. An average tariff increase of 8.94% in September 2013 restored profitability by the year to March 2015 — ¥116.6bn recurring, ¥76.5bn net — but that was a price level set to survive without nuclear power, not a recovery of underlying earning capacity.

Full retail liberalisation followed in April 2016, and on 1 April 2020 the company legally separated its grid into Tohoku Electric Power Network, keeping generation and retail in the parent. It was compliance with a statutory deadline rather than a plan of its own, executed with restraint — no new pure holding company, 7,672 employees transferred, the parent’s name and founding year untouched. What the separation revealed was arithmetic: the generation and retail side absorbs fuel and market volatility, posting recurring losses of ¥49.2bn and then ¥199.3bn in the years to March 2022 and 2023 after the invasion of Ukraine, while the grid operates under a revenue cap granting ¥2,394.3bn of allowed revenue over five years from April 2023.

On the generation side the long project finally landed. Onagawa unit 2 restarted in November 2024 — the first restart in eastern Japan since 2011, thirteen years and eight months after the earthquake, following about ¥570bn of safety works over eleven years: a raised seawall, elevated emergency power, filtered venting. Fuel costs fell by tens of billions of yen a year and recurring profit reached ¥256.7bn in the year to March 2025, the best since the disaster. The 2023 group vision sets three pillars — restarting Onagawa 2 and Higashidori 1, developing 2GW of renewables including offshore wind off northern Akita, and new businesses such as attracting data centres. Yurtec was deconsolidated in November 2024, leaving generation-and-retail and the grid as the two poles of the group, and Ishiyama Kazuhiro became president in April 2025.