Data centers and electricity
Data centers consume large amounts of electricity. This page sets out the scale of that demand, the PUE efficiency standard, and new or co-located generation, based on primary sources from the Japanese government and international agencies. Listing information here is not an endorsement or criticism of any position. (All electricity volumes are given in TWh. 1 TWh = 1 billion kWh. Years marked FY are Japanese fiscal years, running April through March.)
Scale of demand — large for a single demand sector
In the Organization for Cross-regional Coordination of Transmission Operators (OCCTO) outlook for FY2050, data center electricity demand is given as a scenario band of Low 43 / Mid 107 / High 211 TWh. Even the High case of 211 TWh is about 20% of Japan's current annual electricity demand (roughly 1,000 TWh), but it is large for a single demand sector: against total current FIT-purchased renewable electricity (about 132 TWh in FY2024, discussed below), the Mid case is about 81% and the High case up to about 1.6 times that volume (a reference comparison between an FY2050 projection and FY2024 actuals, which cover different scopes).
Internationally, the IEA expects electricity consumption by data centers and similar facilities worldwide to reach about 945 TWh in 2030 (roughly double the 2024 level), approaching the scale of Japan's current total electricity consumption (about 1,000 TWh). At the same time, the IEA projects that renewables will cover about half of the growth in global data center demand over the next five years, and that in Japan and South Korea renewables and nuclear together will go from about 35% to nearly 60% of data center consumption — supply is expanding as well.
Growth in supply — FIT solar purchase volume was flat from FY2023 to FY2024
Supply has been expanding too. Renewable electricity purchased under the FIT (feed-in tariff) scheme grew from about 18 TWh in FY2013 to about 132 TWh in FY2024, roughly 7.3 times. Solar, which drove that growth, was essentially flat from FY2023 to FY2024 (about 85 TWh), and the recent overall increase has been carried by wind, biomass and others.
Note: these figures are electricity purchased under the FIT scheme, not total renewable generation (they exclude large hydro, FIP, and self-consumption). On a total-generation basis, solar accounted for about 11.5% of Japan's annual electricity generation in 2024. As noted above, FY2050 data center demand is projected at Mid 107 / High 211 TWh, equivalent to roughly 81% to 1.6 times current FIT-purchased renewable volume (about 132 TWh). That is precisely why efficiency (PUE) matters.
Source: compiled by japandatacenter from 資源エネルギー庁「なっとく！再生可能エネルギー 各種データの公開」C表① (Agency for Natural Resources and Energy, "Nattoku! Renewable Energy — data releases", Table C-1), with unit conversion and fiscal-year aggregation. Used under the Public Data License (PDL1.0).
Efficiency as a yardstick — the PUE standard under the Energy Conservation Act
Because demand is large, how efficiently it is used matters. The revised Act on the Rationalisation of Energy Use and Shift to Non-fossil Energy, in force from July 2026, requires new data centers entering operation from that month to achieve an annual average power usage effectiveness (PUE) of 1.2 or below (to be met permanently within two years of trial operation). Designated operators are also obliged to publish their actual PUE on their own websites. PUE is total facility power divided by IT equipment power: the closer to 1.0, the more efficient, meaning less overhead power for cooling and the like.
Where a facility's PUE has been published, this site shows it on the facility pages together with its position relative to the 1.2 threshold.
New and co-located generation — demand is pulling power development
To meet demand at this scale, utilities are reinforcing the transmission network (the eight major utilities are building or expanding substations at 30 locations nationwide), and there are moves to co-locate or dedicate generation to data centers. Reported cases in Japan include siting on a former power plant site (Satsumasendai), pairing with renewables (Tomakomai), and integrated power plant concepts (JERA). Where operators or local governments have published a relationship with generation, this site records it with sources on the facility pages.
The positional relationship between major transmission lines, substations, and facilities can be viewed on Grid. Physical proximity and available supply capacity are shown separately.
What this site currently covers (reference)
Across facilities published on this site whose power capacity is known, the total is about 1,665 MW (this includes capacity values of different types, so it cannot be compared directly — see Statistics). This is only a small part of all data centers in Japan, and coverage is being expanded continuously.
Sources
- 電力広域的運営推進機関(OCCTO)「2050年度までの全国の長期電力需要想定」(2025年) — OCCTO, nationwide long-term electricity demand projection to FY2050 (2025). Low/Mid/High data center demand scenarios.
- 日本原子力産業協会(IEA「Energy and AI」報告書の紹介) — Japan Atomic Industrial Forum, summarising the IEA report "Energy and AI". Outlook for global data center electricity consumption.
- 資源エネルギー庁「増加が見込まれるデータセンターの電力需要をどうする？」 — Agency for Natural Resources and Energy, on responding to rising data center electricity demand. The PUE 1.2 standard under the Energy Conservation Act.
- 環境省「データセンターにおける再エネ活用促進に係る調査検討」アニュアルレポート — Ministry of the Environment, annual report on promoting renewable energy use at data centers.
- 資源エネルギー庁「なっとく！再生可能エネルギー 各種データの公開」C表①(2025年12月末時点) — Agency for Natural Resources and Energy, "Nattoku! Renewable Energy — data releases", Table C-1 (as of end of December 2025). Trend in FIT-purchased electricity. Compiled by japandatacenter from that Table C-1 with unit conversion and fiscal-year aggregation, used under the Public Data License (PDL1.0).