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Share and Deployment Status of Renewable Electricity in Japan in FY2024 (Preliminary Report)

Japan’s renewable electricity share edged up to 26.5 percent in FY2024, but variable renewables remain dominated by solar power and the country still needs a substantial acceleration to meet its 2030 target.

国内の2024年度の自然エネルギー電力の割合と導入状況(速報)

Institute for Sustainable Energy Policies · By Institute for Sustainable Energy Policies · 31 October 2025 · read the original in Japanese →

Share and Deployment Status of Renewable Electricity in Japan in FY2024 (Preliminary Report), October 31, 2025. Share and Deployment Status of Renewable Electricity in Japan in FY2024 (Preliminary Report): The share of renewable electricity rises slightly to 26.5%, with VRE entering the 12% range. Institute for Sustainable Energy Policies, a specified nonprofit corporation, October 31, 2025.

In order to assess the extent to which renewable energy has been introduced in Japan, this preliminary report presents the latest data through the end of FY2024 on such matters as the share of renewables in annual electricity generation, the capacity of renewable power generation facilities installed under the FIT system, and shares by electricity supply-and-demand area.

Summary: Share of renewable electricity in FY2024.要旨 2024年度の自然エネルギー電力の割合

An estimate of the share of annual electricity generation in Japan supplied by renewables in FY2024 shows a rise of about 0.4 percentage points from the previous fiscal year, to 26.5% (Figure 1). This corresponds to roughly 70% of the target set for FY2030 in the Sixth Strategic Energy Plan (36-38%), but an increase of around another 11 percentage points in renewables is still required. Until FY2012, the share of annual electricity generation from renewables in Japan hovered at around 10%; by FY2024, however, annual renewable electricity generation had increased to roughly 2.4 times its FY2012 level, owing in particular to the deployment of renewable power generation facilities under the FIT system. The renewable energy source that increased the most was solar power, which reached 11.5% of Japan’s annual electricity generation. Although this was only about 0.2 percentage points higher than the previous fiscal year’s 11.3%, it was roughly 15 times the FY2012 level. Biomass generation, too, is nearly five times its FY2012 level, and its share has reached 6.0%. Wind power, by contrast, remains low at 1.2%, though it has more than doubled compared with FY2012. Geothermal remains at 0.3%, about 1.3 times its FY2012 level. The share of variable renewable energy (VRE), combining solar and wind, was about 12.6%; yet wind power in Japan has only just entered the 1% range, and its annual generation remains at roughly one-tenth that of solar power. Looking at renewable generation in FY2024 by month, the share was highest in May 2024, reaching 34.7%, with hydropower at 11.2% and solar at 15.8%. The share of variable renewable energy (VRE) was likewise highest in May 2023, reaching 16.5% (Figure 2).

The share of renewables in annual electricity generation in Japan is estimated by compiling sources such as the Electric Power Survey Statistics published by the Agency for Natural Resources and Energy. These statistics aggregate data, mainly for generation facilities with output of 1 MW or more, from electric power businesses across the country (about 1,660 companies in FY2024), and also survey such items as electricity received from other businesses and electricity generated for self-consumption through in-house generation [1]. However, because the method used to compile these statistics was substantially revised from FY2016 onward as a result of electricity market liberalization, the contents of the data require a certain degree of scrutiny. At present, some inconsistencies are thought to exist in the wind-power data, so estimates were made from electricity supply-and-demand data (hourly data) published each month by general transmission and distribution operators. For solar power as well, FY2024 data are available from the Electric Power Survey Statistics, the electricity supply-and-demand data of general transmission and distribution operators, and FIT purchase volumes; and even compared with the FY2023 Comprehensive Energy Statistics, there is variation of around 10% in annual generation. In order to compare with past data, however, the Electric Power Survey Statistics data are used here (Figure 3). As a result, the estimate of annual solar power generation may contain an upward error of as much as about 20%. Since the Electric Power Survey Statistics do not compile data on self-consumption from residential solar power, this portion is estimated from electricity transmitted under the FIT system, assuming a self-consumption rate of 30%.

Nuclear power, from zero annual generation in FY2014, has risen as reactors have been restarted in Kyushu, Kansai, and Shikoku, reaching 8.8% in FY2024. As a result, annual generation from nuclear power is about 30% of that from renewables.

As shown in Figure 4, fossil fuels still account for a large share of Japan’s power mix, reaching 64.6% in FY2024, or about two-thirds of total annual electricity generation; nevertheless, this share has fallen by more than 20 percentage points from its peak in FY2022 (88%). In the FY2024 breakdown, natural gas (LNG) has the largest share at 29.1%, but is flat compared with the previous fiscal year. Coal also accounts for 28.3%, almost unchanged from the previous fiscal year (Table 1). Although there is a policy of phasing out inefficient coal-fired generation facilities, high-efficiency coal-fired power plants will remain beyond FY2030 if decarbonization measures are taken; if such measures do not advance, there is concern that they will be locked in over the long term. As an energy policy consistent with the Paris Agreement, the challenge is how quickly all coal-fired power can be phased out toward 2030, as in European countries.

Figure 1: Trends in the share of electricity generation from renewables and nuclear power in Japan. Source: Prepared by ISEP from the Agency for Natural Resources and Energy’s Electric Power Survey Statistics and other sources.

Figure 2: Monthly share of renewables in total electricity generation in Japan (FY2024). Source: Prepared by ISEP from Electric Power Survey Statistics and other sources. Figure 3: Comparison of annual solar power generation in Japan by statistical dataset. Source: Prepared by ISEP from each statistical dataset. Figure 4: Japan’s power mix (annual generation in FY2024). Source: Prepared by ISEP from the Agency for Natural Resources and Energy’s Electric Power Survey Statistics and other sources. Table 1: Changes in Japan’s power mix. Source: Prepared by ISEP from the Agency for Natural Resources and Energy’s Electric Power Survey Statistics and other sources.

Figure 5 shows the transition in Japan’s power mix from the 1990s onward. Total electricity generation has declined by about 20% from its peak year (2007), and in FY2023 also decreased from the previous fiscal year. Annual renewable electricity generation had remained at 10% of total generation until FY2010, but had more than doubled to 26% by FY2024. Since March 11, nuclear power generation has fallen sharply, from more than 25% before March 11 to about 9%, or roughly one-third of its former level. The share of thermal power generation from fossil fuels rose to about 90% after March 11, but has since fallen to around 65%.

Figure 5: Changes in Japan’s power mix (annual electricity generation). Source: Prepared by ISEP from Electric Power Survey Statistics data and other sources.図5: 日本国内の電源構成(年間発電電力量)の推移出所: 電力調査統計データなどからISEP作成

Figure 6 shows cumulative installed capacity of renewable power generation facilities in Japan, excluding large-scale hydropower. In the 1990s, large-scale hydropower was the main renewable energy source in Japan, and installed capacity of other renewables was very small, at about 5 million kW. In the 2000s, deployment of some forms of “new energy” advanced under the RPS system from 2003, and in 2009 the FIT system for surplus solar electricity began; by FY2011, renewable power generation facilities other than large-scale hydropower had also grown roughly threefold, to about 15 million kW. Under the FIT system, which began in 2021 and covered all quantities and all categories, solar power capacity increased by about ten times over the twelve years from FY2012 to FY2024, reaching 73 million kW on an AC basis, and renewable power generation facilities excluding large-scale hydropower reached about 93 million kW. Within this total, cumulative installed capacity of wind power was 6.2 million kW, almost all of it onshore wind. This was about 2.4 times the level of eleven years earlier, in FY2012, but still only one-twelfth of solar power capacity. Cumulative installed biomass power capacity was about 8.5 million kW, having increased by about 2.5 times over these eleven years as facilities using woody biomass as fuel grew. For geothermal power and small hydropower, new deployment of small-scale facilities advanced, but there were also many replacements; cumulative installed capacity has scarcely increased, standing at about 600,000 kW for geothermal power and about 4.5 million kW for small hydropower.

Figure 6: Changes in cumulative installed capacity of renewable power generation facilities in Japan, excluding large-scale hydropower. Source: Prepared by ISEP from Agency for Natural Resources and Energy data and other sources. Deployment status of renewables under the FIT system.

Capacity certified for projects under the FIT system, which began in July 2012, reached 111.1 million kW by the end of FY2023, including transitional certifications from before the system began; of this, 72%, or 79.5 million kW, was solar power (Figure 7, Table 2) [2]. Facilities that had actually begun operation totaled 87.4 million kW, leaving 23.44 million kW not yet in operation. The operation commencement rate for commercial solar power (10 kW or more) has reached about 90%. For wind power (20 kW or more), about 16.3 million kW has been certified for projects, including transitional certifications, but because of environmental assessment procedures and grid-connection procedures, only about 6 million kW, or roughly 31%, has begun operation. In electricity areas with high shares of variable renewable energy (VRE), such as solar power, curtailment of VRE output has been implemented since FY2022 (and since FY2018 in the Kyushu area) [3]. For small and medium hydropower, project certification remains at about 2.75 million kW, of which 1.54 million kW has begun operation, though a considerable share consists of replacement of existing facilities. Geothermal power remains low, with 220,000 kW certified for projects, but about 140,000 kW has begun operation, showing that development is advancing. About 9.65 million kW of biomass power has been certified for projects, but more than 70% is said to consist of facilities fueled by imported wood and agricultural residues such as PKS and palm oil. Biomass power facilities that have begun operation total 6.5 million kW, exceeding the capacity of wind power, and the operation commencement rate has risen to 67%. With respect to biomass fuels imported from overseas, the sustainability of liquid biomass in particular, such as palm oil, has been viewed as a problem, and work is proceeding to establish sustainability criteria [4].

Figure 7: Project certification, installed capacity (operation commenced), and non-operating facilities under the FIT system (end of FY2023). Source: Prepared by ISEP from Agency for Natural Resources and Energy data.

Table 2: Project certification, installed and non-operating facilities under the FIT system (end of FY2023), including transitional certifications. Source: Prepared from Agency for Natural Resources and Energy data.

Figure 8 shows changes in cumulative installed capacity of renewable power generation facilities under the FIT system. Facility certification had advanced to nearly 120 million kW by FY2016, and non-operating facilities increased; but from FY2017 onward, with revisions to the FIT system including transition to project certification, the operation commencement rate had reached about 76% by the end of FY2022. For solar power in particular, the operation commencement rate has reached nearly 90%.

Figure 8: Changes in cumulative installed capacity of renewable power generation facilities under the FIT system, certified projects, and non-operating facilities. Source: Prepared by ISEP from Agency for Natural Resources and Energy data.

Looking at annual installations under the FIT system by fiscal year, FY2014 was the largest, reaching nearly 10 million kW, centered on solar power; thereafter the figure turned downward, and from FY2017 annual installations were around 6 million to 7 million kW, before declining to about 5 million kW in FY2023 (Figure 9). For solar power, annual installations exceeded 5 million kW through FY2020, but new purchase prices also fell rapidly, an auction system was introduced for large-scale projects, and the FIP system began in FY2022; as a result, installations fell to the 4 million kW range from FY2021 and to 3 million kW in FY2023. Wind power, whose deployment had been constrained until now, has shown a tendency toward increased annual installations. Wind power had previously remained at about 500,000 kW or less, but in FY2022 more than 1 million kW was newly installed in a single year. Biomass power has also seen installations of more than 400,000 kW since FY2017, with the largest annual addition, 1.31 million kW, in FY2022, but in FY2023 it remained at about 600,000 kW. Geothermal power saw about 40,000 kW installed in FY2023, the second-largest scale after about 50,000 kW in FY2019.

Figure 9: Changes in annual installations of renewable power generation facilities under the FIT system. Source: Prepared by ISEP from Agency for Natural Resources and Energy data.図9: FIT制度による自然エネルギー発電設備の年間導入量の推移出所：資源エネルギー庁データよりISEP作成

The total amount paid for purchases under the FIT system is expected to rise slightly in FY2024 to 4.8 trillion yen, from 4.7 trillion yen in FY2023, but avoided costs, corresponding to the reduction in fossil fuels for electric power companies, are expected to fall sharply to about 2.1 trillion yen from the previous fiscal year’s 3.6 trillion yen, owing to factors such as the surge in fossil fuel prices. As a result, the surcharge on electricity rates in FY2024 rose sharply from the previous fiscal year’s 1.4 yen/kWh, reaching 3.49 yen/kWh, about the same as in FY2022 (Figure 10). Amid this, a fundamental review of the current FIT system began in FY2022. The system changed substantially: FIT is maintained, with conditions, for locally utilized power sources such as small-scale solar including solar sharing, small hydropower, small biomass, and small geothermal, while a new FIP system has been introduced for competitive power sources such as large-scale solar and wind [5]. However, this review of the FIT system contains various problems, and proposals have been made to promote the deployment of renewable energy in earnest [6].

Figure 10: Changes in purchase costs, surcharges, and other items under the FIT system. Source: Prepared by ISEP from Agency for Natural Resources and Energy data. Share of renewables in Japan’s electricity supply and demand.

Based on electricity supply-and-demand data published monthly by the ten general transmission and distribution operators for each area nationwide, data for the full year of FY2023 were compiled, focusing on the share of renewables in grid electricity demand and related indicators. For Japan’s electricity supply-and-demand data, ISEP’s Energy Chart makes it possible to analyze published data interactively and accessibly through a variety of graphs [7].

The share of renewables in annual electricity demand for Japan as a whole averaged 22.6% in FY2023, up from the FY2022 annual average of 21.4% (Figure 11). In the breakdown, solar power accounted for 10.7%; combined with wind power’s 1.2%, the share of variable renewable energy, or VRE, was 11.9%. Solar increased from 10.0% in FY2023, and its share is now larger than hydropower’s 8.0%. Biomass power increased from 2.1% in the previous fiscal year to 2.4%. The nuclear power share in FY2023, meanwhile, was 9.3%, up from 6.2% the year before. In monthly averages for the share of renewables in electricity demand for Japan as a whole, May 2023 was the highest at 32.5%, up from 30.3% the previous year. At that time, the share of VRE, or variable renewable energy, was also at its maximum, 16.5%, up from 15.4% in April of the previous year. Its components were solar power at 15.4% and wind power at 1.1%.

Figure 11: Monthly shares of renewables and nuclear power in electricity supply and demand nationwide in Japan (FY2024). Source: Prepared from electricity supply-and-demand data of general transmission and distribution operators.

In FY2023, the areas with the highest annual average shares of renewables in electricity demand were the Hokkaido and Tohoku areas, both at 41.1%; in each area, hydropower accounted for a relatively large share, at 15.6% and 14.6%, respectively, while solar power also reached 10.4% and 13.6% (Figure 12, Table 3). Their wind power shares, at 8.0% and 5.8%, were among the highest nationwide, and their VRE shares were 18.4% and 19.4%, respectively. Biomass power shares were also high nationwide, at 6.7% and 5.5%, respectively, and geothermal power accounted for 0.3% and 1.5%. The Hokuriku area ranked third, with a renewable energy share of 35.8%, but hydropower accounted for a large 26.8%, while VRE had a low share of 6.7%.

In FY2023, there were five areas where the share of renewables exceeded 100% of demand at the peak hourly value: the Shikoku area, with a maximum of 123%, as well as the Tohoku area (117%), the Hokkaido area (111%), and the Hokuriku area (100%). In areas such as Kyushu, where the share had previously exceeded 100%, the maximum at peak times was below 100% because of the effects of output curtailment.

In the Kyushu area, where VRE output curtailment has already been implemented since 2018, the VRE curtailment rate has reached 8.4%; in FY2023, VRE output curtailment was implemented in eight areas other than Tokyo Electric Power (the national average was 1.8%). The curtailment rate in the Chugoku area was 3.6%, the second highest after Kyushu; in the five areas other than Shikoku, at 1.8%, it was below 1%. In the Shikoku area, where the solar share is 16.7%, the highest nationwide, the renewable energy share was 35.0%; the VRE share, combined with wind’s 2.0%, was 18.7%, the highest in the country. In the Kyushu area, by contrast, the curtailment rate in FY2023 was the highest nationwide, and the post-curtailment VRE share was 16.7%, while the pre-curtailment VRE share was 18.2%. In Kyushu, the share of nuclear power, which under priority dispatch rules is treated as baseload power and is not curtailed until the end, has also risen with reactor restarts; at times four nuclear reactors, with a combined output of about 4 million kW, were in operation, and the FY2023 share reached 37.4%. On the Kyushu mainland, following the increase in solar power after October 2018, full-scale curtailment of solar and wind output has been carried out intermittently; over the year of FY2023, the curtailment rate more than doubled from the previous fiscal year’s 3.0% to 8.4%, the highest ever recorded.

Figure 12: Share of renewables in electricity supply and demand by area (FY2024). Source: Prepared from electricity supply-and-demand data of general transmission and distribution operators. Table 3: Share of renewables in demand by electricity supply-and-demand area. Source: Prepared from electricity supply-and-demand data of general transmission and distribution operators.

In FY2023, there were six areas where renewables exceeded 100% of electricity demand on an hourly basis: Hokkaido, Tohoku, Hokuriku, Chubu, Shikoku, and Chugoku (line graph in Figure 12). In the previous fiscal year, FY2022, there had been seven areas including Kyushu, but in the Kyushu area the share did not exceed 100% in 2023 as the curtailment rate increased (the maximum was 92.9%). In the Shikoku area, meanwhile, the share of renewables in electricity demand reached 123.1% during the 10 a.m. hour on May 3, 2023. At this peak, solar accounted for 91.7% and wind for 1.4%, making the VRE share 93.1% (the maximum for solar was 93.2%). Together with hydropower at 26.4% and biomass at 3.7%, the total reached 123.1%. Even in metropolitan areas, in the Chubu area where output control has begun, the renewable energy share reached a maximum of 109.2% (solar’s maximum was 92%). In the Kyushu area, where output curtailment is being implemented, the hourly share of solar power reached a maximum of 83.2% at its peak. At that time wind was 0.1%, so the VRE share remained at 83.3%, and output curtailment was not implemented. In the Kyushu area, however, the pre-curtailment VRE share reached a maximum of 132.5% during the noon hour on April 9, 2023. At that time, VRE output curtailment reduced the VRE share to 53.1% (a curtailment rate of 60%).

Figure 13: VRE output curtailment rates by electricity area (FY2024). Source: Prepared from electricity supply-and-demand data of general transmission and distribution operators. Reference materials.図13 電力エリア別のVRE出力抑制率(2024年度) 出所：一般送配電事業社の電力需給データより作成参考資料

[1] Agency for Natural Resources and Energy, “Electric Power Survey Statistics,” http://www.enecho.meti.go.jp/statistics/electric_power/ep002/

[2] Agency for Natural Resources and Energy, “Website for Public Disclosure of Information under the Act on Special Measures Concerning Promotion of Utilization of Electricity from Renewable Energy Sources,” https://www.fit-portal.go.jp/PublicInfoSummary

[3] ISEP, “Curtailment of Solar and Wind Output by Tohoku, Shikoku, and Chugoku Electric Power Could Have Been Sufficiently Avoided” (May 2022), https://www.isep.or.jp/archives/library/13912

[4] “Joint Proposal on the Sustainability of Biomass Power Generation” (July 2019), https://www.isep.or.jp/archives/library/12006

[5] “Bill to Partially Amend the Electricity Business Act and Other Acts to Establish a Resilient and Sustainable Electricity Supply System” (February 2020), https://www.meti.go.jp/press/2019/02/20200225001/20200225001.html

[6] ISEP, “A ‘Green Recovery’ from the Regions: Overcoming the Three Crises Caused by COVID-19 (Economic Crisis, Climate Crisis, and Social Division)” (July 2020), https://www.isep.or.jp/archives/library/12694

Share and Deployment Status of Renewable Electricity in Japan in FY2024 (Preliminary Report)

Summary: Share of renewable electricity in FY2024.要旨 2024年度の自然エネルギー電力の割合

Figure 5: Changes in Japan’s power mix (annual electricity generation). Source: Prepared by ISEP from Electric Power Survey Statistics data and other sources.図5: 日本国内の電源構成(年間発電電力量)の推移 出所: 電力調査統計データなどからISEP作成

[7] ISEP Energy Chart, http://www.isep.or.jp/chart/[7] ISEP Energy Chart http://www.isep.or.jp/chart/

Figure 5: Changes in Japan’s power mix (annual electricity generation). Source: Prepared by ISEP from Electric Power Survey Statistics data and other sources.図5: 日本国内の電源構成(年間発電電力量)の推移出所: 電力調査統計データなどからISEP作成