[Tainavi Power Plant Survey] Solar Power Plant Sales Inquiries Up 44.8% Year-on-Year! Record-Breaking Pace! Trend of Used Market Listings Featuring (Individual Owners × Low FIT × Grid Connection 5–8 Years)

Goodfellows Inc. (headquartered in Shinagawa-ku, Tokyo), which operates Tainavi Power Plant—the online marketplace for buying and selling solar power plants and grid-connected battery storage systems—announces the "2026 First-Half Solar Power Plant Sales Market Trends," an analysis of sales inquiry data from January to May 2026.

This latest analysis confirms that not only are sales inquiries increasing, but there is also growing market circulation of power plants with specific characteristics: "low FIT rates," "privately owned," and "connected to the grid 5–8 years ago."

As of the end of May 2026, a total of 533 sales inquiries were recorded—up 44.8% compared to the same period last year (368 inquiries)—marking a sharp increase. If this pace continues, approximately 1,279 inquiries are expected by year-end, surpassing the 2023 annual total of 1,258 inquiries, when large-scale output control measures were widely implemented.

【Main Topics】

◆ Sales inquiries at record-breaking pace! What are the 2026 solar power plant market trends?

◆ What types of power plants are entering the sales market?

◆ Breakdown of sales inquiries by FIT rate and grid connection year

◆ Top 10 prefectures with the most sales inquiries

<Survey Overview>

Survey Target: Sales inquiries on Tainavi Power Plant

Data Period: January 1, 2026 – May 31, 2026

Valid Responses: 533 cases

<Solar Power Plant Sales Market Rapidly Expanding in 2026—Setting New Record Pace>

Analysis of sales inquiry data from Tainavi Power Plant shows a sharp rise in 2026, with 533 cumulative inquiries from January to May—up 44.8% compared to the same period last year (368). The increase was particularly notable in March (+97.7% year-on-year) and April (+116.1% year-on-year). At this current pace, approximately 1,279 inquiries are projected for the full year.

This would exceed the 2023 record high of 1,258 sales inquiries.

<Characteristics of Plants Appearing in the Used Market: Low FIT × Privately Owned × Grid-Connected 5–8 Years Now Dominant>

Detailed Analysis of 2026 Sales Listings

● Ownership Type: Individual owners (72.4% of inquiry submitters)

● FIT Rate: ¥18/kWh or lower (approximately 47% of all listings fall into the low-FIT category)

● Grid Connection Year: Connected between 2018 and 2021 (40% of all plants have been connected for 5–8 years)

● Scale: Primarily low-voltage (single plot with inverter capacity under 50kW)

● Land Type: Land-owning type accounts for approximately 80%

Analysis of 2026 sales inquiries reveals that 72.4% of submitters are individual owners, and about 47% of all listed plants fall into the low-FIT category (selling price of ¥18/kWh or less). These rates are typical for plants certified under the FIT scheme around 2018–2021.

Looking at the distribution by grid connection year, 2020-connected plants are the most common (89 cases), followed by those connected in 2019 and 2021. Overall, 40.3% of listed plants were connected between 2018 and 2021—meaning they have been operational for approximately 5 to 8 years. This indicates a growing market trend of plants sharing the common traits of "5–8 years since grid connection," "low FIT rate," and "privately owned." This period—5 to 8 years into the 20-year FIT revenue window—is considered ideal for transactions, as the plant’s condition can be reliably assessed while a substantial FIT period remains, making it attractive for both sellers and buyers.

Additionally, since the launch of grid-connected battery storage services for low-voltage systems in April 2026, interest among Tainavi Power Plant members has surged. According to member data, interest in grid-connected battery storage systems surpassed interest in solar power plants for the first time in May 2026—suggesting a growing trend of investors considering battery storage as their next investment following the sale of a solar power plant.

<Top 10 Prefectures by Number of Sales Inquiries (January–May 2026)>

Regionally, Ibaraki Prefecture in the Kanto area—known for frequent cable thefts—topped the list with 47 inquiries. Inquiries from Kyushu, where output control volumes are high, remain significant, with Kagoshima Prefecture (2nd place: 42 inquiries) and Miyazaki Prefecture (4th place: 30 inquiries) ranking in the top 10.

◆ About Tainavi Power Plant

"Tainavi Power Plant" is Japan’s largest specialized matching platform for buying and selling solar power plants with land and grid-connected battery storage systems. With over 26,000 members, it offers a wide range of services for power plant investors—not only property transactions but also a site for comparing inverter replacements—and provides nationwide sales support services for plant owners. The platform handles a broad range of services, from valuation to sales brokerage, for power plants ranging from low-voltage to extra-high-voltage systems, managing over 100 sales inquiries per month on average. Since May 2026, it has also begun listing low-voltage grid-connected battery storage systems.

Tainavi Power Plant: https://www.tainavi-pp.com/

◆ About Goodfellows Inc.

Goodfellows Inc. aims to become a leading energy company in Japan, operating businesses in energy media, power source development, product sales, power generation, and M&A support.

Specializing in solar power, battery storage, and renewable energy, the company offers comprehensive services ranging from information provision and equipment installation support to power plant sales and M&A advisory.

Company Name: Goodfellows Inc. Address: DK Gotanda Building 8F, 7-13-5 Nishi-Gotanda, Shinagawa-ku, Tokyo 141-0031 Representative: Yasuhiro Nago, President & CEO Business Activities: Energy media, power development, product sales, power generation, M&A services, etc. URL: https://www.goodfellows.co.jp/

◆ Main Services by Goodfellows Inc.

・Residential solar panel multiple-quote site "Tainavi": https://www.tainavi.com/

・Battery storage multiple-quote site "Tainavi Battery": https://www.tainavi-battery.com/

・Commercial solar panel multiple-quote site "Tainavi NEXT": https://www.tainavi-next.com/

・Solar and grid-connected battery investment property marketplace "Tainavi Power Plant": https://www.tainavi-pp.com/

・Business electricity price comparison site "Switch Biz": https://www.tainavi-biz.com/

・M&A service for energy industry "Tainavi M&A": https://www.tainavi-pp.com/ma/lp/lp01/

・Wholesale sales of renewable energy equipment (solar panels, batteries): https://tainavi-pp.com/procurement/

・Land sales, and development and brokerage of new and used solar power plants

【Copyright and Reproduction Notice】 The copyright of this report belongs to Goodfellows Inc. The findings may be widely used. When reproducing or quoting, please credit "Goodfellows Inc. survey."

※For online media, please credit "Tainavi Power Plant survey" and include a link to "Tainavi Power Plant (https://www.tainavi-pp.com/)."