The Tokyo Metropolitan Government is promoting a program that provides focused support to owners of rental housing who undertake insulation renovations and other measures that contribute to tenant health, soundproofing, and crime prevention. The government also provides financial assistance for the costs associated with introducing renewable energy through a combination of solar power generation and low-voltage bulk power supply.
We are pleased to announce that we are now accepting advance applications for grants and business registrations under the Intensive Promotion Program for Insulation and Renewable Energy in Rental Housing (FY2026 budget: 21.8 billion yen).

1. Business Overview

(1) Energy Efficiency (Existing Homes)

We provide grants to owners of single-building rental properties who conduct energy efficiency assessments and display the results, and who carry out renovations to ensure thermal insulation performance meets or exceeds a certain standard.

Eligibility for Grants	Grant Rate	Upper limit	Requirements
Highly insulated windows	two-thirds	300,000 yen per unit	The product must be registered as eligible for subsidies under the National Subsidy Program for Carbon Dioxide Emission Reduction Measures, the Advanced Window Renovation Program, or the Future Eco-Housing Program, etc.
Highly Insulated Door	two-thirds	270,000 yen per unit	・The product must be registered as eligible for subsidies under the Advanced Window Renovation Program or the Future Eco-Housing Program. ・The product must be installed in conjunction with window or insulation renovations, etc.
Insulation retrofitting for walls, floors, etc.	two-thirds	600,000 yen per unit	The product must be registered as eligible for subsidies under the National Subsidy Program for Carbon Dioxide Emission Reduction Measures or the Mirai Eco Housing Program, etc.
Preparation of As-Built Drawings for Energy Efficiency Assessments	10 out of 10	100,000 yen per household	This refers to the preparation of as-built drawings of a residence for use in conducting energy efficiency assessments and similar activities.
Energy Efficiency Assessment and Labeling	10 out of 10	1.2 million yen per unit	・The assessment must evaluate the energy consumption performance and thermal envelope performance of the dwelling ・Labels must be created in accordance with the building energy efficiency labeling system; etc.

(2) Installation of renewable energy systems (new and existing homes)

We provide grants to owners of single-building rental properties that combine solar power generation with low-voltage bulk power supply to provide renewable energy to individual units, covering expenses related to solar power generation equipment and ancillary facilities for low-voltage bulk power supply.

Eligibility for Grants	Grant Amount	Upper limit	Requirements
Solar Power System (New Construction)	(3.6 kilowatts or less)		・The electricity generated by the solar power system must be available for use in all units of the rental housing where the system is installed. ・The system must be newly installed in a rental housing unit within Tokyo or on its premises, etc.
	180,000 yen per kilowatt	540,000 yen
	(More than 3.6 kilowatts but less than 50 kilowatts)
	150,000 yen per kilowatt	–
Existing Solar Power Generation System	(3.75 kilowatts or less)
	300,000 yen per kilowatt	900,000 yen
	(More than 3.75 kilowatts but less than 50 kilowatts)
	240,000 yen per kilowatt	–
Functional PV Overlay	Depending on the functional category	Up to 100,000 yen per kilowatt	In accordance with the functionality categories specified in the standards for solar power generation systems with superior functionality
Additional charge for mounting structure installation	200,000 yen per kilowatt	Generating capacity of less than 50 kilowatts	Limited to installation on flat roofs of rental housing, etc.
Additional Waterproofing Work	180,000 yen per kilowatt		Limited to installation on flat roofs of existing rental housing, etc.
Electricity meter	70,000 yen per unit	–	The electricity meter must have been certified in accordance with the Measurement Act, etc.
Data collection device	100,000 yen per building	–	Integration with a solar power generation system, etc.
Battery Storage System	100,000 yen per kilowatt-hour	1.8 million yen per unit	Items used for energy consumption in residential areas, etc.

2. Eligible Recipients

(1) Energy Efficiency (Existing Homes)

Owners of single-building rental properties that undergo energy efficiency assessments and insulation upgrades

(2) Installation of renewable energy systems (new and existing homes)

In order for owners of single-building rental properties
*(1) and (2) that install low-voltage bulk power supply systems to be eligible for subsidies under this program, the installation must be carried out by a business operator registered with the Tokyo Metropolitan Global Warming Prevention Activity Promotion Center (Cool Net Tokyo) of the Tokyo Metropolitan Environment Public Corporation.

3. Grant Pre-Application Period

May 29, 2026 – March 31 , 2027
*The program will close once the total amount of applications reaches the funding cap.
*Please be sure to sign a contract with the service provider only after your preliminary application has been accepted. Projects for which a contract was signed or construction began prior to the start of the reliminary application period are not eligible for the grant. However, for projects that were not previously subject to a preliminary application but for which a contract was signed between April 1, 2026, and June 30, 2026, applications will be accepted after the contract is signed.

4. Business Registration Period

May 29, 2026 – February 26, 2027
*To undertake projects eligible for this grant related to energy efficiency assessments, insulation upgrades, and the installation of renewable energy equipment, you must register with Cool Net Tokyo.
*If you have already registered as a business operator in fiscal year 2025, you do not need to register again.

5. Application and Performance Report Period

June 30, 2026 – March 31, 2027
*Please note that contracts with contractors will be signed after the preliminary grant application process is complete. Once construction is finished, please submit your combined grant application and performance report.
*Combined grant applications and performance reports for projects from fiscal year 2025 are accepted regardless of this timeframe.

6. Grant Application Desk

Cool Net Tokyo Renewable Energy Support Team, Apartment Building Section
Insulation and Renewable Energy Concentration Promotion Project for Rental Housing
Homepage for the project to promote insulation and renewable energy in rental housing (link to external site)

This project is an initiative to promote the “Tokyo 2050 Strategy.”
Strategy 20: Zero Emissions—”Maximizing Energy Efficiency”

Contact: (Regarding the subsidy program) Climate Change Countermeasures Division, Household Energy Measures Section , Bureau of the Environment Phone: 03-5388-3709 (Regarding application acceptance) Tokyo Metropolitan Global Warming Prevention Activity Promotion Center (Cool Net Tokyo), Tokyo Metropolitan Environment Public Corporation Phone: 03-6258-5317