Leave the installation of solar panels in Miura City, Kanagawa Prefecture to Kakeru Koumuten Co., Ltd.!
For
Solar Panel and Storage Battery Installation in
Miura City, Kanagawa Prefecture, trust Kakeru Koumuten!
Kakeru Koumuten is a specialized exterior renovation company based in Aoba Ward, Yokohama City.
As a company strong in roofing work, we are entrusted with solar panel installation and storage battery installation considering roofing and waterproofing!
“How to Choose a Solar Panel Contractor in Miura City”
“Costs for Solar Panel and Storage Battery Installation”
“Subsidies Available for Solar System Installation in Miura City”
We will also explain the above three points!
Installing solar panels carries the risk of issues such as “water leakage” and other troubles.
To avoid regrets, we recommend obtaining estimates from about three companies!
Table of Contents (Tap to Open/Close)
- Reasons Why Kakeru Koumuten is Chosen for Solar Panel Installation in Miura City, Kanagawa Prefecture
- Roof Inspection Before Installing Solar Panels
- Possible Subsidies and Grants Available in Miura City
- Price List for Solar Panel and Storage Battery Installation
- Breakdown of Installation Capacity, Equipment, and Construction Costs
- Self-Estimate and Profit Simulation for Solar Power Generation
- Customer Testimonials
- Case Studies of Solar Panel Installations
- How to Choose a Solar Panel Installation Company in Miura City, Kanagawa Prefecture
- Benefits of Introducing Solar Equipment
- Points to Note When Introducing Solar Power Generation
- How to Choose Solar Panels
- Frequently Asked Questions About Solar and Storage Battery Installation in Miura City
- If You’re Looking for a Solar Panel Installation Company in Miura City, Contact Kakeru Koumuten
- Characteristics of Miura City, Kanagawa Prefecture and Key Points for Solar Installation
- Service Area in Miura City, Kanagawa Prefecture
Reasons Why Kakeru Koumuten is Chosen for Solar Panel Installation in Miura City, Kanagawa Prefecture
The reasons our company is entrusted with solar panel installation by customers in Miura City, Kanagawa Prefecture include
one reason being that Kakeru Koumuten has a base in Kanagawa Prefecture,
and our unique strengths in solar panel installation that cannot be imitated by other companies, which have received high praise from many customers.
so we would appreciate it if you could compare our estimates with those of other companies.
Because we are confident, we welcome estimates from any number of companies!
1. We also handle exterior renovations beyond solar panel installation!
Problems such as leaks that occur during solar panel installation may be caused by insufficient checks on the roof and waterproofing at the installation site.
Even if you are knowledgeable about solar panels, there are cases where the roof and waterproofing at the installation site are outside your expertise, so caution is necessary.
It is reassuring to have knowledge about the roof to avoid maintenance and troubles after installation!
Kakeru Koumuten Co., Ltd. is strong in roofing work and can also detach and attach solar panels in-house, allowing for quick responses to maintenance and urgent troubles after solar panel installation!
2.Facilities Specialized in Exterior Renovation
Kakeru Koumuten Co., Ltd. has organized the following warehouses and material storage areas to provide low-cost, high-quality solar work and exterior renovations.
We have established five bases centered around Yokohama City, Kanagawa Prefecture for material storage and showrooms.
In-house Ownership of Scaffolding Materials
To ensure safety during work on the roof, we own the necessary scaffolding materials for temporary scaffolding according to construction conditions, allowing us to assemble scaffolding ourselves.
By performing scaffolding work with our own scaffolding team instead of outsourcing, we can also reduce the cost of scaffolding work.
We have scaffolding materials for approximately 50 single-family homes!
Even in Miura City, which has a wide range of environments from plateaus and hilly areas to coastal residential areas, our own scaffolding team will plan the scaffolding according to the site conditions.
Storage of materials in our large warehouse
We store roofing materials and paints, and we can also store removed solar panels.
By ordering a large quantity of materials at once, we canpurchase materials at a lower cost!
Additionally, we always have a stock of roofing materials, so we can providequick responses in emergencies!
Sorting and transportation of waste materials in-house
The installation of solar panels often involves roofing work, generating various waste materials such as paint, wood, and metal.
By sorting and recycling waste materials, we can significantly cut waste disposal costs.
Exterior remodeling dedicated showroom
In the showroom, not only can you have meetings, but you can also
check the actual foundation brackets for solar panels and see how they are installed on the roofing materials!
It is also possible to simulate the revenue and installation costs when introducing solar panels!
Since roofing and exterior wall work often accompany each other, we also provide samples of roofing materials and models that explain the structure in detail!
3.All Work Performed by Our Own Team
One of Kakeru Koumuten’s major strengths is all work performed by our own team.
By having a consistent system from inquiry to completion, Kakeru Koumuten can provide high-quality roof renovations at reduced costs.
Additionally, one representative will handle everything from the estimate to the completion of the work.
Since the person in charge does not change, whether it is the sales representative or the construction management representative, smooth communication is possible.
We can perform consistent in-house work from temporary scaffolding installation to exterior wall painting and roof renovation!
4. Various Permits and Skilled Workers
We have obtained permits for the construction industry and for the collection and transportation of industrial waste!
We also have nationally certified sheet metal workers and painting specialists, and we are confident in our construction techniques.
We are capable of handling large-scale roofing work for factories and other facilities!
5. Warranty and Aftercare
In addition to the manufacturer’s warranty, our solar panel installation work comes with our own workmanship warranty (leakage warranty)!
(The workmanship warranty for solar panel installation is 10 years. Depending on the condition of the roof before installation, we may not be able to provide a warranty unless a roof renovation is performed. The workmanship warranty is separate from the manufacturer’s product warranty, and the coverage and conditions vary based on the warranty details.)
Aftercare maintenance is available every year, and we send out notification DM each year.
If you have any questions about the warranty, please click on the image above!
6. Flexible and Prompt Response
Our company is equipped to handle various roof troubles and situations.
Even if we cannot access the roof from high places, we can respond using a drone!
During leakage investigations, we can also conduct inspections using a thermal imaging camera.
If the power generation of the solar panels decreases due to dirt, we can also perform cleaning with a specialized brush.
We will respond according to the customer’s wishes.
7. Human Resource Development
We create various roof models for skill enhancement and conduct practical training.
Since the construction methods vary depending on the shape and slope of the roof, we regularly provide technical training to ensure that each staff member can handle various cases.
8. Creation of Easy-to-Understand Materials and Simulations
At Kakeru Koumuten Co., Ltd., in addition to “estimates”, “layout diagrams”, and “power generation simulations”, we also provide a “solar installation guidebook” and a “financial simulation” that takes into account loan interest rates and electricity costs.
The financial simulation can be created for projected cumulative income and expenses over 20 to 30 years.
Even customers who are not familiar with solar installations will find the materials easy to understand, including points to consider and potential drawbacks!
We encourage you to obtain comparative estimates and review plans from other companies!
Roof Inspection Before Installing Solar Panels
Once solar panels are installed, they will remain on the roof for 20 or 30 years.
It is crucial to confirm “whether it is safe to install them directly on the current roof” before installation, as this is the key point to prevent leaks and unnecessary expenses!
Kakeru Koumuten, specializing in roofing work, has summarized the items to check before installation.
| 1. Type of roofing material and age | The method of securing varies depending on the roofing material, such as slate, tiles, metal roofs, or flat roofs (roof waterproofing). If the remaining lifespan of the roofing material is short, we may suggest a roof renovation first. |
| 2. Condition of the substrate and waterproof sheet | If the sheathing or roofing (waterproof sheet) beneath the roofing material is damaged, it can affect the fastening strength and waterproofing. We also check for signs of leaks. |
| 3. Orientation, slope, and shadows of the roof | The orientation and slope of the roof surface, as well as shadows from neighboring houses, trees, and utility poles, can affect power generation. We create a layout diagram from the drawings and the site, and you can confirm it through the power generation simulation. |
| 4. Shape of the roof and installable area | The number of panels (installation capacity) that can be installed is determined by the shape and size of the roof. The number of panels that can be installed varies depending on their size, so we compare based on the overall output of the roof. |
| 5. Method of securing and waterproofing details | We check whether the method involves drilling holes in the roofing material for fastening or using brackets to secure the roofing material. The method of securing varies by technique, so please confirm the waterproofing treatment of the fastening parts during the estimate. |
| 6. Weight of the roof | The roof will become heavier due to the panels. After investigating the existing roof, substrate, and load-bearing capacity, replacing with lighter roofing materials may be an option if necessary. |
| 7. Location of equipment installation and wiring | We confirm the installation locations for the power conditioner and storage batteries, as well as the wiring route to the distribution board. The length of the wiring also affects costs. |
Securing Methods and Checkpoints by Roofing Material
| Roof Material | Main Fixing Method | Pre-Installation Check Points |
|---|---|---|
| Slate Roof | Varies by method (methods such as fixing brackets to the roof material and substrate with screws, etc.) | Waterproof treatment of fixed parts, cracks and deterioration of slate, condition of the substrate. If deterioration is advanced, consider roof overlay (cover method) or replacement first. |
| Tile Roof | Fixed with brackets and methods suitable for the type of tile (even methods that do not drill holes in the tiles will fix to the substrate) | Type and condition of tiles, substrate, load-bearing capacity. Depending on the investigation results, there may be methods to replace with lighter roofing materials before installation. |
| Metal Roof (Horizontal and Vertical) | Fixed with catch-type brackets that grip the roof material (depends on the combination of roof material and brackets) | Whether the roof material and brackets are compatible, installation conditions from the roof material manufacturer. If compatible, methods that do not drill holes may be available. |
| Flat Roof / Rooftop | Fixed by installing a framework | Type and deterioration status of the waterproof layer, waterproofing around the framework. Consider in conjunction with the timing of waterproofing work. |
If you carry out roof renovations 10 to 20 years after installation, there will be additional costs for removing and reinstalling solar panels. If the roof is deteriorating, it may be more cost-effective in the long run to renovate to a highly durable roofing material before installation.
Kakeru Koumuten Co., Ltd. specializes in roofing work and can also handle the removal and reinstallation of solar panels in-house, so please consult us according to the condition of your roof!
▶ Click here for roof renovations in Miura City, Kanagawa Prefecture
Potential Subsidies and Grants in Miura City, Kanagawa Prefecture
If you introduce solar panels or storage batteries in Miura City, there is a possibility that you may be eligible for programs from the “National Government,” “Kanagawa Prefecture,” and “Miura City.”
The following information is based on the official pages of each program as of October 6, 2026. The application status may change depending on the budget and application period, so please check the latest information before contracting or starting work.
Eligibility Conditions and Application Timing for Subsidy Programs
| Program | Main Eligibility Conditions | Subsidy Amount | Application Period & Status |
|---|---|---|---|
| Miura City “Key Measures Acceleration Project Subsidy” (for households, self-owned) | Individuals installing equipment on their own property in residential areas of the city (must not have any tax arrears). Equipment that does not receive FIT or FIP certification, and must consume more than 30% of the generated electricity on-site. Storage batteries are only eligible if introduced simultaneously with solar power (storage batteries alone are not eligible). Pre-construction before the city’s grant decision is generally not allowed. | Solar: 70,000 JPY/kW (amounts under 1 kW are rounded down) Storage battery: 1/3 of the storage system + construction cost (excluding tax) (maximum 141,000 JPY/kWh) |
Applications accepted from May 1, 2026, to January 15, 2027 (first-come, first-served, ends when budget is reached) Against a budget of 10,569,000 JPY, the application amount as of October 2, 2026, is 6,432,000 JPY. |
| Kanagawa Prefecture “Fiscal Year 2026 Kanagawa Prefecture Residential Solar Power and Storage Battery Installation Subsidy” | For single-family homes or multi-family residences in the prefecture, must install both solar power and storage batteries in a seismically secure home. Applications must be made by the individual, and construction can only begin after grant approval. | Solar: 70,000 JPY/kW Storage battery: 150,000 JPY/unit |
Phase 1: May 11, 2026, to June 30, 2026 Phase 2: September 7, 2026, to September 30, 2026 (first-come, first-served) Phase 2 application period has ended. Please check the prefecture’s official page for future recruitment. |
| National “DR Home Storage Battery Project” (Fiscal Year 2025 Supplement) | New installation of home storage systems that can be used for DR (demand response) with registered products. | Calculated based on an initial effective capacity of 1 kWh at 34,500 JPY (subsidy rate within 30% and maximum 600,000 JPY per application). | As of May 29, 2026, the budget has been reached, and public recruitment has ended (applications are currently not accepted). |
| National “Mirai Eco Housing 2026 Project” (Renovation) | Storage batteries are one of the eligible facilities, but must be combined with essential works such as insulation renovations of windows (openings) and the structure; applications cannot be made for storage battery installation alone. Solar panels are not included as eligible facilities. | Storage battery: 96,000 JPY/unit | Ends as soon as the budget limit is reached. Please check the official site for application status. |
| Kanagawa Prefecture “Fiscal Year 2026 Kanagawa Prefecture Self-Consumption Renewable Energy Installation Subsidy” | Corporations and individuals filing blue returns (individual residences are not eligible). Solar power must have a generation capacity of 10 kW or more, for business facilities, and equipment that does not receive FIT or FIP certification, etc. | Solar: 80,000 JPY/kW, etc. Storage system: 50,000 JPY/kWh (maximum 5,000,000 JPY). |
Recruitment ended on September 3, 2026 (application amount reached the budget). |
In Miura City, the principle is that construction cannot begin before the city’s grant decision, and for Kanagawa Prefecture’s housing subsidies, the condition is that construction must start after receiving the “grant decision.” If construction begins beforehand, it may be excluded from eligibility. Additionally, Miura City’s subsidy requires that the equipment does not receive FIT or FIP certification and that more than 30% of the generated electricity is consumed on-site. It is necessary to confirm the possibility of combining city and prefectural subsidies for each system. Please check before contracting and starting construction, as applying does not guarantee that a grant will be awarded.
At Kakeru Koumuten Co., Ltd., we will guide you on the eligibility conditions and business requirements for each system after confirming them.
Miura City “Accelerated Measures Subsidy for Key Projects” (Solar Power Generation Equipment and Storage Batteries)
In Miura City, subsidies are provided for those who install solar power generation equipment and storage systems on their own residential or business properties. The condition is that there are no outstanding municipal taxes, and the equipment must not receive FIT or FIP certification and must consume more than 30% of the generated electricity on-site.
The subsidy amount for households is 70,000 yen per kW for solar power generation (the equipment output is rounded down to the nearest whole kW), and for storage batteries, it is one-third of the storage system and construction costs (excluding tax), with a maximum of 141,000 yen/kWh. Storage batteries are eligible only if they are installed simultaneously with solar power; installations of storage batteries alone are not eligible.
Applications will be accepted from May 1, 2026, to January 15, 2027, and will end once the budget is reached on a first-come, first-served basis. The budget amount is 10,569,000 yen, and as of October 2, 2026, the application amount is 6,432,000 yen. Pre-construction before the city’s grant decision is generally not allowed, so it is important to confirm the timing of construction and the order of applications before contracting.
👉 Click here for the official Miura City page
National Subsidy “DR Home Storage Battery Project (Support Project for the Introduction of Home Storage Systems for DR Resources)”
The national government has been implementing the “DR Home Storage Battery Project” to support the installation of home storage batteries.
This program targets those who are introducing new registered products for storage systems that can be used for demand response (DR), and in the fiscal year 2025 supplementary budget, the subsidy amount was determined based on a standard amount of 34,500 yen per kWh of initial effective capacity, with a subsidy rate of up to 30% and a maximum of 600,000 yen per application. There are conditions such as that contracts or orders made before the grant decision are not eligible.
However, the fiscal year 2025 supplementary budget reached its application budget on May 29, 2026, and the public recruitment has ended (the previous fiscal year’s supplementary budget also ended public recruitment on July 2, 2025). Applications are currently not possible, so please check the official site for future public recruitment.
Additionally, there are currently no subsidies confirmed for the installation of solar panels on existing homes.
👉 Click here for the official DR Home Storage Battery Project website
Kanagawa Prefecture “Reiwa 8 Year Kanagawa Prefecture Residential Solar Power Generation and Storage Battery Installation Subsidy”
In Kanagawa Prefecture, subsidies are provided for those who install both “solar panels” and “storage batteries” in their homes.
The subsidy amounts are 70,000 yen per kW of solar power generation output and 150,000 yen per storage system.
For example, if you install a 4kW solar panel and one storage battery, the calculation for the subsidy amount would be 4kW × 70,000 yen + 150,000 yen = 430,000 yen.
Conditions include that the storage system must be a registered product, if construction begins before the subsidy decision is made, it will be excluded, and the application must be made by the individual (proxy applications by contractors are not allowed). Additionally, the targeted homes must ensure seismic performance. Please check each subsidy program for compatibility with other subsidy systems, as this may vary.
For the Reiwa 8 year, the first application period (May 11 – June 30) and the second application period (September 7 – September 30, first-come-first-served) have been conducted, and the second period has reached its application deadline. For future recruitment, please check the official page of Kanagawa Prefecture.
👉 Click here for the official page of Kanagawa Prefecture
Kanagawa Prefecture “Reiwa 8 Year Kanagawa Prefecture Self-Consumption Type Renewable Energy Installation Subsidy” (for businesses)
Kanagawa Prefecture also provides subsidies for businesses that install “self-consumption type” facilities that use electricity generated from solar panels.
Eligible applicants are corporations or individual business owners who file blue returns, and installations in individual residences are not eligible.
Conditions include that the solar power generation must have an output of 10kW or more, supply electricity to business facilities within the prefecture, and not be certified under FIT/FIP.
The subsidy amount is 80,000 yen per kW for solar power generation and 50,000 yen per kWh for the accompanying storage system (with a maximum of 5 million yen).
As the application amount reached the budget amount for the Reiwa 8 year, applications were closed on September 3, 2026.
Businesses considering the installation of solar panels on commercial buildings in Miura City should check the official page of Kanagawa Prefecture for the next recruitment.
👉 Click here for details
Solar Panel Installation and Storage Battery Installation Price List
⇧Service Menu | For Costs Related to Solar Panel and Battery Installation, Click Here
⇧Service Menu | For Costs Related to Solar Panel Removal and Water Heater Dismantling, Click Here
Breakdown of Installation Capacity, Equipment, and Construction Costs
The costs for solar panels and batteries should be confirmed by separating them into “Equipment Costs (Device Costs)” and “Construction Costs”.
Even for the same “Complete Solar Panel Installation,” the amount can vary significantly depending on the installation capacity, equipment grade, and roof condition.
Considerations for Installation Capacity (kW) and Battery Capacity (kWh)
The installation capacity of solar panels is determined by “Output of One Panel (W) × Number of Panels”, with the unit being kW (kilowatts). Batteries are compared based on the amount of electricity they can store, represented in kWh (kilowatt-hours).
The amount of kW that can be placed on the roof varies for each house based on the roof’s shape, orientation, and size. At Kakeru Koumuten, we create layout diagrams from blueprints and on-site surveys to present the installation capacity.
On our pricing page, we list solar panel installation costs as approximately 800,000 JPY to 1,200,000 JPY for 3 to 5 kW, and 1,200,000 JPY to 1,900,000 JPY for 6 to 10 kW. (These are just estimated amounts and may vary based on wiring length, scaffolding range, existing roofing materials, panel layout, etc.)
▶ Installation Menu | Costs for Solar Panel and Storage Battery Installation
Items to Confirm on the Estimate (Cost Verification)
When comparing estimates from different companies, it is common to compare different capacities and equipment. Please check if the following items are clearly stated in each company’s estimate!
| 1. Solar Panels | Manufacturer, model number, output per panel (W), number of panels, total installation capacity (kW) should be listed. |
| 2. Power Conditioner | Manufacturer, model number, capacity, number of units, installation location (indoor/outdoor). Also confirm if it is a type that controls the storage battery together. |
| 3. Storage Battery | Manufacturer, model number, capacity (kWh), range of use during power outages (entire house or specific circuits), installation location. |
| 4. Mounting Frame and Hardware | Name of the hardware suitable for the roofing material and the fixing method (whether it is a method that drills holes or a method that clamps and fixes). |
| 5. Wiring and Electrical Work | Wiring route and length, work around the distribution board, and whether there is a monitor to check the power generation amount. |
| 6. Roof Reinforcement and Waterproofing | Details of waterproofing treatment at the fixing points, and whether necessary roof repairs and substrate reinforcements are included. |
| 7. Applications | How much support is included for applications to the power company, feed-in tariff (FIT) certification applications, and subsidy applications. |
| 8. Scaffolding | Scope and quantity of scaffolding. If it is simultaneous with roof work or exterior painting, check that the same scope and quantity are not double-counted. |
| 9. Removal and Disposal | Whether the removal of existing solar thermal water heaters or old panels and disposal costs for waste materials are included. |
| 10. Tax Classification and Warranty | Whether the price is tax-inclusive or tax-exclusive, conditions under which additional costs may arise, and details and duration of manufacturer and workmanship warranties. |
If the capacities are different, both the price and power generation will change. Kakeru Koumuten Co., Ltd. welcome comparisons, so if you bring estimates from other companies, we will explain the differences for each item!
Self-Estimate and Profit Simulation for Solar Power Generation
With the simulator above,
you can get an estimated quote and a financial simulation for up to 30 years!
If you know the total installation capacity of solar panels on the roof and the capacity of the storage battery, you can obtain an estimated quote and financial simulation!
*The simulation results are estimates. Actual financial results may vary based on assumptions such as electricity rates, self-consumption ratios, selling prices, and costs for equipment inspection and replacement.
Customer Feedback
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customer reviews
Asao-ku, Kawasaki City | We received reviews about the ridge cap and rain gutter replacement work!
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customer reviews
Kohoku-ku, Yokohama | We received reviews about the roof overlay (cover method)!
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customer reviews
Kohoku-ku, Yokohama | We Received Reviews About Exterior Painting!
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customer reviews
Hodogaya-ku, Yokohama | We received reviews about our exterior fence construction!
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customer reviews
Tsurumi-ku, Yokohama | We received reviews about roof and exterior wall painting, as well as metalwork and rain gutter replacement work!
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customer reviews
Higashiyamato City, Tokyo | We received reviews about exterior painting and roof overlay (cover method)!
Case Studies of Solar Panel Installations
| Work Details |
| Solar Panel Installation Battery Installation |
| Existing Roofing Material |
| Horizontal Metal Roof (Super Galtect) |
| Installation Capacity |
| Solar Panel: 4.3kW Battery: 5kWh |
| Base Mounting Hardware Used |
| Niigata Manufactured / Aluminum Catch Type Hardware |
| Fixing Method & Waterproofing Details |
| Fixed using catch type hardware to grip the horizontal metal roof (Catch Method) |
| Price Range |
| 2,200,000 JPY～2,300,000 JPY *Due to the grant being provided, the actual burden amount is approximately 1,000,000 JPY Estimated recovery period for construction costs: about 8 to 9 years (self-consumption) *The grant amount and recovery estimate are based on the system and calculations at the time of construction, and may differ under the current system. |
| Construction Period |
| Approximately 3 days |
| Completion Month |
| April 2025 |
| Inquiry Details |
| I am considering the installation of solar panels and storage batteries. I heard that grants are available, and I would like to know how much can be provided. |
Our Proposal
We visited to provide an estimate and created a layout diagram for the solar panels from the drawings!
The layout diagram shows the arrangement of solar panels when placed on the roof.
Since we can also determine the installation capacity, it allows for power generation simulations and financial simulations.
We have also understood the expected amount of the grant, so we explained it to the customer along with the estimate!
How to Choose a Solar Panel Installation Contractor in Miura City, Kanagawa Prefecture
There are many solar panel installation companies that serve Miura City, Kanagawa Prefecture, and you may be unsure which company to choose.
Therefore, when requesting solar panel installation and battery installation work, let’s check the following 4 points.
● They should have extensive knowledge not only about solar panels but also about roofs.
● Confirm whether there is a warranty and after-sales maintenance.
● Obtain estimates from multiple companies (3 companies as a guideline).
● Check if they provide support for subsidy applications.
By confirming the above 4 points, you will be able to choose a reliable company.
They should have knowledge not only about solar panels but also about roofs.
Improper installation of solar panels can be caused by a lack of knowledge and verification regarding roofs and waterproofing.
While knowledge about solar panels is certainly important, understanding the roof and waterproofing at the installation site of the solar panels is also crucial.
⚠︎Examples of troubles caused by insufficient verification of roofs and waterproofing
・Solar panels were installed on a severely deteriorated roof, leading to leaks.
・Solar panels were installed on a roof with a short lifespan, requiring a remodel to detach and reattach the solar panels within a few years.
・Misjudgment of the type of waterproofing led to incorrect treatment and subsequent leaks.
and more
When installing solar panels, understanding the condition and type of the existing roof allows you to avoid unnecessary expenses and unexpected troubles.
▶ Go to “Roof Verification Before Installing Solar Panels” in this article
Confirm whether there is a warranty and after-sales maintenance.
When choosing a solar installation company, let’s confirm the warranty availability. It is important to check not only the duration of the warranty but also the coverage, exclusions, and cost conditions.
Solar panels and batteries come with a manufacturer’s warranty, but also check for the availability of a workmanship warranty in case leaks occur after installation!
For companies that offer a workmanship warranty, if leaks occur after installation, they may cover the repairs under the warranty, as long as it is within the warranty period and conditions.
Additionally, some contractors offer after-sales service separate from warranties, so be sure to check if the contractor you are considering has after-sales service.
Changes or damages on the roof may occur in areas that are not visible, so you may not notice them yourself.
By conducting inspections of these hidden areas during after-sales maintenance, you can more easily prevent major repairs or breakdowns by discovering issues early!
Kakeru Koumuten Co., Ltd. provides a rain leak warranty as part of the workmanship warranty for solar panel installations. (The warranty for solar panel installations is 10 years, and depending on the condition of the roof before installation, it may not be possible to provide a warranty without performing roof renovations.)
We also conduct after-sales maintenance and send out DM every year!
Please check the DM, and if you wish, we will visit you for after-sales maintenance!
Obtain estimates from multiple contractors (3 companies as a guideline)
When requesting solar panel installation, be sure to obtain estimates from multiple contractors.
Even for the same manufacturer and the same construction content, costs may vary, as well as warranties and after-sales services.
Additionally, obtaining multiple estimates makes it easier to negotiate prices.
To request services from your preferred contractor at a lower price, we recommend obtaining estimates from multiple contractors.
When comparing estimates, please check carefully for:
“Verification of estimate items”
“Types of solar panels”
“Warranties and after-sales services”
Make sure to compare these details closely! If the quality of the auxiliary materials is low or if steps are skipped, costs can be reduced, so avoid making decisions based solely on price!
▶ To “Breakdown of Installation Capacity and Equipment/Construction Costs” within this article
Check if they provide support for subsidy applications
Subsidies may be available for solar panel installations and battery installations, but if the order of procedures is incorrect or if there are deficiencies in the documents, the subsidy may not be granted.
For systems like Kanagawa Prefecture’s housing subsidies, where applications cannot be submitted by the contractor and must be done by the individual, it is reassuring to have a contractor that supports the preparation of necessary documents and the flow of procedures.
Be sure to complete the procedures specified for each system (for the prefectural housing subsidy, this means obtaining a grant decision) before proceeding with the construction!
For the prefectural housing subsidy, after the construction is completed, a performance report must be submitted, and the grant will be issued after review! (The flow of procedures varies by system)
▶ To “Subsidies and Grants That May Be Applicable in Miura City” within this Article
Benefits of Introducing Solar Power Equipment
The benefits of introducing solar panels are summarized in the following 5 points!
Benefit 1: Economic Advantage
The biggest advantage of introducing solar panels is the economic benefit!
Although the selling price of electricity has decreased compared to ten years ago, by consuming the electricity generated, you can reduce the amount of electricity purchased from the utility company and gain benefits!
As electricity prices rise, the ability to cover your consumption with solar power becomes attractive!
If you plan to use the generated electricity at night, the installation of a storage battery is essential!
For residential use (under 10kW), the selling price (FIT) from certifications after October 2025 is set at “24 yen/kWh for the first 4 years, and 8.3 yen/kWh from the 5th to the 10th year.” The same price will apply for the 2026 fiscal year. After the 5th year, it is generally more advantageous to use the electricity at home (self-consumption), making the combination with a storage battery a viable option.
👉 Ministry of the Environment | For purchase prices, periods, etc., click here
Benefit 2: You Can Utilize Subsidies!
The conditions and amounts of subsidies vary by prefecture and municipality, but if you meet the conditions, you may be able to utilize subsidies!
Reducing the actual burden amount through subsidies is a significant advantage!
In the case of Miura City, there may be subsidies available from the city and Kanagawa Prefecture, so please check the latest application status.
Benefit 3: Environmentally Friendly!
Solar power generation has low carbon dioxide emissions and reduces dependence on fossil fuels, contributing to the mitigation of global warming.
Solar panels themselves do not produce noise or exhaust gases during the generation process, making them an environmentally friendly method of power generation. (However, devices like power conditioners may produce operational noise.)
Benefit 4: Heat Insulation Effect is Expected!!
By installing the panels on the roof or rooftop, they block direct sunlight from hitting the roof.
Especially in summer, it can help reduce the temperature rise of the roof, providing expected heat insulation effects!
(Note that this does not improve the building’s insulation performance itself.)
Benefit 5: Electricity can be used even during power outages!!
If a storage battery is installed, it becomes possible to use electricity even during emergencies like power outages!
Even without a storage battery, if you have a power conditioner with autonomous operation functionality, you may be able to use electricity from a dedicated outlet during daytime generation.
(Note that the devices, output, and duration that can be used during a power outage vary depending on the model and wiring method.)
What points should be noted when introducing solar power generation?
Next, we will explain the “three points to note” when installing solar panels!
Point 1: Maintenance costs can be incurred
A particularly overlooked maintenance cost is for the roof where solar panels are installed.
If you perform roof renovations 10 to 20 years later, there will be costs for removing and reinstalling the solar panels.
If the existing roof is deteriorating, it is reassuring to renovate it with durable roofing materials before installing solar panels!
Additionally, there will be costs for regular inspections of the equipment, repairs or replacements of the power conditioner, and updates due to the deterioration of the storage battery.
It would be reassuring to request a simulation that also considers maintenance costs before introducing solar panels!
Point 2: The risk of leaks increases depending on the roofing material
The fixing methods for slate roofs and tile roofs vary by construction method, but in methods that fix brackets to the roofing material or substrate with screws, waterproofing of the fixed parts is crucial.
In methods that involve making holes in the roof, the risk of leaks inevitably arises.
Of course, we will ensure proper waterproofing, but if you are concerned about making holes, one option is to replace the roofing material with a metal roof and fix the solar panels using the catch method. (The catch method has compatibility conditions between the roofing material and brackets, and it cannot be used with all metal roofs.)
Catch-type base metal fittings for horizontal metal roofs
Note 3: The roof will become heavier
Since solar panels will be installed, the roof will become heavier. After investigating the existing roof, substrate, and load-bearing capacity, switching to a lighter roof may also be an option if necessary.
How to Choose Solar Panels?
There are many manufacturers of solar panels, and their output and costs vary.
It is not simply a matter of “this manufacturer has the best solar panels”; it is important to choose solar panels that are suitable for your life plan and building!
Here are some points to consider when comparing solar panels!
How to Choose 1: Compare by Total Output of the Roof
When installing solar panels on the roof, it is important to consider how much power can be generated in a limited area, and the more power generated, the better!
Solar panels come in various sizes and outputs depending on the manufacturer.
For example, a 350W output panel and a 400W output panel may seem at first glance that the higher output panel is better.
However, if the size of the panel does not fit well with the roof, there may be cases where “20 panels of 350W can be installed” and “15 panels of 400W can be installed,” leading to different numbers of panels that can be installed on the same roof due to size differences.
400W×15 panels = 6kW (total output of the roof)
350W×20 panels = 7kW (total output of the roof)
As shown above, even if the output of one panel is lower, the total output of the roof may be higher!
It is important to consider the total output of the roof rather than the output of a single panel!
*The above calculations are for total output (kW). The actual power generation amount (kWh) will vary depending on conditions such as roof orientation, slope, and shading.
How to Choose 2: Compare by Degradation Rate of Solar Panels
Solar panels have a degradation rate, and their output gradually decreases over 10 years and 20 years.
The degree of output reduction after long-term use varies by product. The manufacturer’s output guarantee value is a standard figure for warranty purposes and does not indicate the actual degradation rate or power generation amount.
By not deciding solely based on initial output and considering the degradation rate, you can choose solar panels without regrets!
How to Choose 3: Compare by Warranty Period
There are several types of warranties for solar panels, including “output warranty,” “natural disaster warranty,” and “system warranty,” and the warranty periods vary by manufacturer.
Regarding the output warranty, some manufacturers offer a 30-year warranty while others provide a 10-year warranty, so it varies widely!
Since a longer warranty is generally better, let’s check the warranty periods and conditions of the manufacturers you are considering!
Frequently Asked Questions about Solar Power and Battery Installation in Miura City
We have compiled common questions from customers considering the installation of solar panels and batteries in Miura City. (Tap to open the answers)
How much does it cost to install solar panels and batteries in Miura City, Kanagawa Prefecture?
The cost varies depending on the installation capacity, equipment, and condition of the roof. In the above construction example (solar panel 4.3kW + battery, completed in April 2025), it was 2.2 million yen to 2.3 million yen.
Guidelines for different capacities are published on the solar panel and battery installation pricing page. We will create a layout diagram from the drawings and on-site survey and provide a free estimate!
Are there any subsidies available for solar power and battery installation in Miura City?
As of October 6, 2026, Miura City’s “Priority Measures Acceleration Project Subsidy” (for households: 70,000 yen/kW for solar power and 1/3 of the battery cost with a maximum of 141,000 yen/kWh) is currently accepting applications on a first-come, first-served basis (as of October 2, 2026, the application amount was about 60% of the budget). The Kanagawa Prefecture subsidy (70,000 yen/kW for solar power and 150,000 yen per battery) is approaching the application deadline for the second term of fiscal year 2026, and the national DR household battery project has ended its public recruitment.
Since the application status may change, please refer to the subsidy and grant section and consult with us before signing a contract.
Can I apply for subsidies after the construction is completed?
For many programs, procedures are required before construction. Miura City’s subsidy states that “preliminary work cannot begin before the city’s grant decision,” and Kanagawa Prefecture’s subsidy requires “construction to begin after the grant decision,” so if you install it beforehand, you may be excluded from eligibility.
The order of procedures varies by program, so please confirm before signing a contract or starting construction.
Can solar panels be installed on a slate roof? I’m worried about leaks.
It is possible to install on a slate roof, but it is necessary to check the condition of the roofing material and substrate. The fixing method varies by construction method, and if the method involves fixing brackets to the roofing material or substrate, waterproofing treatment of the fixed parts is essential.
Kakeru Koumuten Co., Ltd. is a specialized exterior renovation company strong in roofing work, so we will check the condition of the roof before installation and suggest methods such as roof overlay (cover method) or complete replacement if deterioration is advanced.
My roof is old. Should I do a roof renovation first?
It depends on the condition of the roof. If a roof renovation is needed within 10 to 20 years after installation, there will be additional costs for removing and reinstalling solar panels. If the remaining lifespan of the roof is short, renovating to a highly durable roofing material before installation may help reduce total costs.
Please consult us on how to proceed with the installation after checking the condition of the roof through a site survey!
Should I install a storage battery together with the solar panels?
If you want to use the generated electricity at night or prepare for power outages, simultaneous installation is recommended. The selling price for electricity will be 8.3 yen/kWh after the fifth year, making it more advantageous to use it at home rather than selling it.
Additionally, Kanagawa Prefecture’s subsidies require the simultaneous installation of solar panels and storage batteries, and subsidies in Miura City also apply only when the storage battery is installed at the same time as the solar panels (installation of the storage battery alone is not eligible). You can compare “solar panels only” and “solar panels + storage battery” through a financial simulation.
How many kW can be installed on my roof? Is it okay for north-facing roofs or roofs with shadows?
The capacity that can be installed varies depending on the shape, orientation, and size of the roof. At Kakeru Koumuten, we create a layout diagram from the drawings and site survey and provide you with the installation capacity and power generation simulation.
Miura City has a wide range of locations, including northern plateaus, central hilly areas, and coastal residential areas, and the way shadows are cast by neighboring houses, trees, and elevation differences varies from house to house. You can check the expected power generation through the power generation simulation.
How long will the construction period be?
In the above construction example (solar panel 4.3 kW + storage battery), it took about 3 days. The duration may vary if roofing work is done simultaneously or depending on the shape of the roof and installation capacity.
Please note that additional time is required for applications for subsidies and power companies, so please consult us as soon as possible.
What is the current selling price (FIT)?
For residential use (less than 10 kW), the selling price from certifications after October 2025 will be 24 yen/kWh for the first 4 years, and 8.3 yen/kWh from the 5th to the 10th year, and the same price will apply for the 2026 fiscal year.
The idea is to recover initial costs more quickly in the first 4 years and then focus on self-consumption. Kakeru Koumuten provides a financial simulation that considers loan interest rates and electricity costs.
Can you handle maintenance and inspections after installation?
Yes, we can. Kakeru Koumuten sends out annual after-service maintenance notices via DM and visits customers who wish to have inspections. We can also clean solar panels with a special brush if the power generation is reduced due to dirt.
The roof is a part that is difficult to check by yourself, so if you have any concerns, please feel free to consult us.
Can you also handle renovations for roofs that already have solar panels installed?
Yes, it is possible. Kakeru Koumuten Co., Ltd. can detach and reattach solar panels in-house, allowing us to remove the panels, perform roof overlay (cover method) or re-roofing, and then reinstall them consistently. The removed panels can be stored in our own warehouse.
For costs, please refer to the solar panel detachment and water heater removal pricing page.
If you are looking for a solar panel installation contractor in Miura City, please consult Kakeru Koumuten
Our company handles a wide range of exterior renovations, including roof work and wall work, in Miura City, Kanagawa Prefecture, along with solar panel installations.
We receive many requests from customers, including renovation companies and real estate agencies, who have contacted us!
Kakeru Koumuten promises “high-quality renovations at low costs”, and we have received great feedback from many customers.
We continue to update our construction performance each year, and we will strive to improve quality to satisfy even more customers in the future.
Our company can perform all exterior renovations, not only roof overlay and re-roofing but also partial roof repairs, exterior painting, and exterior cover methods.
We are also happy to handle small jobs like partial repairs and rain gutter cleaning!
In urgent cases such as leak repairs, we may be able to provide emergency measures without setting up scaffolding, as long as safety can be ensured, so please consult us!
“I want to know about recommended solar panels”, “I want to keep costs down as much as possible”, “I just want an estimate for now”, we will provide optimal solutions for specific requests.
We will never propose unnecessary work that prioritizes profit!
We always stand in the customer’s position and will propose the best construction plan!
We are confident that we will not be outdone in terms of cost, quality, and organization compared to other companies in exterior construction!
We are confident, so we welcome competitive quotes!
Estimates are completely free, and if you find our company to be inferior to others, you are free to decline!
Characteristics of Miura City, Kanagawa Prefecture, and Points of Solar Work
Miura City is located at the southern tip of the Miura Peninsula, which separates Tokyo Bay and Sagami Bay. According to the city’s official documents, the area is approximately 31 km², and the coastline, featuring sandy beaches, rocky shores, and inlets, is about 42.9 km long.
Below are the characteristics of Miura City and points to consider when installing solar panels and storage batteries. (Tap to open)
View the characteristics of Miura City and points for solar construction
■ A city surrounded by the sea. Check installation conditions for homes near the sea
The appearance of Miura City (official city document) states that Miura City is located at the southern tip of the Miura Peninsula, separating Tokyo Bay and Sagami Bay, with a coastline of about 42.9 km. In areas close to the sea, the installation conditions for salt damage areas set by manufacturers vary by model. When providing estimates, we will confirm the installation location and model conditions together.
■ A region with strong winds. Check the panel fixation method and mounting frame
The same official document mentions that Miura City is also known for its strong winds. When installing panels on the roof, it is important to securely fix them with brackets suitable for the roofing material and ensure waterproofing at the fixation points. In locations prone to wind effects, we will also check the specifications of the mounting frame and fixation methods.
■ Plateaus and hilly areas. Check shadows for each house
The same document states that the northern part of the city is the Miyata Plateau, while the central part is the Hikihashi Hills (approximately 80m above sea level). The locations of homes vary widely, including plateaus, hilly areas, and coastal areas, and the shadows cast by surrounding buildings, trees, and elevation differences differ for each house.
At Kakeru Koumuten, we create layout diagrams based on blueprints and the actual site conditions, allowing you to confirm through power generation simulations.
■ Average annual temperature of 16.2℃, annual precipitation of about 1,000 to 2,000mm
According to the city’s official documents, the average annual temperature in Miura City is 16.2℃, with a climate that is warm in winter and does not rise much in summer. The annual precipitation is about 1,000 to 2,000mm. Since there are periods of heavy rain, it is important to ensure waterproofing at the fixation points when installing on the roof.
■ City subsidies are on a first-come, first-served basis. Applications must be made before starting
Miura City’s priority measures acceleration project subsidy (official city) will be accepted on a first-come, first-served basis from May 1, 2026, to January 15, 2027, and will end once the budget is reached. Generally, pre-starting before the city’s grant decision is not allowed, so it is important to confirm the timing of the construction and the order of application before signing the contract.
■ Check the roof condition according to the age of the building
For homes that have been built for several years, it is important to check the condition of the roofing material and substrate before installing solar panels. Depending on the condition of the roof, installing them simultaneously with roof renovations can reduce future costs for removing and reattaching solar panels.
■ Be aware of dirt from sea winds, salt, sand dust, and fallen leaves
If sand dust or fallen leaves accumulate on the roof, it may affect power generation. Kakeru Koumuten can also handle solar panel cleaning with specialized brushes and rain gutter cleaning.
Our company is based in Kanagawa Prefecture and handles many exterior construction and solar projects in Miura City.
We are happy to assist with partial roof repairs such as roof overlay work, roof replacement, and leak repairs, as well as other repairs! Please feel free to consult us for any urgent issues!
Service Area in Miura City, Kanagawa Prefecture
Kakeru Koumuten accepts requests throughout Kanagawa Prefecture and all of Tokyo.
List of Areas in Miura City, Kanagawa Prefecture
Onoe Town, Miura City / Kaigai Town, Miura City / Misakiyou Town, Miura City / Sakae Town, Miura City / Shiraishi Town, Miura City / Shiroyama Town, Miura City / Suwa Town, Miura City / Tenjin Town, Miura City / Irie, Hatsuose Town, Miura City / Kouenbo, Hatsuose Town, Miura City / Shimomiya, Hatsuose Town, Miura City / Mito, Hatsuose Town, Miura City / Wada, Hatsuose Town, Miura City / Hara Town, Miura City / Harumi Town, Miura City / Higashioka Town, Miura City / Misaki, Miura City / Koajiro, Misaki Town, Miura City / Jogashima, Misaki Town, Miura City / Rokugai, Misaki Town, Miura City / Moriso, Misaki Town, Miura City / Kaneda, Minamishitaura Town, Miura City / Kamimiyata, Minamishitaura Town, Miura City / Kikuna, Minamishitaura Town, Miura City / Bishamon, Minamishitaura Town, Miura City / Matsuwa, Minamishitaura Town, Miura City / Miyakawa Town, Miura City / Mukougasaki Town, Miura City
・Please leave the exterior wall painting in Miura City, Kanagawa Prefecture to Kakeru Koumuten!
・Please leave the roof renovation in Miura City, Kanagawa Prefecture to Kakeru Koumuten!
・Please leave the exterior renovation in Miura City, Kanagawa Prefecture to Kakeru Koumuten!
・Kakeru Koumuten Co., Ltd. construction achievements
・Kakeru Koumuten Co., Ltd. after maintenance
・Kakeru Koumuten Co., Ltd. construction menu and price list
・Kakeru Koumuten Co., Ltd. staff blog and announcements
・Explaining the importance of comparative estimates and key points!
・12 major manufacturers of solar power generation! Features and selection points are also introduced!
・What are the installation costs for solar power generation? Thorough explanation of tips to reduce costs!
・What are the suitable locations for installing solar power generation? Key points for site selection are also introduced!
・Here is the introduction to solar power generation estimates!
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contact Kakeru Koumuten Co., Ltd.
Kakeru Koumuten is a young company whose team is, on average, in their late twenties, but our skills are second to none.
Our greatest strength is that we handle scaffolding, roofing and painting entirely in-house. In an industry where these tasks are usually divided among contractors, our complete service simplifies project management and helps keep costs down. Above all, if a problem arises, we respond promptly.
We proudly describe ourselves as the youngest and most helpful renovation company in Kanagawa!
