Electricity Prices Up ~53% Since 2010: iChoosr Explains HEMS from Basics to Benefits

iChoosr Ltd. (Headquarters: Minato-ku, Tokyo; President & CEO: Akira Hirose; hereinafter “iChoosr”) operates the group purchase program for solar panels and home batteries, “Taiyō no Mirai ni Taiyō Kō,” currently active in 24 prefectures across Japan.

According to the Agency for Natural Resources and Energy, the average household electricity price in fiscal 2024 has risen approximately 53% compared to fiscal 2010. Against the backdrop of rising fuel prices and global instability, energy costs continue to climb. Efficient use of limited energy resources and reducing household electricity expenses have become critical challenges. Additionally, as the FIT (Feed-in Tariff) system undergoes annual price reductions and policy revisions, the shift from “selling” surplus electricity to “self-consumption” is accelerating.

In this context, the adoption of HEMS (Home Energy Management System) is gaining attention as a way to more effectively utilize solar panels and home batteries. HEMS is a system that visualizes household energy consumption and efficiently manages and controls home appliances and electrical equipment.

This time, Kazunori Nishihara, Senior Project Manager at iChoosr, explains the fundamental mechanisms and roles of HEMS, along with the benefits expected from its adoption.

※This image was created using generative AI

Summary of this newsletter

- HEMS is a system that optimizes household energy use

- Contributes to reducing household electricity costs through integration with solar panels, batteries, and EVs

- Enhances resilience during disasters

- Government and local government subsidy programs may be available for HEMS adoption

※1 Agency for Natural Resources and Energy, METI, “Japan’s Energy 2025” – “10 Questions to Understand Energy Today,” 3. Economic Efficiency

https://www.enecho.meti.go.jp/about/pamphlet/energy2025/03.html

※2 Agency for Natural Resources and Energy, METI, Feed-in Tariff Rates and Periods (From FY2026 Onward)

https://www.enecho.meti.go.jp/category/saving_and_new/saiene/kaitori/fit_kakaku.html

What is HEMS? – A Home Energy Optimization System

HEMS (Home Energy Management System) visualizes household energy usage in real time and automatically optimizes the control of home appliances and electrical systems. Not only can household power consumption be monitored via smartphones or display screens, but HEMS also integrates multiple devices—such as solar power systems, home batteries, air conditioners, EcoCute water heaters, and electric vehicles—to reduce energy waste.

Smart meters installed by power companies primarily measure and transmit electricity usage. In contrast, HEMS functions as an energy management system that connects with various household devices, enabling energy visualization, automatic control, and optimal operation.

HEMS adoption is progressing mainly in new homes. As of 2023, 12.7% of homes built since 2021 have adopted HEMS. However, the overall adoption rate across all homes remains at just 2.7%.※3 Key barriers include the initial installation cost and the need to verify compatibility with existing appliances and home systems. Additionally, the benefits of HEMS vary by household electricity usage, so it is recommended to explore government and local subsidy programs when considering adoption.

※3 Ministry of the Environment, FY2023 Household CO2 Emissions Survey Report (Final Data), pp. 97–98

https://www.env.go.jp/content/000323423.pdf

Integration with Solar Panels, Batteries, and EVs is Key

HEMS maximizes its effectiveness when integrated with renewable energy systems such as solar panels and home batteries. By linking with solar panels and batteries, HEMS increases self-consumption rates and contributes to reducing household electricity costs, even as buyback prices continue to decline.※2 ※4 When combined with batteries, HEMS can automatically charge during off-peak hours for daytime use, or store surplus solar power for use in the evening, thereby optimizing generation, charging, and discharging.

Moreover, during emergencies such as power outages, HEMS enables efficient use of stored battery power and solar-generated electricity, making it easier to secure essential household power and enhancing resilience from a disaster preparedness perspective. Thus, HEMS is expected to serve as an energy management system that supports not only efficient energy use and electricity cost reduction but also emergency power supply.

When adopting HEMS, it may be possible to utilize subsidy programs offered by national or local governments. Since the details—such as eligibility, target equipment, subsidy amounts, and application periods—vary by year and municipality, it is recommended to check with your local government and the latest subsidy programs before proceeding.

※4 Agency for Natural Resources and Energy, METI, Feed-in Tariff Rates and Periods (2012–2025)

https://www.enecho.meti.go.jp/category/saving_and_new/saiene/kaitori/kakaku.html

Profile of the Commentator

Kazunori Nishihara

Senior Project Manager / New Business Development, iChoosr Ltd.

August 2024: Joined Huawei Japan’s Digital Power Business Unit, responsible for residential PCS and battery systems

Experienced in sales, alliance development with installers, and collaboration with domestic and international panel manufacturers

Currently promoting municipal partnerships and new business launches

About the “Taiyō no Mirai ni Taiyō Kō” Group Purchase Program

The group purchase program for solar panels and home batteries leverages economies of scale from high participation, enabling the adoption of renewable energy systems at fair and transparent prices. It significantly reduces the burden on consumers who would otherwise need to find installers individually, offering a trustworthy and equitable process that goes beyond simple bulk purchasing.

The program removes barriers to purchase—such as “can’t choose,” “can’t trust,” and “don’t understand”—caused by information overload and unfamiliarity with products, through “comprehensive support.”

Through rigorous screening and bidding, the program selects reliable sales and installation companies and products, offers clear warranties, and ensures fair pricing—providing a system that enables consumers to adopt renewable energy with confidence.

About iChoosr Ltd.

Founded in 2008, iChoosr Ltd. is headquartered in Amsterdam, the Netherlands, and operates services supporting the adoption of renewable energy in the Netherlands, Belgium, the UK, the US, and Japan.