Osaka Metro Gearing Up for Clean Transportation with Panasonic Hydrogen Energy and Solar Power Technology

Osaka is Japan’s second largest city. Osaka Metro Co., Ltd. (Osaka Metro) functions like arteries in this dynamic international metropolis. Osaka Metro not only operates an extensive rail network in the region, but it also plays a pivotal role in urban development and community initiatives, helping shape the future of Osaka.

Osaka Metro positions itself as a transportation-focused community development enterprise that supports Osaka’s urban fabric. The company is now tackling carbon neutrality as its next challenge.

In October 2024, Osaka Metro began a demonstration test on a high-voltage grid system for transmitting integrated electricity from solar and hydrogen power generation to be used in its operations. The test is being conducted at the Morinomiya Inspection Yard with the aim of expanding Osaka Metro’s use of renewable energy. Panasonic Corporation’s Electric Works Company (Electric Works) has developed and supplied the systems for the demonstration test. We are pleased to introduce the details of the test and systems that illuminate the path toward a decarbonized society. 

Osaka Metro has announced its goal to achieve carbon neutrality by fiscal year 2050, setting an ambitious target for the entire group to reduce CO₂ emissions by 46% (compared to 2013 levels) by 2030. To reduce electricity consumption, the company is implementing energy-saving initiatives that include the introduction of energy-efficient vehicles and the transition to LED lighting in station facilities.

Since the majority of CO₂ emissions from its business activities come from the use of electricity, Osaka Metro determined that utilization of renewable energy for power generation would be an essential addition to its current energy-saving measures. After exploring various approaches to address the challenge, Osaka Metro selected Panasonic as its contractor, adopting an energy solution that combines electricity from hydrogen fuel cells with electricity generated from solar power.

Osaka Metro has announced that it will expand the use of renewable energy in its own facilities as part of its mission. While gathering information from various manufacturers, people at Osaka Metro were particularly impressed by “Panasonic HX Kusatsu,” a demonstration facility at Panasonic’s Kusatsu Plant.

Panasonic HX Kusatsu demonstrates a power generation system that uses renewable energy to supply 100% of the electricity for Panasonic’s fuel cell factory in Kusatsu, Shiga Prefecture.* The facility began operation in April 2022.

*While the hydrogen used at the start of the Panasonic HX Kusatsu demonstration project was not produced from renewable sources, the plan is to achieve RE100 (Renewable Energy 100%) status by switching to hydrogen from renewable sources in the future.

In January 2023, representatives from Osaka Metro inspected the Kusatsu Plant and decided that the system implemented there, which combines the use of proprietary pure hydrogen fuel cell generators, solar power generation, and storage batteries, is closely aligned with the vision of Osaka Metro. Following the inspection, Electric Works proposed a plan to “combine electricity generated from solar and hydrogen power generation to be transmitted at high voltage.” Osaka Metro concluded that this was an effective plan to increase renewable energy usage as it leverages existing railway infrastructure. Consequently, the company decided to introduce this system and began a demonstration test.

Osaka Metro’s first challenge was to introduce equipment for hydrogen power generation in its facilities. Before implementation, the company developed a clear consensus among all the relevant internal and external stakeholders to ensure full understanding of the specifications and requirements for the planned equipment and systems, including the solar power generation systems, as well as their potential impact on safety and the quality of electricity produced.

Panasonic installed a high-voltage interconnect system for hydrogen and solar power generation at the Morinomiya Inspection Yard. This system integrates 100 kW from solar power with 10 kW from pure hydrogen fuel cell generators. It delivers a combined output of 110 kW, supplying electricity to the yard’s power substation. The system is configured with dedicated control and measurement systems to monitor power generation and the operational condition of equipment.

The new system supplied power during e METRO MOBILITY TOWN, the future mobility experience theme park held in the Morinomiya district for local residents to experience Osaka Metro’s vision for the future of transportation and daily life.

Installation of the system was completed in September 2024. The demonstration test began the following month in October and will be completed by the end of March 2026.

“Through this initiative, we aim to learn more about the stability of power supplied from multiple renewable energy sources so that we can utilize renewable energy sources to power our railways in the future,” said Shun Nohzuka from the Advanced Technology Center in Osaka Metro’s Transportation Business Division.

The Panasonic Group is advancing its initiatives to achieve carbon neutrality and a circular economy as a part of its long-term environmental vision, “Panasonic GREEN IMPACT.” One of the key technologies driving these efforts is the fuel cell, which the company has been developing since 1999.

The pure hydrogen fuel cell generator “PH1+” delivered to Osaka Metro was an industrial application of the technology developed for “Ene-Farm,” a residential fuel cell. Highly efficient for power generation and reliable, PH1+ can be configured flexibly to create systems that are tailored to meet customer needs.

Electric Works supported Osaka Metro with technological expertise as a Panasonic group company. As a new initiative, Electric Works took on the challenge of developing a dedicated rack unit configuration for hydrogen fuel cell systems.

In this configuration, the rack unit for the system was pre-assembled at the factory in an easily transportable size. Pure hydrogen fuel cell generators, a cooling tower for waste heat treatment, a hydrogen leak alarm panel, and a lighting power panel were installed on the rack.

This modular mounting configuration saves space and simplifies installation. Installation work, often affected by weather and typically taking around 30 days, was completed in around 10 days—about a 70% reduction in construction time.

Furthermore, Electric Works proposed a demonstration test using a proof-of-concept monitoring system, combining the use of “Solanet” for monitoring solar power and other power generation equipment along with the use of “P·TEM” for energy visualization. The monitoring system sends data from the control and measurement systems to Solanet and P·TEM using dedicated lines.

The system facilitates remote monitoring of e METRO MOBILITY TOWN from Osaka Metro headquarters, providing the company with clear visualization of energy availability and usage status.

Masaru Hikosaka from Electric Works’ Solution Engineering Division supported system construction at the Morinomiya Inspection Yard. He explained, “Our proof-of-concept monitoring system allows for the safe operation of pure hydrogen fuel cell generators.” He also added, “This marks our first venture into hydrogen-related monitoring solutions. We appreciate the valuable opportunity to take on this challenge.”

Through this project, Nohzuka from Osaka Metro and Hikosaka from Panasonic each renewed their commitment to realizing a decarbonized society for their companies. Nohzuka elaborated, saying “The railway business consumes enormous amounts of electricity to operate hundreds of trains every day as scheduled. As a company involved in Osaka’s urban development, we believe that we can reduce environmental impact not only in railways but also in non-railway areas, like bus services, by implementing renewable energy initiatives in our operations. In this way, we hope to contribute in addressing environmental issues for society.”

Reflecting on his own experience as an engineer, Hikosaka remarked, “For nearly 30 years, I’ve been involved in developing solar cell modules for Panasonic. When I first joined, solar cells were mainly used in calculators.” He is also seeing a bright future for fuel cell technology, saying, “fuel cells are still new as products, but I am confident that they will connect us to the future, just as solar cells have gained worldwide recognition over the past 30 years.”

“This time, we were able to provide a solution utilizing our cutting-edge technology for Osaka Metro. This project will undoubtedly become a cornerstone supporting the future of railway infrastructure. I am really pleased about that,” Hikosaka concluded.

Panasonic has launched hydrogen energy projects not only at its Kusatsu Plant but also in Cardiff, Wales in the U.K. and in Munich, Germany. Building on the experience gained from successfully supporting Osaka Metro, Panasonic will continue to contribute to the realization of a carbon-neutral society worldwide by expanding its services globally.