Cosmo Eco Power and NSK Demonstrate Technology for Monitoring Lubrication Status of Wind Turbine Bearings in Actual Operating Environments

Cosmo Eco Power Co., Ltd. (Headquarters: Shinagawa-ku, Tokyo; President: Fumiaki Nokura; hereinafter "Cosmo Eco Power"), a group company of Cosmo Energy Holdings Co., Ltd. (Headquarters: Chuo-ku, Tokyo; President: Shigeru Yamada), and NSK Ltd. (Headquarters: Shinagawa-ku, Tokyo; Director, President and CEO: Toshikazu Nishisa; hereinafter "NSK") are promoting joint initiatives (hereinafter "the Initiatives") including multiple demonstration experiments aimed at the long-term stable operation of wind power generation equipment and the advancement of its operation and maintenance.

As part of these Initiatives, we are pleased to announce that we have conducted a demonstration experiment for the first time in an actual operating environment*1 using NSK's proprietary technology (hereinafter "the Technology") for monitoring the lubrication status of bearings for wind power generation equipment, confirming its applicability for practical use.

*1 NSK research as of June 2026

Image of New Condition Monitoring Method Features and Expected Effects

The Technology is expected to enable earlier detection of changes in bearing condition compared to conventional methods, contributing to improved reliability of wind power generation equipment and more efficient maintenance.

We will strengthen our efforts towards the practical application of this Technology going forward.

Through the Initiatives, both companies will provide new value to customers by leveraging the knowledge gained, and contribute to the stable supply of renewable energy and the realization of a carbon-neutral society.

1. Background of the Initiatives

Wind power is positioned as a primary energy source for renewable energy in Japan, and its introduction is expected to expand further. However, in addition to the increasing size of equipment and the diversification and harshness of installation environments, coupled with the impact of social conditions such as recent soaring material prices, wind power generation businesses are required to further improve their competitiveness.

In this business environment, operation and maintenance (hereinafter "O&M") after the start of operation is one of the areas that significantly impacts business viability. National technology strategies also indicate the necessity of O&M efficiency and advancement, and data-based rational operational decision-making as important elements supporting the sustained expansion of wind power generation.

For the efficiency and advancement of O&M, it is essential to properly grasp the condition of rolling bearings installed in wind power generation equipment, conduct continuous monitoring and diagnosis, and perform appropriate maintenance based on these findings. This is because rolling bearings are used in the gearboxes and main shafts of wind power generation equipment and are critical components supporting their operation. On the other hand, even with current preventive maintenance practices, there are many cases where decisions on repairs and parts replacement are made based on past examples and field experience when unexpected failures occur. Therefore, there was a demand for the advancement of mechanisms that objectively and quantitatively grasp the condition and risks of equipment, and improve the accuracy of decisions regarding continued operation and maintenance policies.

2. Overview and Future Development of the Initiatives

In response to these challenges, Cosmo Eco Power and NSK are working on demonstrating new O&M methods that contribute to ensuring long-term stable operation and high operating rates. As part of this effort, we have now conducted a demonstration experiment for the first time in an actual operating environment at a wind power generation facility operated by Cosmo Eco Power to monitor the lubrication status of bearings, confirming its applicability for practical use.

The Technology is a proprietary technology developed by NSK*2. We are verifying the practical application of this Technology by combining the field knowledge cultivated by Cosmo Eco Power through the operation and maintenance of wind power generation equipment with the condition monitoring and diagnostic technologies developed by NSK.

In the verification, we confirmed that changes in the lubrication status of bearings, which were difficult to detect with conventional condition monitoring, can be detected. This allows for consideration of maintenance measures at an earlier stage compared to conventional methods that estimate changes in bearing condition from vibrations, etc.

*2 This Technology was developed as an applied technology based on NSK's proprietary knowledge of lubrication status visualization. Please refer to the technical information for related fundamental technologies.

Both companies will continue to promote evaluation towards the practical application of this Technology, aiming to optimize the replacement cycle of lubricants used in equipment and improve the efficiency of equipment inspections and repairs. Furthermore, as a further development, we are also proceeding with verification of remaining useful life prediction technology to quantitatively assess changes in bearing condition as risks that could affect equipment operation.

By advancing these demonstration experiments, both companies aim to provide new value such as ensuring high operating rates for wind power generation equipment, reducing life cycle costs, and lowering environmental impact.

Image of New Value Created by Cosmo Eco Power and NSK

About Cosmo Eco Power

As a member of the Cosmo Energy Group, Cosmo Eco Power is engaged in the development and expansion of renewable energy, including wind power generation, towards the realization of "Carbon Net Zero by 2050." We will continue to strengthen cooperation with customers promoting decarbonization, and contribute to the promotion of renewable energy and the development of local communities.

About NSK

Since producing Japan's first bearings in 1916, NSK has supported the development of global industries by creating a variety of innovative products and technologies, including bearings, automotive components, and precision machinery products, for over 100 years. NSK expanded overseas in the early 1960s and now has bases in approximately 30 countries, leading the world in bearings as the third largest manufacturer, and also leading in ball screws and electric power steering, among other products.

For more details about NSK, please visit this page.

Reference Information

<Product Information>

・Condition Monitoring Solutions

<Technical Information>

・Lubrication Condition Monitoring of Deep Groove Ball Bearings Using the Electric Impedance Method (NSK Technical Journal, No. 696)

<Press Releases Related to Product Lifecycle Management (PLM)>

・March 2021 Completion of Acquisition of Condition Monitoring System Business

・January 2022 Expansion of Product Lifecycle Management (PLM) Strategy in the United States

・September 2023 Commencement of Development towards Practical Application of Condition Monitoring System for Linear Motion Products

・October 2024 Expansion of Condition Monitoring Solutions Supported by Equipment Diagnostic Experts

・March 2025 Development of High Load Capacity Large Tapered Roller Bearings Compatible with Reconditioning, an Industry First

・July 2025 Publication of Bearing CFP Calculation Report, an Industry First

・September 2025 Commencement of Verification of Initiatives to Promote Bearing Refurbishment and Reuse