Studsvik AB: Studsvik and ReNu Industries partner to bring inDRUM waste treatment technology to Fukushima

23 October 2026, Nyköping, Sweden - Under the agreement, Studsvik will provide ReNu with technical information and advice on design conditions for a Japanese version of inDRUM. ReNu will design a pilot plant adapted to Japan's seismic and regulatory requirements and to the characteristics of the waste to be treated.

The partnership is the first step in the model Studsvik has chosen for taking inDRUM to international markets. Studsvik will build and operate its own inDRUM facilities in Sweden, while abroad it will license the technology and work with local partners that design, build and operate the plants.

inDRUM, developed and patented by Studsvik, treats radioactive waste inside sealed drums. Each drum is placed in a treatment unit and heated under a nitrogen blanket, which removes free liquids, breaks down organic material and leaves a stable residue suitable for long-term storage and disposal. Because the drums are neither opened nor sorted, worker exposure and manual handling are minimised. For spent ion-exchange resins and similar wastes, volume can be reduced by up to 90 per cent. Studsvik operates a full-scale inDRUM demonstration facility in Nyköping and is advancing the adoption of inDRUM for the treatment of radioactive waste from the European Spallation Source (ESS) in Lund.

Decommissioning of the Fukushima Daiichi Nuclear Power Plant is expected to take 30-40 years, and the decommissioning of other nuclear power plants in Japan is gathering pace. At the same time, Japan is restarting reactors shut down after 2011, which increases the need for waste treatment and for other services Studsvik provides. Reducing and stabilising the volume of radioactive waste is a long-term challenge in this work.

ReNu has been awarded up to JPY 700 million (approximately USD 4.4 million) under the Subsidy for Projects Promoting Practical Development for Regional Reconstruction, implemented by Fukushima Prefecture under the Japanese Government's Fukushima reconstruction initiative, to develop a radioactive waste treatment pilot plant in Fukushima. ReNu aims to establish the basic design conditions for the Japanese version of inDRUM during fiscal year 2026, which ends in March 2027, and, subject to the necessary agreements, to complete the pilot plant in fiscal year 2028.

Building on the Fukushima project, Studsvik and ReNu will explore deploying inDRUM elsewhere in Japan and in Asia, as well as broader cooperation in nuclear engineering, including fusion.

"Fukushima will need radioactive waste treatment for decades. ReNu is based in Okuma, the town that hosts the plant, and brings the local knowledge needed to adapt inDRUM to Japanese conditions. Fukushima is our starting point in Japan and in Asia," says Karl Thedéen, President and CEO, Studsvik.

"Studsvik Japan will coordinate the Studsvik Group's experts and support ReNu as it develops the Japanese version of inDRUM," says Masatoshi Yamasaki, President and Representative Director, Studsvik Japan.

"Decommissioning Fukushima requires technology proven around the world, re-engineered to fit Japan's regulations and site conditions and implemented with local hands. Through our technical collaboration with Studsvik, ReNu will adapt inDRUM to Japanese regulatory and site requirements. We intend to build on our experience in Fukushima to pursue opportunities elsewhere in Japan and overseas," says Ryohei Takahashi, CEO, ReNu Industries Inc.

The agreement is not expected to have a financial impact of such materiality that it significantly affects Studsvik Group's results during 2026-2027.

For more information, please contact:

Studsvik AB, Media Relations: media.relations@studsvik.com

ReNu Industries Inc., Public Relations: info@renu-industries.com

About Studsvik

Studsvik is an independent nuclear technology company active across the full nuclear lifecycle, from new build development to existing fleet services, operations support and decommissioning. It is a leading supplier of vendor-independent reactor analysis software, and its hot cell laboratories in Nyköping test fuel and materials for fission and fusion applications worldwide. Studsvik also provides radiation protection services and technology for treating radioactive waste, and handles and packages radioisotopes for healthcare and industry. ReFirm is Studsvik's platform for new nuclear development in Sweden. Founded in 1947 as the centre of Sweden's national nuclear programme, Studsvik today serves operators, fuel vendors, technology developers and regulators in more than 20 countries, has approximately 540 employees in six countries, and is listed on Nasdaq Stockholm (SVIK).

www.studsvik.com  https://www.linkedin.com/company/studsvik/

About ReNu Industries

ReNu Industries Inc. is a nuclear engineering start-up founded in December 2025 and headquartered in Okuma Town, Futaba District, Fukushima Prefecture, Japan. Through the business succession of local nuclear suppliers and the introduction of advanced technologies from overseas partners and universities, ReNu works to rebuild the nuclear supply chain and accelerate decommissioning. ReNu has raised seed funding from leading Japanese venture capital firms including Spiral Capital, Miraisozo Investments, Mitsubishi UFJ Capital, Fukui Capital Partners and Joyo Capital Partners.