As the first event in this biennial series, CleanTech2025 will focus on Hydrogen Energy and Photovoltaic Technologies, bringing together leading researchers, industry professionals, and policymakers to discuss advancements and innovations in clean energy solutions. Essential Guidelines for Abstract Submission Language Quality: All abstracts must be written in English and carefully proofread for grammar and clarity. Author Registration Requirement: To ensure commitment and prevent no-shows, at least one author must complete full registration before uploading the full-text of the paper. Presentation Limits: Each presenting author is allowed to present up to two abstracts per registration. Final Submission Policy: Once the submission deadline has passed, no further edits or replacements will be allowed. Please review your submission carefully before finalizing it. Types of Presentation Abstracts may be submitted for oral or poster presentations. The Scientific Committee will review all submissions and make the final decision on the presentation format, taking the author's preference into consideration. Please Note: The Scientific Committee may change the presentation type during the evaluation process based on the content and program requirements. Topics for Abstracts During the abstract submission process, authors must select the most relevant topic for their abstract. Notification The abstract submission system will close after the deadline, and no further submissions will be accepted. Once the submission period ends, all abstracts will be evaluated by a panel of referees. Authors will receive a notification of acceptance via email, including information on the presentation format (oral/poster). Proceedings The proceedings of the CleanTech2025 will be published under Clean Energy Technologies Journal, which is indexed in IdealOnline, Asian Science Citation Index, Open Ukrainian Citation Index, Scilit and Gale Cengage.