TÜV Rheinland Japan provides expert insights on Technical Due Diligence (TDD) for solar power plants and Battery Energy Storage Systems (BESS). This edition focuses on lender-oriented TDD for BESS projects.

ESS Market Expansion and Opportunities
Energy Storage Systems (ESS), including Battery Energy Storage Systems (BESS), are increasingly deployed worldwide to balance electricity supply and stabilize the grid. As renewable energy adoption grows, ESS are also helping support grid stability and provide energy flexibility. In Japan, capacity and demand adjustment markets are rapidly developing, creating opportunities for diverse business models, including aggregation services.
Comprehensive Technical Due Diligence for BESS Projects
Since the launch of our TDD services for BESS, TÜV Rheinland Japan has supported numerous projects. We continuously expand and tailor our services to meet project-specific needs.
Current key evaluation areas include:
- Site assessment and on-site inspection
- Noise evaluation (Using CadnaA acoustic simulation)
- Project design and Technology review
- Contract review (EPC, O&M, PPA, and long-term ESS service agreements etc)
- Required permits and approvals review
- Aggregator assessment, Aggregator contract review
- Project cost and financial model review
- Construction monitoring
- Site Acceptance Test (SAT) witness and test result evaluation
TDD reports for lenders can also include flexible evaluation items tailored to specific project needs. Please feel free to contact us for any scope not listed above.
TÜV Rheinland Japan’s Expertise in BESS and Solar Projects
With extensive experience in TDD across planning, construction, and operation of solar power plants, TÜV Rheinland Japan is a trusted partner for financial institutions and investors worldwide.
In addition, our team includes engineers with practical experience in BESS development, enabling us to provide comprehensive and reliable technical assessments for BESS projects.
Since the launch of this service, we have supported projects from early planning stages through construction. Our track record includes BESS TDD assignments not only with developers in Japan but also with investment companies in China and lenders in Korea.
For more information on Technical Due Diligence for Lenders and/or to discuss specific projects, please contact us:
Customer Service: TEL: +81-45-470-1850 | E-Mail: info@jpn.tuv.com

