We conduct comprehensive technical reviews for wind and solar energy projects, ensuring compliance with regulatory standards, verifying energy production forecasts, and assessing operational reliability. Our evaluations cover site conditions, equipment performance, contracts, and construction progress, providing investors with confidence, minimizing risk, and enhancing long-term project bankability.
Wind Power Plants
A comprehensive technical due diligence forms the foundation of lenders’ and investors’ confidence in the value of a wind farm project. Our audit process not only verifies the technical foundation and financial sustainability but also guarantees compliance with all legal and regulatory standards.We validate the results of energy yield estimates and subject the operational safety of the turbines and the entire infrastructure to a critical review.We technically evaluate the robustness of contract terms for installation and operation and ensure that the overall concept complies with the highest industry standards. This comprehensive process significantly reduces investment risks, sharpens financial modeling, and sustainably increases the bankability of the project. Thus, we document the investment’s ability to achieve permanently reliable performance and attractive returns. We have summarized our detailed scope of services below.
Inspection of the current status of the facility, compliance with legal regulations, and readiness of the electrical infrastructure
It provides a comprehensive overview of the physical environment of the project, compliance with legal regulations, and the status of the electrical infrastructure. The analysis begins with the site plan and detailed terrain analyses, including the review of approved land maps, zoning plans, land acquisition documents, and construction permits. Subsequently, all grid-related matters are evaluated. This includes grid connection and grid usage agreements, single-line diagrams for high, medium, and low voltage networks, and the suitability of existing switchgear installations and overhead line capacities for future expansions. Additionally, key electrical studies such as short-circuit, cable, and protection relay calculations are summarized, along with assessments regarding land acquisition and hybrid capacity increases.
Furthermore, operational security measures such as the evaluation of the existing camera system, protocols for shared road usage with neighboring wind farms, and current agreements with the grid operator are also addressed. Finally, this section covers environmental and legal obligations through the requirements of forest authorities, including the review of ecosystem reports, fire-fighting resources, and special monitoring systems.
Standards: IEC 61936-1:2021, IEC 61400-25 series, ENTSO-E Network Code Requirements for Generators (RfG), IEEE 1547, ISO 45001:2018, IEC 61936-1, ISO 14001:2015, IEC 61400-1:2019, IFC Environmental, Health and Safety Guidelines for Wind Energy, ISO 9001:2015, IEC 61400-22
Evaluation of existing wind potential and energy yield calculations
The wind potential and energy yield of your project are decisive factors for the profitability of the wind farm. Our long-standing experience in wind potential and yield calculations forms the basis for the evaluation of third-party calculations. From various existing reports, we determine the most reliable energy yield and the lowest possible uncertainties for you.
Standards: IEC 61400-1:2019, IEC 61400-12-5:2022, IEC 61400-26-1:2019, IEC 61400-12-4:2020, FGW TG6, MEASNET: Evaluation of Site-Specific Wind Conditions v3, IEC 61400-15-1, ISO/IEC Guide 98-3:2008
Inspection of turbine conditions at operating facilities
Our analysis evaluates the technical and contractual operational robustness, reliability, and maintainability of the wind farm. We subject turbine supply agreements (TSA), service agreements (O&M), maintenance protocols, and OEM reports to a detailed review. The objective is to ensure that daily operations are in compliance with contractual guarantees and international best practices.
In addition, we verify the long-term integrity of the facility through component inspections, bonus-malus calculations, and spare parts strategies. The infrastructure, ranging from switchgear compatibility to technical upgrades, is also evaluated for future expansions. The Due Diligence process is completed with a safety and risk assessment: we check the condition of the rotor blades, lightning protection, and fire protection systems, as well as the SCADA connection and data integrity. Thus, we determine whether risk mitigation measures guarantee permanent and reliable performance.
Standards: ISO 20816-21:2025, ISO/DIS 16079-1, IEC 61400-26-1, IEC 61400-12 series, FGW TG2, FGW TG6, MEASNET Procedure v5
Review of turbine supply, operation, and maintenance contracts
We analyze Turbine Supply Agreements (TSA) and Operation and Maintenance (O&M) contracts by reviewing their durations, guarantee structures, and liability clauses in detail. The verification of performance guarantees and termination rights according to current industry standards ensures the high expectations of investors and lenders are met.
Specifically, we focus on the robustness of bonus-malus arrangements within the active EPC framework and the applicability of long-term service obligations. In this process, we evaluate the clarity and comprehensibility of escalation formulas, extension options, spare parts management, and response times. Our objective is to ensure a balanced distribution of risk between the OEM and the operator, appropriately protecting the long-term operational integrity of the project.
Standards: ISO 10845-1, FIDIC Contracts
Review of your wind farm’s specifications and design data
We provide a detailed analysis of the technical specifications and design features of your wind turbines. The assessment is based on project-specific documentation and other relevant technical documents.
The primary objective is to evaluate the documented compliance of the turbine’s main components with internationally recognized standards, particularly the IEC 61400 series and related EN and ISO standards. Our review summarizes the technical specifications, evaluates evidence of conformity obtained from available documents (type certificates, MTCs, inspection reports, type test summaries), and identifies any significant documentation deficiencies that prevent a complete review.
Standards: IEC 61400-1, IEC 61400-4, IEC 61400-5, IEC 61400-6, IEC 61400-24, IEC 61400-25
It is important for both investors and financial institutions to ensure the reliability of the financial model by confirming that project cost estimates are realistic and in line with market conditions, and to guarantee timely and budget-compliant delivery for financial closure and commercial operation by providing lenders with transparent, timely reporting on project implementation.
The financial health and physical progress of the wind energy project are monitored and verified throughout the project lifecycle. The project’s time and budget status is reported independently to lenders and investors.
The service includes verification of the CAPEX and OPEX assumptions used in the financial model (broken down by main packages such as turbines, BOP, electricity, infrastructure, etc.). These costs are compared with reference costs from recent similar projects to assess whether they are reasonable. Contingency levels, escalation assumptions and currency risk exposure are also reviewed. Additionally, main supplier offers and payment schedules are verified.
During the construction phase, physical progress is independently monitored against the project schedule and budget. Milestone completion certificates are verified prior to credit payments. Construction quality, major equipment deliveries, and commissioning progress are reviewed. Monthly reporting is conducted on completion costs, programme deviations, and risk items affecting the commercial operation date (COD).
Standards: IFC Performance Standards & EHS Guidelines (General + Wind Energy), FIDIC Conditions of Contract (Red/Yellow/Silver Book), IEC 62446-1, IEC 62446-2, EN 1991, EN 1993, EN 1997
A comprehensive technical review ensures that a solar energy project is technically sound and financially viable. It verifies legal compliance, energy production forecasts, and operational reliability, while assessing procurement, O&M agreements, and design standards, reducing investment risk and strengthening project bankability.The scope of the work is summarised below.
A comprehensive overview of the project’s physical conditions, legal compliance, and electrical infrastructure readiness is provided. This section begins with site layout and terrain slope, reviewing all approved base maps, zoning plans, land acquisition files, and construction permits. It then addresses grid connection and usage agreements, single-line diagrams for HV, MV, and LV grids, and the suitability of existing HV/MV equipment and overhead line capacity for potential expansions. Supporting electrical works such as short-circuit, cable, switchgear and protection relay calculations are summarised, and potential additions are evaluated in terms of land acquisition and hybrid capacity increase. Operational security is addressed through the status of the existing security camera system, perimeter fencing and access routes, as well as potential overhead line contracts with the system operator. Finally, environmental and legal constraints are identified by reviewing ecosystem assessment reports and environmental authority requirements, including firefighting resources and special monitoring systems.
Standards: IEC 61936-1:2021, ENTSO-E Network Code Requirements for Generators (RfG), IEEE 1547, ISO 45001:2018, IEC 61936-1, ISO 14001:2015, IEC 62548, IEC 61215-1, IFC EHS Guidelines for Solar Power Projects, IEC 62446-1, IEC 61730
The solar resource of the site and the annual energy production of the solar power plant are evaluated. The analysis is based on solar radiation data obtained from measurement stations, satellite-based irradiance datasets, and simulation software such as PVsyst; these datasets undergo rigorous quality control and are restructured to form a reliable analytical basis. Using verified data, actual production values are compared with simulation results, and losses are quantified. Furthermore, strategic upgrade alternatives such as hybrid wind integration, capacity increases, or panel replacement (repowering) options are examined to project energy production for future configurations and evaluate the long-term performance of the existing facility.
Standards: ISO/IEC Guide 98-3:2008, IEC 62548, IEC 61215-1, IEC 61724-1:2021, IEC 61724-3, IEC 62446-1:2023, IEC 61853 Series
Verification of the operational robustness, reliability and sustainable maintenance capability of the PV system from both a contractual and technical perspective. Where available, the study examines panel and inverter supply contracts, maintenance contracts, performance review files, fault records, maintenance reports, measurement and SCADA data, and manufacturer service reports to assess the extent to which daily operations comply with contractual guarantees and industry best practices. Furthermore, evidence of equipment replacements, indemnity or premium payments, substation and switchgear compatibility, spare parts strategies, and previous technical improvements are addressed to analyse long-term asset integrity and readiness for expansion. Organisational roles, access controls, audit findings, panel surface condition surveys, fire safety systems with SCADA connection, and historical data storage practices are also evaluated to determine the adequacy of existing risk mitigation and monitoring measures for continuous, reliable performance.
Standards: IEC 62941, IEC 61215-2, IEC 61724-1, IEC 61724-2, IEC 61724-3, IEC 61853-1/-2, IEC 61853-3/-4, IEC 62670-1, IEC 62738
Panel, Inverter and Carrier System Supply, Operation and Maintenance Contracts are examined in detail in terms of validity period, warranty provisions, liability exemptions, performance guarantees and termination clauses. This review covers issues such as the adequacy of the warranty scope and duration, the clarity of liability exemptions, the robustness of penalty clauses and premium mechanisms defined based on production and performance. In particular, the feasibility of long-term service commitments under existing contracts is assessed in detail, taking into account renewal options, price increase formulas and termination rights. Furthermore, the extent to which obligations relating to spare parts management, response times, and reporting protocols are clearly defined, and whether the risk distribution between the manufacturer and the operator sufficiently protects the long-term operational integrity of the project, are also examined.
Standards: ISO 10845-1, FIDIC Contracts
An examination of the characteristics and design information of the solar power plant equipment (panels, inverters, transformer station and auxiliary equipment) is presented. The assessment is based on project-specific documentation and other relevant technical files.
The primary objective is to assess the documented suitability of the equipment against solar energy-focused international standards, primarily IEC 61215, IEC 61730, IEC 62109, and related EN and ISO standards. The review summarises the technical specifications, evaluates the evidence of compliance from the available documentation (Type Certificates, test reports, quality certificates, factory inspection reports) and identifies significant documentation gaps that prevent full validation.
Standards: IEC 62548, IEC 62109-1/-2, IEC 61215-1/-2, EN 1991 / EN 1993 / EN 1999 (Eurocodes), IEC 62817, IEC 62305, IEC 61643-32, IEC 61850-7-420
It is important for both investors and financial institutions to ensure the reliability of the financial model by confirming that project cost estimates are realistic and in line with market conditions, and to guarantee timely and budget-compliant delivery for financial closure and commercial operation by providing lenders with transparent, timely reporting on project implementation.
Both the financial health and physical progress of the solar energy project are monitored and verified throughout the project life cycle. The project’s time and budget status is reported independently to lenders and investors.
The service includes verification of the CAPEX and OPEX assumptions used in the financial model (broken down by main packages such as panels, inverters, BOP, electricity, infrastructure, etc.). These costs are compared with reference costs from recent similar projects to assess whether they are reasonable. Contingency levels, escalation assumptions, and currency risk exposure are also reviewed. In addition, main supplier offers and payment schedules are verified.
During the construction phase, physical progress is independently monitored against the project schedule and budget. Milestone completion certificates are verified prior to credit payments. Construction quality, major equipment deliveries and commissioning progress are reviewed. Monthly reporting is conducted on completion costs, programme deviations and risk items affecting the commercial operation date (COD).
Standards: IFC Performance Standards & EHS Guidelines (General + Solar Energy), FIDIC Conditions of Contract (Red/Yellow Book), IEC 62446-1, IEC 62446-2, EN 1990, EN 1991