Global Wind Energy Certification Services

Combining technical expertise with many years of in-depth industry experience, DEWI-OCC (a UL company) offers global, one-stop wind energy certification services to turbine manufacturers, component manufacturers, project developers, utilities and other companies within the sector.

DEWI-OCC belong to the UL family of companies. 

DEWI DEWI-OCC UL (Underwriters Laboratories) National & International Committees DEWI Accreditations Quality Agreements


Recognised worldwide as a leading independent certification body of on-/offshore wind turbines and their components.


A premier global independent safety and performance science company, with nearly 120 years of history.

National & International Committees

The DEWI Group is recognised by national and international committees as a key participant in defining wind energy standards, such as:

  • IEC – International Electrotechnical Commission
  • IEA – International Energy Agency
  • CENELEC – Comité Européen de Normalisation Électrotechnique
  • DKE – Deutsche Kommission Elektrotechnik Elektronik-Informationstechnik in DIN und VDE
  • Technical Guidelines for Wind Turbines (guidelines published by FGW, Germany)
  • DPInst – Committee of German Certification Bodies for Wind Turbines

DEWI Accreditations

The accreditations are valid for the DEWI locations, test and calibration procedures mentioned in the certificates. The certificates are available on request or at Opens external link in new
DEWI-OCC is financially funded by the fees charged to its clients for the certification services provided. Fees are charged for the evaluation and certification processes as well as for ongoing surveillance. Annual fees may also be charged, where applicable. These fees are provided on quotations.