The Ministry of New and Renewable Energy (MNRE) has issued revised guidelines for installation of prototype wind turbine models. The revised guidelines allow prototype wind turbines a maximum of three years to complete type testing and obtain certification from internationally accredited agencies. The guidelines form part of an updated framework for prototype wind turbine installations, to be implemented by the National Institute of Wind Energy (NIWE), Chennai. As per the draft, prototype models will be installed solely for the purpose of type testing. A recommendation letter from NIWE will be issued to initiate testing, and a maximum period of three years will be allowed to obtain the type certificate. The prototype certificate will remain valid during this period. In case of revisions to an existing prototype, a new recommendation letter must be obtained, and testing must be completed within the validity of the updated certificate. The prototype certificate itself will have a maximum validity of three years, with possible extensions. The draft also mandates regular operation and maintenance (O&M) of prototype turbines. Certification agencies must issue annual reports confirming O&M compliance, failing which disconnection from the grid may occur. All prototype wind turbines must be commissioned within 18 months of receiving the NIWE recommendation letter.