**Author details**

The static stability of the foundation is carried out, and the draft is estimated to be 4 m from the bottom. As the foundation needs to be towed for a long distance, it is essential to identify the natural frequencies and response amplitude operations (RAO). Natural frequencies and RAOs are computed for three translation modes and three rotation modes. It is observed that the

Offshore wind being pollution-free would be an ideal solution to meet the increasing demand as Indian coast is blessed with significant winds. The Ministry of New and Renewable Energy (MNRE) has published the offshore wind policy for offshore wind development in India [23]. Offshore wind would be commercially viable, if potential sites are identified and economical substructure concepts along with installation methodology are developed considering local conditions. Hence, studies were taken up to identify potential sites, perform commercial viability studies, and design the optimum substructure configuration along with installation

Wind assessment studies based on secondary wind data like offshore satellite winds and onshore mast data by various organizations helped in identifying potential sites along the coast of Gujarat and Tamil Nadu. Commercial viability studies based on these data were carried out and indicated the need for suitable incentives by the Government of India to attract huge investments for offshore wind industry. NIWE has attempted to capture the offshore

natural frequency is far away from the encounter frequency of waves (5–10 s).

**6. Summary and conclusions**

**Figure 12.** Installation methodology of gravity foundation.

164 Stability Control and Reliable Performance of Wind Turbines

methodology.

Satya Kiran Raju Alluri\*, Devender Gujjula, Krishnaveni B, Dhinesh Ganapathi, S.V.S. Phanikumar, M.V. Ramanamurthy and M.A. Atmanand

\*Address all correspondence to: raju@niot.res.in

National Institute of Ocean Technology, Chennai, Tamil Nadu, India
