By Preeti Wadhwa
As India moves forward with its first offshore wind projects, modernising grids and developing robust offshore transmission networks will be key to ensuring their successful integration. Offshore wind farms are typically located far from key demand centres such as cities and industrial hubs, necessitating dedicated transmission infrastructure to deliver power efficiently. Without significant grid expansion, these high-potential resources cannot be fully utilised, leading to inefficiencies and increased costs. Against this backdrop, this article gives an overview of India’s offshore wind transmission infrastructure planning, challenges faced, global lessons and the way forward…
Offshore wind transmission planning
The government has planned an ambitious offshore wind bidding trajectory of 37 GW by 2030. The development of robust transmission infrastructure will be key to ensuring the success of these projects. India has introduced supportive transmission policies, including waiving interstate transmission charges for offshore wind projects commissioned up to December 2032 and exempting additional surcharges for open access consumers. Further, the sector received a significant boost in 2024 when the government approved a viability gap funding of Rs 74.53 billion. This includes Rs 6 billion for upgrading ports to meet logistical requirements.
While India has not set up any offshore wind project or a dedicated transmission line, planning for both is under way. For offshore wind transmission, so far, Central Transmission Utility of India Limited has drawn up plans for the transmission infrastructure required for 5 GW of offshore wind projects each off the coasts of Gujarat and Tamil Nadu. In line with this plan, in February 2025, Power Grid Corporation of India Limited sanctioned a Rs 4.29 billion investment for offshore wind and transmission infrastructure. This will be used for the development of a 400 kV switchyard in Vataman, Gujarat, featuring two 1,500 MVA, 765/400 kV interconnecting transformers. This switchyard will be part of the Transmission System for Offshore Wind Zone Phase 1, facilitating 500 MW of offshore wind capacity near Gujarat’s coast, specifically in Subzone B3. The project is estimated to cost Rs 3.19 billion and is set for commissioning by February 19, 2026. Additionally, a second initiative was approved to strengthen transmission capacity in the Dholera region, ensuring reliable power supply. This will involve constructing another 400 kV switchyard in Vataman, also equipped with two 1,500 MVA interconnection transformers, at an estimated cost of Rs 1.09 billion, with completion expected by March 1, 2026.
Challenges for offshore wind transmission
While offshore wind projects provide an ocean of opportunities, the setting up offshore wind transmission is not without challenges. Unlike onshore projects, where existing transmission infrastructure can often be leveraged, offshore wind farms require dedicated subsea cables, offshore substations and high voltage direct current (HVDC) or high voltage alternating current transmission systems to efficiently evacuate power.
Developers also face high risks in investing in offshore wind due to the heavy capex involved in project development and delays in setting up transmission infrastructure. Thus, a reliable offshore wind transmission system is crucial for investor confidence, as any delay or inefficiency in power evacuation could result in financial losses.
Ensuring a well-planned and well-designed transmission network is necessary to mitigate these risks and optimise power delivery. Additionally, offshore wind transmission must address intermittency issues, requiring coordination with battery storage and grid balancing mechanisms. Further, dedicated transmission corridors and offshore substations must be planned well in advance of wind farm commissioning to prevent bottlenecks and ensure seamless power evacuation.
India faces several challenges in developing offshore transmission infrastructure. In its report “Transmission System for Integration of Over 500 GW RE Capacity by 2030”, the Central Electricity Authority highlights the substantial cost disparity between offshore and onshore renewable energy transmission. The transmission cost for offshore wind stands at Rs 28.1 million per MW, nearly three times higher than the Rs 9.95 million per MW required for onshore wind and solar. This major difference is primarily due to the extensive infrastructure needed for offshore wind integration, including underwater transmission lines, offshore substations and longer-distance connections to the main grid.
Further, there are environmental and logistical challenges as cable installation must navigate sea-floor mapping, cable burial and the impact on marine ecosystems. Seabed conditions vary significantly across India’s coastline, requiring customised engineering solutions for stable infrastructure deployment. Furthermore, the country’s offshore wind speeds vary by location. While Tamil Nadu benefits from stronger and more consistent wind speeds, Gujarat’s offshore sites may face intermittency issues, necessitating innovative turbine designs and optimised transmission planning.
Another key challenge is subsea cabling, which must withstand extreme underwater conditions, marine activities and the risk of damage. Supply chain constraints, vessel availability and a shortage of skilled workers pose further bottlenecks. Currently, India depends heavily on imported HVDC cables and components, making localisation crucial for cost reduction and energy security.
Lessons from global experience
India can take valuable insights from global offshore wind leaders such as the Netherlands, the UK, Australia and the US regarding grid integration and the development of stable, high-capacity infrastructure. Establishing stable policies and regulatory frameworks, as seen in the Netherlands and the UK, can attract investment and provide long-term clarity. Effective grid integration strategies, particularly from the Netherlands, can help India develop a robust power infrastructure to accommodate offshore wind energy. Environmental and social considerations, adopted by countries such as the UK and Australia, ensure sustainable development while addressing community concerns. Infrastructure investment, especially in ports and grid connectivity, as demonstrated by the Netherlands, the UK and Australia, is crucial for efficient offshore wind expansion. Strengthening the local supply chain through incentives, partnerships and workforce training, similar to the UK and the Netherlands, can support project needs while fostering economic growth. India could also explore revenue models such as the UK’s Contracts for Difference to provide financial stability and reduce investment risks. The Netherlands has adopted a standardised 2 GW HVDC system, which has boosted supply chain investments. India should focus on local manufacturing to reduce reliance on imports. Hybrid interconnections, as seen in Europe, demonstrate the potential for regional power sharing and cross-border cooperation. Additionally, fostering collaboration among governments, industries and research institutions, as practiced in the Netherlands, the UK and the US (New York), along with inclusive stakeholder engagement, can drive innovation and ensure sustainable, long-term growth of the offshore wind sector in India.
For the upcoming 500 MW project off Gujarat’s coast, a 66 kV array cable will connect turbines to a 220 kV offshore substation. Going forward, as India expands its offshore wind projects beyond 100 km from the shore, it will need to transition towards HVDC systems, similar to those deployed in Germany and the Netherlands, which allow for efficient long-distance power transmission.
The road ahead
Going forward, offshore wind transmission can also play a key role in cross-border trade of electricity, assisting in securing energy security. The project being implemented in Tamil Nadu can enable cross-border trade with Sri Lanka. India is also planning for cross-border offshore wind transmission links with countries of the Association of Southeast Asian Nations to enhance regional energy security and grid stability.
At GRIDCON 2025, Wessel Bakker, Business Director, Offshore Power Grids, DNV, shared that several innovative transmission models are under consideration. When planning regional transmission interconnections, offshore wind farms can be integrated to form hybrid connections, allowing power to be directed to high-demand areas for better profitability. Meshed transmission grids will create an interconnected offshore transmission network that increases efficiency and system reliability. A hub-and-spoke model is being explored to establish centralised offshore hubs that distribute power through multiple transmission lines. Floating offshore substations and artificial energy islands, which have been tested in Europe, could optimise India’s offshore wind transmission in the future.
International collaborations have been instrumental in advancing India’s offshore wind sector. Partnerships with the European Union, Denmark and the UK have delivered crucial technical expertise and financial support. A key outcome of these collaborations is the Centre of Excellence for Offshore Wind and Renewable Energy, a joint initiative by the Indian and Danish governments. These cross-border partnerships are strengthening investor trust and creating a foundation for sustainable growth in India’s offshore wind industry over the long term.
For investors, policymakers and industry stakeholders, offshore wind could create new opportunities for manufacturing, skill development and maritime infrastructure. The coming decade will likely see India transition from being an offshore wind novice to a significant player with unique expertise in developing these resources in challenging tropical conditions. The country’s offshore wind sector is set for exponential growth, but success will depend on the development of robust and efficient transmission infrastructure. By learning from global best practices and addressing policy, financing and technological challenges, India can tap its vast offshore wind potential.
