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Saturday, January 13, 2024

Offshore wind in Tamil Nadu: from potential to reality

by Akshay Jaitly, Charmi Mehta, Renuka Sane and Ajay Shah.


The world of renewables is comprised primarily of solar and wind. Of these, solar electricity suffers from the limitation of dwindling away in the evening, at precisely the time at which electricity demand rises. This makes wind particularly important. There is a good deal of onshore wind generation in India. What is different and potentially superior about offshore wind?

  1. Wind speeds tend to be higher offshore than on land. A wind turbine operating at a wind speed of 24 kph can generate twice as much energy as a turbine operating at a wind speed of 19 kph (American Geosciences Institute, 2023).
  2. The wind offshore tends to be more consistent, with higher power capture for a greater number of hours per day.
  3. Onshore wind requires land resources. Offshore wind is built in the open sea where land rights are cheaper, and it is easier to go to bigger blades.
  4. Offshore wind does not impose noise pollution upon the human population.

These benefits, of course, come with a problem, that construction of windmills in the high seas is more difficult when compared with building on land. Windmills are best placed at locations with high wind. Figure 1 shows that Tamil Nadu is a hot spot for offshore wind in India. It is interesting to notice that Sri Lanka is also a hotspot for offshore wind (Figure 2).

Figure 1: Wind speeds off the Indian coast

Source: India Wind Potential Atlas (NIWE, 2019).

Figure 2: Wind speeds off Sri Lanka.

Source: Technical Assessment by World Bank, IFC and ESMAP (2020).

There is an analogy between offshore wind in Sri Lanka, and hydel resources in Nepal and Bhutan. Given the correct arrangement of foreign policy (Subramanian, 2023), the Indian private sector can possibly play a leadership role in building electricity generation in Sri Lanka, as has been the case with Bhutan.

Putting these facts together, there is an important natural resource in Tamil Nadu, and its vicinity, through which vast renewable electricity generation can become possible, given the correct configuration of policies and state institutions that create conditions of investibility. We can dare to hope that very large offshore wind generation can take place off the coast of Tamil Nadu, which would attract energy-intensive firms to operate in the region, and enabling sale of electricity into locations far from Tamil Nadu.

Public economics for offshore wind

We can imagine an uncoordinated rush by the private sector to venture out into the seas and put up wind turbines. They would jostle with each other to build on the best sites. Each wind turbine would have to face the problem of transmitting energy to the mainland. There are three areas where policy makers can be useful:

  1. Ownership of the sea-bed and property rights: In a world without clarity on property rights, the private sector would experience conflicts when building wind turbines. There is a negative externality as multiple construction projects which are physically near each other impose a certain amount of chaos upon each other, and the presence of a windmill diminishes the energy production of nearby windmills.The sea-bed should be treated as a scarce natural resource, akin to the electromagnetic spectrum. There is a role for the state in establishing property rights, and auctioning off ownership of the sea-bed to private persons. The coercive power of the state would be used to create property rights for private persons, following which private persons would trade in blocks of sea-bed (akin to transactions in privately owned land or on the electromagnetic spectrum), and the government would enforce against encroachment. The negative externality problem during construction can be addressed by modified property rights which decongest each construction site for the construction period, by expanding the notion of property rights associated with each geographical location, to exclude other persons for the period of construction.
  2. Economics of transmission: Each wind turbine would have to face the problem of transmitting energy to the mainland. Every generation company would benefit from more convenient access to high capacity transmission lines. There is a natural monopoly problem in the transmission infrastructure - it is likely that a single transmission company will emerge within each geographical area. There is merit in using state power to coerce this firm on open-access rules (so it cannot deny transportation to any private person) and on price regulation.
  3. Data as a public good: The government can add value by spending taxpayer money to construct a dataset on wind speed and releasing this into the public domain. This activity involves no use of coercive power, other than the coercion that undergirds taxation. The government would merely release data on a website as a public good, and in no way preclude private persons from expending resources to create data on their own. For the government released data to be credible, it would have to be collected by trusted agencies, experienced in offshore wind data collection; the role for the government should be one of only contracting-out the construction of the data.

While electricity in India is largely a state subject, the sea-bed falls under the union government jurisdiction through Article 297 of the Indian Constitution through which the Parliament has enacted the Territorial Waters, Continental Shelf, Exclusive Economic Zone and Other Maritime Zones Act, 1976. Thus we can envision a two-part policy story for offshore wind, where the union government auctions off blocks of sea-bed, and the state government deals with everything connected with electricity. Once the energy reaches landing stations at the shore, it is just ordinary electricity and fits into the mainstream electricity market exactly as with onshore wind turbines.

How the Indian journey has unfolded

The union government has decided that offshore wind production will commence in Gujarat and Tamil Nadu. A union government agency named the National Institute of Wind Energy (NIWE) plays an important role in this field including that of being the designated counterparty for contracts. It plays a expansive role, akin to an offshore wind central planner. Transmission will be run by a union government PSU, the Power Grid Corporation of India Limited (PGCIL). No role is envisaged for state governments.

In 2018, NIWE published its first tender for an offshore wind block auction off the Gujarat coast. However, it did not receive bids and consequently had to be called off after multiple extensions (Deshpande, 2021). Since 2022, the Union Government has released (i) a national Strategy Paper for the Establishment of Offshore Wind Energy Projects and (ii) a draft tender for Sea bed leasing for offshore wind energy projects which pertains to locations off the coast of Tamil Nadu. These releases help improve policy predictability.

The proposed contracting model

Project costs in offshore wind are high, particularly in contrast to developing renewable energy plants onshore. Costs also vary as per the depth of waters and distance from shore. Operating offshore wind turbines involves higher maintenance requirements (Koch, 2012). First movers face higher costs on account of uncertainty and the inevitable mistakes.

NIWE has proposed three alternative contracting models in its strategy paper. Model A is for projects where surveys and assessments have been completed, and the site is ready for development. Model B is model A without viability gap funding ("VGF?). Model C is a fully bundled model with end-to-end responsibility placed upon the project developer, including site identification. The tender released (for the sea bed off the coast of Tamil Nadu) follows model A (NIWE, 2023). Table 1 summarises this proposed contract design.

Table 1: Risk-responsibility allocation across proposed offshore wind contracting models
Factors Risks/responsibility Model A
Government support Bridging financing gaps VGF (Union; unallocated)
Transmission charges Waived
Strategic and commercial risks Identifying sites for offshore wind farms Gov (Union)
Site assessment surveys Gov (Union)
Local factors Transmission infrastructure Gov (PGCIL)
Evacuation of power Gov (PGCIL)
Licenses Private
Power offtake guarantees None

Site characteristics have a substantial impact upon the prospective return on equity. The MNRE/NIWE supplies its assessment of each site. A careful examination of the data released by MNRE/NIWE is required. Potential developers may invest significant time and resources in constructing private sector data if there are limitations in the government-released data.

The selected bidder must set up the turbines offshore and connect each turbine to the offshore agglomeration facility (which will be constructed and managed by PGCIL). While the model mentions accessing VGF from the union government, the mechanism is not adequately spelled out. Is this policy strategy conducive to investibility?

i. Site selection and exclusivity:

Site selection is best done by potential wind farm developers. Developers face the consequences of, and are best placed to take decisions on sites when faced with a certain amount of data. They will commission the creation of additional data optimally. Under Model A, sites have been selected by NIWE. We expect that serious developers will construct their own datasets and may chafe at the locations pinned down by NIWE.

The next issue is that of exclusivity. Developers like to have a certain exclusive period, where no other construction takes place, in order to reduce the complexities of coordination across multiple construction projects. The exclusivity period for the sea-bed is set to five years, with a maximum extension of one year. The average time taken to set up a mid-size offshore wind farm, globally, is four years. In India, this is likely to attain a higher value (MOSPI, 2023).

Auctioning the exclusivity period itself can be a way to decide what a 'sufficient' period should be. In countries where confidence in offshore projects has been high, auctions are witnessing site tenures being awarded based on an auction in which the highest bidder wins the site (Exeter, 2022). For example, the Round 4 auction for sites (held in 2021) in England and Wales saw the highest bidder paying Euro 1bn upwards in option fees, payable annually (for ten years) for exclusive sea-bed rights on an 8 GW of offshore wind.

ii. The problem of transmission:

In offshore wind contracts in Northern Europe, the evacuation infrastructure for the electricity is generally created by the developer (and in some cases such as in the UK, later carved out and sold to a third party) or contracted out (separate from the offshore windfarm contract) to a private transmission service provider. Under Model A, this function has been assigned fully to the state-owned transmission company - PGCIL. PGCIL has no prior experience in developing transmission for offshore wind and it carries the burden of being a public sector organisation.

Whether managed by PGCIL or some other firm, regulation is required so that future developers are provided access to non-discriminatory evacuation infrastructure and services, perhaps using common carrier principles. While one block / site is up for auction today, numerous offshore plants will come up in the future in close vicinity. There may be shortages or exorbitant pricing of transmission, particularly in the absence of non-discriminatory access.

In addition to the risks from power evacuation, risks from unscheduled downtimes can induce losses, and contract terms will determine who bears this risk. For example, in Germany, the costs of curtailments/incapacities were transferred to the consumer. In contrast, costs remained with the project owner in China despite their lack of control over the risk (Gatzert, 2016). The government's decision to manage the complete evacuation responsibility may prove problematic in the event that higher transmission losses or shutouts imposes important risks upon the developer. If the preference is for power evacuation to be managed by PGCIL, contractual provisions on liquidated damages must adequately cover for downtimes that are not caused by the fault of the developer and other transmission losses.

iii. Regulatory burdens

Unlike transmission and distribution, power generation has no market failure problem. It is hence important to envisage a contract design that harnesses private sector expertise, without added layers of government involvement. At present, establishing an offshore wind farm will require a set of seventeen different clearances and licences from a host of ministries, including the prerequisite of block approval from the Ministry of Defence. Seven of the seventeen clearances are necessary even before one can make a bid, and the rest are post-award. The sector also includes a specific licensing regime that extends to how new offshore assets connect and interact with the grid. This requirement for multiple permissions detract from the vision of property rights in the hands of a private person.

Further, approvals and no-objection certificates may be required from State Governments for transmission and evacuation infrastructure-related provisioning and any other clearances as may be legally required to establish and operate offshore power plants - as in the case of oil and gas pipelines (NIWE, 2022a, NIWE, 2022b).

It might be useful to consider if some project-related (as opposed to bidder related) approvals can be obtained ahead of time and made part of the bid package. This will reduce risk for bidders and may lead to more attractive bids.

Lastly, as with any nascent industry, policy and regulatory frameworks are likely to evolve and change over time - and existing concessionaires should be contractually protected from this through adequate 'change in law' and 'change of scope' provisions.

Under the present policy strategy, offshore wind generation requires the firm to have a high level of government engagement, and exposure to policy risk. This problem may encourage foreign firms to find local partners and enhance the required rate of return, i.e. hamper investibility.

iv. The role of the union government:

The present policy strategy suggests a offshore wind industry that is run out of the union government. This vision will sit uneasily with the primary role of the state government in electricity regulation and the electricity business once the energy hits the shore. Since vessel availability and transport infrastructure are critical to offshore wind farm development and often contribute to delays, cost overruns ((Koch, 2012), and litigation, the State's port infrastructure can be adapted to facilitate project management. Proximity of the Thoothukudi port to the proposed site is an advantage, and logistics facilities such as (i) storage areas for component assembly and manufacturing, and (ii) berth infrastructure can be developed to support upcoming offshore wind plants (Auroville Consulting, 2022). Such thinking is downplayed in a union-dominated policy process.

Assessing the outlook

Our analysis suggests that there is a considerable gap between the natural resource potential for offshore wind in South Asia and its tangible translation into RE capacity. The sea-bed lease tender was released in September 2023 with a deadline of 28 November 2023. In our knowledge, no bids have emerged.

Electricity is a concurrent list subject under the Indian Constitution, with both the union government and the state government having the right to make law over aspects of the sector. Sea-bed jurisdiction appears to clearly lie with the union. It would make sense to rely on the state government to a greater extent.

There are significant manufacturing and transportation challenges associated with the bulky parts of offshore wind facilities. Both Tamil Nadu and Gujarat are strong in manufacturing, and are natural sites where a private industry could develop that will undertake this manufacturing, and play a role in offshore wind sites hundreds of kilometres away.

The arguments presented earlier in this article show that thinking from first principles, the role of the state in this field is (a) Establishing property rights with auctions of chunks of sea-bed, including a special kind of exclusivity during construction; (b) Ensuring open access and price regulation for the natural monopoly of transmission; (c) Possibly adding value by constructing and releasing a robust dataset with wind speed. There is merit in evolving the policy strategy towards these three pillars.


American Geosciences Institute. 2023. What are the advantages and disadvantages of offshore wind farms?, National Academy of Sciences.

Deshpande, T. 2021. Why India's Offshore Wind Energy Potential Remains Untapped, IndiaSpend. 26 November 2021.

NIWE. 2023. Strategy for Establishment of Offshore Wind Energy Projects, Ministry of New and Renewable Energy, Government of India. September 2023.

Koch, C. 2012. Contested overruns and performance of offshore wind power plants, Construction Management and Economics, 30:8, 609-622.

Infrastructure and Project Management Division, Ministry of Statistics and Programme Implementation. 2023. Quarterly Report on Mega Projects.

Laido et al. 2022. Impacts of Competitive Seabed Allocation for Offshore Wind Energy, University of Exeter. April 2022.

Gatzert et al. 2016. Risks and risk management of renewable energy projects: The case of onshore and offshore wind parks, Renewable and Sustainable Energy Reviews, Volume 60. July 2016.

Auroville Consulting. 2022. Unlocking Offshore Wind in Tamil Nadu. Sustainable Energy Transformation Series.

Subramanian, A. 2023. Answers in the offshore wind.The Indian Express. 23 March 2023.

Akshay Jaitly and Renuka Sane are Co-founder and Research Director, respectively, at TrustBridge Rule of Law Foundation; Charmi Mehta and Ajay Shah are Research Associate and Co-founder, respectively, at XKDR Forum.

1 comment:

  1. The wind resources off Tamilnadu & Sri-Lanka is akin to the oil resources in the Middle-East - a huge potential.

    I have a few questions;

    1. Have there been discussions and consultations with potential bidders so their inputs and suggestions are incorporated into the bidding documents?

    2. Given the low trust environment, how would the Government of India reassure potential bidders ? Can all the 17 approvals and other permissions be got before the bidding is open, so risk/cost of getting the approvals/permissions is removed from the equation? How can the Government of India and Government of Tamilnadu work together to reassure/derisk the potential bidders against any policy changes in future?

    3. PGCIL is a state monopoly. Does this deter potential bidders? What are the options to ensure PGCIL creates the required infrastructure on-time?

    4. Will the power buying arrangement be akin to a PPA ?

    5. Is there a case to make electricity costs flexible depending on demand and supply? Will this make the business case for potential bidders more flexible? Is there already work going on to make electricity costs flexible in India?

    Thanks for sharing this paper.


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