In our endeavour to replace fossil fuel based energy by the renewable sources, wind energy is one of the performing saviour for the human kind. In India, high wind velocity sites are limited on the shore, in addition to this, scares land availability is creating limitations in developing onshore wind farms day by day. In such situation contribution from offshore wind energy in the gamut of renewable energy would be a boon.
Wind in sea is much stronger, less turbulent, consistent and the average speed is also high. So can handle bigger capacity of wind turbines and can produce more energy. Thus, offshore wind energy has huge potential in India, provided the initial technical, operational and regulatory challenges are efficiently met.
Offshore History at a Glance
Way back in 1991, world’s first offshore wind farm of 5MW capacity was developed at Vindeby in Denmark with 11 wind turbines. Those 11 machines were responsible for the supply of uninterrupted power to the 2200 households of the city. That was a path breaking pilot project to make people believe that wind turbines can also be operated at sea. From that point of success, slowly the development of offshore wind farms had come in to reality in many countries in Europe and later across the world. After 25 years of dependable service, in 2017 world’s first offshore wind farm was dismantled due to commercial reason.
In past three decades, technology has improved a lot, supply chain management has also developed to a better level, people have gained good experience, putting all these factors together is making offshore wind projects as an emerging, more feasible and promising renewable energy resource. This sector is now projecting a decent global growth planning for future, starting from 23GW in 2018 to a modest 1000GW in 2050.Thereore, showing a potential to share about 17% of total global installed wind energy capacity of 6044 GW by that time.
World At This Moment
As on 2019,out of total cumulative installation of 29.1 GW of offshore wind turbines, Europe leads the world with 22 GW and with a target to increase it by four-fold to 78GW by 2030 and ten-fold to 215 GW by 2050.Consiquently, most of the global offshore installations – about 90% – are now concentrating in North Sea and nearby areas of Atlantic Ocean.
Europe stands in an advanced status and would also remain so for next 10 years or little more. After that, China is estimated to emerge as the biggest player in less than two decades , surpassing Europe. The US is also expected to grow up at a faster pace and from today’s less than 1 GW, it is estimated to expand up to 23 GW by 2030 and up to 164GW by 2050.
As far as Asia is accounted for, China is leading now. Nevertheless, an estimates shows that by 2025 it will fall back significantly due to the aggressive participation of India and other Asian countries like Japan, South Korea, Taiwan and Vietnam.
India to Kick Start
Surrounded three side by the sea, the coastline of India is about 7500 km long and therefore, carries a good potential for harnessing offshore wind. Only question is, whether it could sustain the competition with cheaper onshore wind energy? This is probably the cause, that harnessing of offshore wind energy so far not taken off in this country.
Though, India Government had notified the “National Offshore Wind Energy Policy” in 2015, but ground activity on offshore wind came up only during 2017, when Suzlon Energy along with NIWE (National Institute of Wind Energy) and NIOT (National Institute of Ocean Technology) had installed LiDAR (Light Detection and Ranging) based Data collection platform at Gulf of Khambhat and Kutch in the state of Gujarat.
At present, a short term target for drawing 5GW power from offshore wind installations by 2022 has been chalked out. Another target to harness 30GW by 2030 has also been set by the government. The coast lines of Tamil Nadu, Gujarat and Maharashtra has been primarily identified for this purpose.
Out of targeted 5GW in the first phase, Government wants to install 1GW capacity as a pilot project in the coast of Gujarat. For that, geophysical study for 365 KM2 area has already been completed and geotechnical & met-ocean studies are either done or at an advanced stage, ‘Stage -1’ clearance as per the policy guide line has also been obtained, ‘environmental impact assessment’ is also almost completed by National Institute of Oceanography, Goa, but for some unknown reason the project is getting delayed inordinately and the tender is yet to open.
Looking to the situation, it appears that the target of 5GW by 2022 will be difficult to meet. Though meeting 30GW by 2030 is still possible.
In general, limitation in case of offshore wind energy is that, 80% of world’s potential is available in the sea areas where the depth of water is above 60m and this limitation is calling for the development of commercial floating turbines in the long run. However, for India at this moment this isn’t a limiting factor, harnessing up to 70GW is well possible with the conventional foundation method as estimated by MNRE.
Another challenge would be the size of turbines. Offshore turbines are typically bigger in size, they ranges from 5MW to 10 MW. In India this size of turbines are not developed till now. Biggest onshore turbine technology the country has is 3MW and commonly used biggest turbine size is 2MW/2.1MW.Therefore, I think either bigger turbines from Europe has to be imported or the initial erections would be with the modified offshore version of existing 2MW turbines only and scaling up in size will happen later.
Third point is, offshore turbines needs stronger and bigger structures and foundations to sustain in the marine environment. Operation and maintenance service will also be a challenge. All these factors will add to the cost and this has to be neutralised by the way of achieving higher efficiencies in order to stand commercially viable in the long run.
The Bright Side
Though the sector is unexplored to India and the team going to engage in it have to learn a new technology and methods in terms of erection, commissioning, operation & maintenance management, but the positive side is that a huge pool of engineers and technicians are available in the country who have already developed expertise in onshore wind turbines. India has a total onshore installed capacity of 38GW and expanding and this is creating a continuous opportunity for ‘on the job’ training for engineers and technicians. I personally believe, this enormous onshore experience, with necessary reinforcement with further inputs and quick training will help to build up a pool of offshore experts within a very short period of time. I took similar strategy in hiring non-wind personnel two decades back, when we were going in a big way with onshore projects in India and abroad.