The main benefit of going offshore is that wind conditions are known to be steadier and less seasonal and provide power close to load centres compared to onshore
For long, Tamil Nadu has not been able to tap the vast potential of wind energy a long coastline offers.
While onshore wind farms, mostly located in the Shencottah and Palakkad passes, have been able to harness wind energy to the maximum, the offshore potential has only been talked about till now – primarily due to the prohibitive costs.
Now, the Centre for Study of Science, Technology and Policy (CSTEP) is carrying out a pre-feasibility study, wherein eight zones between Kanyakumari and Ramanathapuram districts have been identified as high potential areas — excluding fishing areas, military zones and oil and gas industry.
The main benefit of going offshore is that wind conditions are known to be steadier and less seasonal and provide power close to load centres compared to onshore. Also, land availability is less likely to be a bottleneck for development.
Lot of aspects are being explored as part of the study. The geographical aspect of shallow water depth and economic criteria, including proximity to ports, infrastructure facility to export the power produced and the wind availability, are all being considered.
“In a State having a long coastline and with a proven record in producing wind energy by installing onshore wind mills, the potential of generating power from offshore wind mills is high,” a senior official of the Energy Department said.
With substantial funding from the European Union, Global Wind Energy Council (GWEC)-led consortium is undertaking the study in close cooperation with the Ministry of New and Renewable Energy (MNRE) under the Indo-European Cooperation on Renewable Energy program. The study is called Facilitating Offshore Wind in India (FOWIND), the official said.
“It is too early to put out any numbers about the energy potential, as it is directly linked to the ocean block availability and a more accurate knowledge of wind resource,” said Meera Sudhakar, a researcher at CSTEP.
The most promising zones identified in the pre-feasibility study extended over an area of about 10,500 square kilometres of ocean floor and could support around 63,000 MW of offshore wind capacity. The preliminary estimates of cost of energy from offshore wind in Tamil Nadu would be at Rs. 12 to Rs.13 a unit - four times higher than current tariffs offered for onshore wind in Tamil Nadu, she said.
Although the turbine technology was similar to onshore wind, the reason for the high cost difference was because of the high foundation costs as well as installation and maintenance cost, she noted.
T. Shivaraman, vice-chairman of Orient Green Power Company Ltd., said: “Only when work begins, the industry will know what it actually costs. It’s too early to talk about cost now.”
An industry analyst said, “Offshore foundation has to be put in shallow waters. It also depends on how the shallow the water is. Thus the cost varies. You need wind first, then you need the grid line there and the machine should be in a working condition. Getting dredger ships are also expensive.”
