Preliminary assessment had shown promising offshore wind potential in the southern tip and west coast of India. Then a pre-feasibility report was prepared in which eight zones were identified on the Gujarat and Tamil Nadu coast
New Delhi: India has successfully conducted a first-of-its-kind LiDAR-based offshore wind profile measurement at the Gulf of Khambhat in Gujarat, the National Institute of Wind Energy (NIWE) said in a recent report.
The Light Detection and Ranging (LiDAR) unit was situated about 23 km from the Gujarat coast.
Preliminary assessment had shown promising offshore wind potential in the southern tip and west coast of India. Then a pre-feasibility report was prepared in which eight zones were identified on the Gujarat and Tamil Nadu coast.
“Ministry of Renewable Energy and NIWE in association with Facilitating Offshore Wind in India, initiated LiDAR-based measurements to validate the wind potential at the preliminary demarcated zones,” the report said.
The period of data taken for analysis was from November 2017 to June 2018.
“The primary prevalent wind direction is south of south west with a wind speed occurance of 20 per cent and secondary prevalent wind direction in North,” it said.
What made this study unique was the use of a LiDAR unit. This works similar to a underwater sonar or a radar on ground and measures wind speed and detects wind direction.
LiDAR is used extensively in the wind energy sector to measure wind potential for setting up offshore wind farms and its working is quite simple.
A wind LiDAR sits on the ground and measures the wind speed by emitting a laser beam out in the atmosphere. It then measures the time taken for that light to return to its source after being scattered back from the dust particles in the air.
Wind resource data collected for the coastline of Rameswaram and Kanyakumari in Tamil Nadu and Gujarat coast had shown reasonable potential. The preliminary assessment had suggested a potential to establish around 1 Gw capacity wind farm each along the coastline of Rameswaram and Kanyakumari in Tamil Nadu.
“Prior to the offshore installation, the LiDAR instrument was validated against the 120 m high met mast at NIWE’s test station at Kayathar in Tamil Nadu,” the report said.
Further, based on the satellite data analysis offshore potential needs to be rechecked by long-term measurements to take better decision for identifying and notifying the zones/sub-zones according to the offshore policy.
In October 2015, the government had announced The National Offshore Wind Energy Policy to establish the policy framework for tapping the offshore wind potential in the country.
The installed offshore wind capacity around the world is over 8.7 Gw and approximately an equal capacity is under construction.
The existing offshore wind farms existing and under development in United Kingdom, Denmark, Germany, Belgium, China, have 4,494 Mw, 1,271 Mw, 1,049 Mw, 712 Mw, 670 Mw capacity, respectively.