Offshore Wind
Introduction
Globally offshore wind is about two decades old history with the first offshore wind turbine in Denmark in 1991 which has been decommissioned in 2017. As of now, offshore wind energy projects of more than 57 GW are installed in 18 different countries, of which leading countries are UK, China, Germany, Denmark and The Netherlands.
India is blessed with a coastline of
about 7600 km surrounded by water on three sides and has good prospects of
harnessing offshore wind energy. Considering this, the Government had notified
the “Nationaloffshore wind
energy policy”as per the Gazette Notification dated 6th October 2015. As per the policy, Ministry of New
and Renewable Energy will act
as the nodal Ministry for development of Offshore Wind Energy in India and work in close coordination with other
government entities for Development and Use of Maritime Space within the Exclusive Economic Zone (EEZ) of the
country
and shall be responsible for overall monitoring of offshore wind energy development in the country. National
Institute
of Wind Energy (NIWE), Chennai will be the nodal agency to carryout resource assessment; surveys and studies in
EEZ
demarcate blocks and facilitate developers for setting up offshore wind energy farms.
Absence of any obstruction in the sea offers much better quality of wind and its conversion to electrical energy. Offshore wind turbines are much larger in size (in range of 8 to 14 MW per turbine) as against 2-3 MW of an onshore wind turbine. While, the cost per MW for offshore turbines are higher because of stronger structures and foundations needed in marine environment, the desirable tariffs can be achieved on account of higher efficiencies of these turbines after development of the eco system.
Facilitating Offshore Wind Energy in India (FOWIND)
Is a project implemented from December 2013 to March 2018 by a consortium led by Global Wind Energy Council (GWEC) and supported by European Union (EU) to assist India on its offshore wind power development and in turn contribute to India’s transition towards use of clean technologies in the power sector. The project focused on the States of Gujarat and Tamil Nadu for identification of potential zones for development through techno-commercial analysis and preliminary resource assessment. The outcomes of the FOWIND are summarized in the following reports.
2. GlobalOffshore Wind Policy Assessment Outlook.
3. Pre-FeasibilityReport For Offshore Wind Power Development
In Gujarat.
4. Pre-Feasibility Report
For Offshore Wind Power DevelopmentIn Tamil Nadu.
5. Report On Supply Chain, Ports And Logistics.
6. Grid Integration Study For Offshore Wind Firm
DevelopmentIn Gujarat And Tamil Nadu.
7. Feasibility Report For Offshore Wind Power Development
InGujarat.
8. Feasibility Report For Offshore Wind Power Development
InTamil Nadu.
9. India’s Offshore Outlook From 0 GW To 5 GW.
First Offshore Wind Power project in India (FOWPI)
Is another project getting implemented from December, 2015 by a
consortium led by COWI and supported by European Union with an objective to
provide assistance up to the stage of Pre-Financial-Investment-Decision
(Pre-FiT) and provide general assistance for capacity building of Indian
stakeholders within offshore wind sector. The following reports are already
published under FOWPI project.
2. MetoceanWeather Windows for installation.
3. Metocean Data Requirements.
4. Proceduresfor Offshore Wind.
5. FOWPIWind Turbine Layout and AEP.
6. Advisory Electrical Concept Design.
Identified Offshore Wind Zones for Initial Project Development
Based on the preliminary assessment from satellite data and data available from other sources eight zones each in Gujarat and Tamil Nadu have been identified as potential offshore zones for exploitation of offshore wind energy. Initial assessment by NIWE within the identified zones suggests 36 GW of offshore wind energy potential exists off the coast of Gujarat only. Further, nearly 35 GW of offshore wind energy potential exists off the Tamil Nadu coast.
Strategy Paper for
Establishment of Offshore Wind Energy Projects
Ministry has issued the strategy for development of offshore wind in July, 2022 through ‘Strategy Paper for Offshore Wind Development’ after stakeholders’ consultation. As per strategy, 03 following models has been envisaged for the development of offshore wind:
1) Model-1: This model will be followed for the sites for which studies/ surveys are conducted by NIWE/Govt entity, such as present site of Zone B off Gujarat Coast.
2) Model-2: The model will be followed for the sites for which studies/ surveys will be conducted by prospective developers (without any exclusivity on seabed) for participation in offshore bids proposed to be conducted by Govt.
3) Model-3: The model will be followed for the sites for which studies/ surveys will be conducted by prospective developers (with exclusivity on seabed) and project development will be through bilateral agreements or for captive consumption or power exchange basis.
Guidelines for Offshore Wind Power Assessment Studies and Surveys
The ‘Guidelinesfor Offshore Wind Power Assessment Studies and Surveys’ was approved and issued by NIWE in September, 2018 to facilitate stakeholders who are interested for carrying out the study/survey activity for development of offshore wind energy project.
Offshore Wind Resource Assessment through LiDAR
The offshore wind energy potential estimation carried out through satellite data needs to be validated through actual ground measurements in order to make the data bankable. Ministry has decided to launch a measurement campaign deploying Light Detection and Ranging (LiDARs) at the identified zones off the coast of Gujarat and Tamil Nadu. One LiDAR was commissioned in November 2017 for Offshore Wind Resource assessment in identified zone-B off the coast of Gujarat nearly 25 km away from the port of Pipavav. Two years data collected from the deployed LiDAR has been analysed and the report is published at NIWE’s website.The raw data can be accessed from NIWE website (https://niwe.res.in/department_wsom_lidar_raw_data.php). As per the report, the annual average wind speed at the locations is observed to be 7.52 m/s at 100m hub height.
Oceanographic, Geophysical and Geotechnical studies
In addition to the wind data, the viability of offshore wind projects also largely depends on the condition of site in terms of oceanographic data, geophysical and geotechnical data. Ministry has planned to carry out the required study in this regard through NIWE and provide the basic data to the stakeholders before commencement of the bidding so as to mitigate the risks. Geo-physical Survey for 365 Sq. km (Gujarat) for 1.0 GW project capacity in Gujarat has been completed. One rapid EIA has also been carried out for this site.