Reimagineering the Wind Energy sector under the Aegis of AM/NS India

Wind power is a clean and renewable energy source. Wind turbines harness energy from the wind using mechanical power to spin a generator and create electricity. Not only is wind an abundant and inexhaustible resource, but it also provides electricity without burning any fuel or polluting the air.
The wind sector in India has been rapidly growing in recent years, with the country being fourth largest producer of wind energy in the world. According to the Ministry of New and Renewable Energy (MNRE), India’s wind energy capacity has reached 41.9 GW as of February 2023.

National Wind-Solar Hybrid Policy announced in May 2021 with a aim to promote large-scale grid-connected wind-solar hybrid projects in the country. The MNRE has also recently issued a draft guideline for the development of offshore wind energy projects in India. It is expected to accelerate the growth of the renewable energy sector in India and contribute towards achieving the country’s target of 450 GW of renewable energy capacity by 2030.

Indian government has taken several initiatives to promote wind energy, including policy support, tax incentives, and financial incentives for developers and investors.

The Indian Wind Turbine Manufacturers Association (IWTMA) has been advoca-ting for the establishment of an export promotion council for wind energy equipment. This council would help.

Indian wind turbine manufacturers to expand their businesses globally and increase exports.
The Indian wind sector has also been focusing on improving the efficiency and reliability of wind turbines. The Centre for Wind Energy Technology (C-WET) has been conducting research and development in the field of wind energy to improve the performance of wind turbines.

Wind Turbine Basics:
There are different types of wind turbines, depending on the geography, output, cost etc. wind turbine use steels, hybrid (Concrete & steel), and concrete as a raw material.

• Steel:

– Lattice tower
– Tubular tower
– Space frames

• Hybrid (Concrete Steel) (offshore app-lications) Hybrid (lower part concrete, upper part steel)
• Concrete (including offshore)

– Precast pre-tensioned
– Precast post-tensioned
– In-situ

A wind turbine is a device that converts kinetic energy from the wind into electricity.

A group of wind turbines is called a wind farm. On a wind farm, turbines provide power to the electrical grid. These turbines can be found on land (onshore) or at sea (offshore).

Wind turbines are manufactured in a wide range of shapes and sizes, but the most common design is the one with 3-blades mounted on a horizontal axis. Their output ranges from as small as 100 kilowatts to as big as 12 megawatts.

They can be placed in a huge range of locations: on hills, in open landscapes, fixed to the bottom of the sea – and we can even have floating turbines in deep waters!

How does a wind turbine work?
There is a wind vane 1 at the top of each turbine: this tells the turbine the speed and direction the wind is blowing.

The turbine then rotates on the tower to face into the wind, and the blades 2 rotate on their axis to create maximum resistance against the wind.

The wind starts turning the blades which are connected to a hub and a low-speed shaft 3.

The low-speed shaft spins at the same speed as the blades (7-12 revolutions per minute). But we need a much faster rotational speed for the generator to produce electricity.

That’s why most wind turbines have a gearbox 4, which multiplies the rotational speed of the low-speed shaft by over 100 times to the high-speed shaft 5, which rotates up to 1,500 revolutions per minute.

This is connected to a generator 6, which converts the kinetic energy into electricity.
Turbines that do not have a gearbox are connected directly from the hub to the generator 6 through their axis (this is called ‘direct-drive’).

Most widely used design in tubular tower design.

• The steels plates are used in tubular towers, support structures for stator and rotor brakes.
• The tubular steel towers use 12mm, 14mm, 16mm, 18mm, 20mm, 22mm up to 63mm in S355 J2+N, J0,JR etc grade
• The tubular towers use plates in width 1250mm, 1500mm, 2500mm and 3000mm.
• The trend is to use high strength steel plates in combination with wider width plates for reducing the tower weight and joints respectively. Steel plates for support structures range from 25mm to 50mm in S 355 J2 grade.

One key component in the construction of these turbines is heavy steel plates, which are used for their durability, strength, and versatility.
Heavy steel plates are an essential component in the construction of wind turbines. They are used for a range of applications, including the tower, foundation, and rotor blades. In the tower, the plates are used to provide the structural support necessary to withstand the strong winds and turbulent conditions at higher altitudes. The foundation requires heavy steel plates to support the weight of the tower and ensure stability, while the rotor blades require plates for their internal components, such as the hub and pitch system.
The use of heavy steel plates is especially important in larger wind turbines, which require stronger and more durable components to withstand the increased stresses and loads. For example, the latest generation of offshore wind turbines can have a rotor diameter of up to 220 meters and stand over 250 meters tall. These turbines require steel plates that can withstand high wind speeds, waves, and corrosion from the harsh marine environment.

Another advantage of heavy steel plates is their flexibility in design. Wind turbine manufacturers can customize the plates to meet specific project requirements, such as thickness, width, and length, depending on the turbine’s design and location. This flexibility also extends to the type of steel used, with manufacturers able to choose from a range of high-strength, low-alloy steels, and carbon steels.
There is a growing need from the wind tower segment for steel solutions, value engineering, cost cutting & improved efficiency in operations. Value Proposi-tions from AMNS for Wind segment.

• Supply of TMCP plates against Furnace Normalized/Normalized Rolled plates for improved Weldability & handling.
• Supply of steel plates as per exact design, and tight dimensional tolerances
• High strength steel (S 420 Etc.) replacing Standard S 355 grades
• Cost saving model for use high strength steels (welding, handling, cutting, etc.)

Advantages of wider widths:

• Reduction in the number of shells in the tower section
• Savings by elimination of additional operations like, cutting, handling, welding, assembly etc.
• Reduction of circumferential welding -30 % cost saving through reduction of welding

Advantages of High Strength:

• Taller towers for enhanced power generation
• Greater stability and integrity of structure
• Cost saving due to reduced weight of shells and stiffeners

Overall, the wind sector in India is witnessing significant growth and deve-lopment, with the government taking various initiatives to promote wind energy in the country.
The latest happenings in the sector indicate that the industry is moving towards greater efficiency, reliability, and sustainability. With the right policies and investments, the wind sector in India has the potential to become a major contri-butor to the country’s energy mix and play a key role in reducing greenhouse gas emissions.

ArcelorMittal Nippon Steel India
Mr. Dilip Chandra, Section Head
Web : www.amns.in/heavy-plates