Bearings Behind the Blades: Insights into the Market

In a medium-sized wind turbine, around 8,000 parts work in harmony to convert the wind’s kinetic energy to what we seek, clean electrical energy. These parts also include a few dozen bearings, which make this conversion smooth, efficient, and reliable. The three veins of a wind turbine—the main shaft, gearbox, and generator—rely on bearings to distribute the loads evenly, minimizing friction and wear essential for the seamless rotation of the turbine blades and ensuring optimal energy production. Hence it is safe to assume that the wind energy bearings market will climb the ladder parallelly as the wind energy capacity across the globe rises.

Optimizing the Output : From Blades to Gearbox

Bearings are mechanical components used to reduce friction between the moving parts by allowing two surfaces to roll over each other instead of sliding. In a wind turbine, bearings facilitate the smooth rotation of blades, yaw systems, and gearboxes. Gearboxes, which translate the low-speed main shaft to the high-speed generator shaft, are the most commonly used application for bearings constituting around 56% of the total wind energy bearings market. The main shaft that connects the turbine blades to the gearbox is another significant application, followed by electrical generators that convert mechanical energy into electricity. Other applications, such as Yaw and Pitch, constitute a small portion of the market.

Considering the harsh working conditions, such as varying wind speeds, temperature fluctuations, and high loads, the industry invests a lot of resources to ensure only highly reliable bearings find their place in the wind turbines. In September 2024, Lindo Offshore Renewables Centre (LORC) announced that the foundation for their new Main Bearing Test Facility (in Odense Harbour, Denmark) is laid and the facility is said to be operational by 2025. The total investment required for the facility is around USD 43 million, of which nearly USD 10 million is granted by the Danish government’s GreenLab program. The facility will allow the manufacturers to test the main shaft bearings used in 25MW wind turbines in isolation rather than as part of a complete powertrain.

What Type of Bearings Are Used?

Roller bearings and Slewing bearings are the primary bearings used in a wind turbine. A roller bearing is a type of bearing that uses different kinds of rollers (such as cylindrical, tapered and spherical) instead of balls to reduce friction. Spherical roller bearings and cylindrical bearings in conjunction with tapered bearings, are employed in parts like gearboxes, main shafts, and generators, as they can handle more thrust loads than other bearing types. A slewing bearing is a combination of an outer and inner ring, with either of them having a gear mechanism. Yaw and blade applications in a wind turbine use slewing bearings. Concerning the material type, metallic bearings capture around 85% of the market (mostly steel due to their offered strength and high resistance towards surface corrosion), with non-metallic and hybrid constituting the remaining 15%.

Growing Wind Energy Capacity: Boon for Bearings

Governments around the world strive to meet ambitious climate goals. For example, China pledges to grow its renewable energy capacity to 1,200 gigawatts, nearly double the existing capacity, by 2030, according to China’s 14th 5-year plan on renewable energy. Similarly, the European Union intends to scale their total wind energy capacity to 430 gigawatts by 2050, according to a report by the European Commission. Interestingly, the new capacity installed by the global wind energy industry reached a record 117 gigawatts (GW) in 2023—a 50% rise from 2022.

Apart from the sustainability goals, wind energy is proven to be cheaper than conventional fossil fuel-based energy production. For instance, the unsubsidised levelized cost of energy using coal in the US is USD 68-166, whereas that of the onshore wind energy is just USD 24-75. On the technological front, wind turbines have been growing in size. For example, hub height increased by around 29% and rotor diameter by around 40% in the US between 2013 and 2023, according to the Office of Energy Efficiency and Renewable Energy. The industry walked this path, as a larger rotor diameter allows the turbine to sweep more area, capture more wind, and produce better output efficiency. As a result of this, along with other technological advancements, the average capacity of newly installed wind turbines in the US was reported to be 3.4 megawatts, a whopping 375% increase since 1998-99. Moreover, the cost of onshore wind energy decreased by 68% and offshore by 59% between 2010 and 2022 on average globally.

This blend of climate goals and cost-effectiveness leads to increasing investments and expansion of global capacity for wind energy and proves to be the primary growth driver as it directly boosts the demand for wind turbine components, including bearings.

Current and the Future:

The global wind energy bearings market has seen continued growth in recent years. As a result, it reached USD 1.85 billion in market size in 2023 and is projected to hit USD 1.98 billion in 2024. Regionally, the Asia Pacific region dominates the market, led by countries like China, Japan, and India. The second largest region is Europe, driven by countries like Germany, Spain, and the UK. North America ranks third, led by the US, while the rest of the world contributes to the remaining market share.