New Way Air Bearings ® remains committed to our goal of bringing the benefits of Porous Media™ air bearings to as many emerging markets as possible. Here, we want to highlight what our products can bring to the renewable energy sector. The renewable energy market—encompassing wind, solar, hydroelectric and nuclear—was valued at upwards of 768 billion dollars in 2021 with an expected compounded annual growth rate (CAGR) of 16.6% until 2030.
Suffice it to say this is a booming market. Any energy supplier would be wise to consider what other technology they can upgrade as they transition from fossil fuels to sustainable, renewable resources. This is where Porous Media bearings come in. Their unique mixture of self centering motion, frictionless operation, and operational longevity positions them as an ideal foundation for the next generation of renewable energy generation.
As of 2022, there are more than 70,800 wind turbines in the United States. With 14MW giants like General Electric’s Haliade X turbine coming to market, the appetite for wind power is clearly there. Yet, as the National Renewable Energy Laboratory points out, every new industry must overcome its reliability issues. Wind turbines are often plagued by gearbox failures, and in an industry survey of 37 incidents, 22 of these suffered bearing failures owing to wear, abrasion and cracking of the roller bearing races.
Porous Media air bearings very well may be the key to preventing these failures. As the NREL notes, many of these failures are not a result of the weight of gearbox components or anything unique to the operation of a wind turbine. Instead issues arise due to mundane tribological effects like abrasion owing to loose contaminants, which then enter the bearing lubricant and further abrade the bearing surface.
Air bearings provide motion by using a positively pressurized layer of air as the dynamic surface on which to move along. This means there is no contact between moving surfaces, and the air gap even acts to thermally dissipate heat. Our radial and balance bearings are already highly adept at supporting rotating artifacts, and their modular nature makes them scalable for small or large turbines.
Hydroelectric power is another valuable source for renewable energy, and similarly relies upon the simple but effective use of a turbine to power a dynamo. Owing to the massive power these turbines generate, they require complex motion solutions. A meta analysis of turbine bearing failure conducted by the Franklin Research Institute identified bearing system failure arising from numerous sources. Among them include excessively low/high oil pressure, excessive rotor vibration, contaminated oil, and excessively high axial displacement of the rotor.
For each of these modes of failure, air bearings offer passive benefits which work to ameliorate or outright remove these failure modes as a possibility. Starting with oil pressure, air bearings feature zero dynamic components and support a rotating artifact on a 5 micrometer thin layer of air. As such, the issues inherent to lubricant systems are eliminated.
Rotor vibration is also difficult to control in contact systems, and often requires soft mounts in an attempt to dampen resonant frequencies. As a direct result of the squeeze film effect on which our bearings operate, resonant and whirl frequencies are naturally damped below the thresholds which could cause mechanical damage. Similarly for axial displacement, the squeeze film effect causes air bearings to self center any rotating artifact about its true center of rotation
Tidal power is an emerging technology currently in its demonstration phase, using the variation in tides to turn underwater turbines for power generation. Unlike wind turbines and hydroelectric turbines, tidal turbines must contend with marine conditions, mainly corrosion and high fatigue on components resulting from water’s density. Moisture corrosion is already a danger for land based turbine systems, so this will assuredly also present a challenge for tidal power.
A fantastic answer to this challenge is New Way’s revolutionary New Seal ®. The product uses positive pressure to provide rotary motion and external sealing against fluid infiltration up to 35 psi. New Seal comes in double-faced, single-faced, and circumferential variations for every type of rotary motion application, and we already have a ready-made application form built for the specifics of New-Seal operation.
If you want to learn more about what porous media air bearings can offer to the next generation of renewable energy technology or you already have an application in mind, please contact us, and our dedicated engineering team will be in touch!