From surging material and logistics costs to rising maintenance expenses, the financial model for wind energy is under strain, with a range of factors governing its economics. And the timing couldn’t be more critical; today, wind operators are under increasing pressure to deliver higher availability rates at lower cost, even as inflation, tariffs, and supply bottlenecks escalate component prices.

The operations and maintenance (O&M) value chain, in particular, is creating a number of specific challenges for operators. According to GlobalData’s Wind Turbines Market report, maintenance and service currently account for up to 25% of total lifetime expenditure for wind projects.

For example, the average cost to replace a gearbox – which commands a high repair cost alongside a relatively high failure rate – can easily reach six figures if repairs are no longer covered by warranty. Arguably the most important part of the turbine, the internal gearbox is a complex system that typically requires the most attention. Though they are built to last around 25 years, temperature fluctuations and load changes can cause the gearbox to crack and fracture, leading to parts needing to be replaced or total gearbox failure.

This growing need for cost-effective O&M solutions has spurred an industry-wide focus on smarter strategies and technologies that can help to expand asset lifespans, reduce downtime, and lower the cost of operations and maintenance without compromising on performance. GlobalData’s Renewable Energy 2025 report highlights that the path forward depends on an “integrated effort” between OEMs, developers, and policymakers to ensure energy transition targets remain viable amid economic headwinds.

Why are turbine O&M costs rising?

Several factors are contributing to the rising costs of raw materials, including the lingering impact of the Russia–Ukraine conflict, as well as tariffs and trade restrictions in major markets such as the US, which have compounded the strain.

Once turbines are installed, operators’ greatest ongoing expense relates to keeping them spinning efficiently, particularly the costs of servicing gearboxes and replacing lubricants. According to Mike Blumenfeld, industrial lubricant development and wind energy specialist at ExxonMobil: “When you operate wind turbines, you make a massive upfront investment. Once they’re in place, the main variable affecting profitability is O&M, and a huge portion of that comes from sending technicians up-tower for repairs, service, and especially oil changes”.

To add further strain, even the simplest maintenance task can spiral if complicated by logistics, particularly offshore. Blumenfeld gives an example: “I once attended a gearbox inspection in Canada. We lost three days waiting out icing conditions. Then a technician dropped a wrench into the gearbox, and that single incident took the turbine offline for hours.”

Each intervention comes with several expenses, including technician labour, safety equipment, chartered vessels or cranes, and lost production revenue while the turbine is offline. By reducing the need for maintenance and limiting interventions, operators could drastically reduce expenses.

Navigating spiralling O&M costs in wind turbines

One countermeasure to rising O&M costs is the shift towards larger turbines.

The size of wind turbines has been consistently growing as developers and manufacturers strive to enhance efficiency and reduce the cost of energy production. Contemporary onshore wind turbines are frequently installed with hub heights surpassing 90 meters and rotor diameters greater than 120 meters. These dimensions enable turbines to access stronger and steadier winds at elevated altitudes, leading to increased electricity generation per unit.

Consequently, fewer turbines are required for expansive projects, which improves the overall economics of these endeavours. The offshore wind sector is advancing this progression, with some manufacturers even exploring prototypes exceeding 15MW, which have the potential to supply electricity to thousands of homes from a single turbine. The shift towards larger turbines not only boosts efficiency but also diminishes installation and maintenance expenses per megawatt.

This trend towards larger turbines not only lowers the cost per megawatt-hour but also optimises the use of space, both onshore and offshore. With fewer turbines required for the same power output, concerns about land use and visual impact for onshore projects are mitigated and, at the same time, construction and maintenance costs can be reduced for offshore ventures.

Designing for longevity

Another key measure to navigating surging O&M costs is to review your oil strategy. Historically, gearbox oils had to be changed approximately every three to five years. As turbines scaled up, synthetics replaced mineral oils for their longer lifespans and tolerance to heavy loads, but even these synthetics required regular change-outs.

ExxonMobil recognised that operators needed a solution that didn’t require frequent replacements. Consequently, its Mobil SHC Gear 320WP has been engineered to last the full design life of the gearbox, known as a “fill-for-life” (FFL) solution*. “We learned a lot from our earlier 320WT product, which carried a seven-year warranty, later extended to ten,” explains Blumenfeld. “With 320WP, we specifically designed for longevity. It’s highly filterable, so contamination – one of the main reasons for oil changes – can be removed efficiently, and its additive system can be topped up to restore balance over time.”

The base oil used in turbines barely oxidises due to relatively low operating temperatures. ExxonMobil focused on additive stability and top-treat chemistry, a system of replenishing only the additives that degrade, helping to keep the lubricant balanced indefinitely*.

For OEMs, FFL technology helps to cut direct maintenance costs by removing oil change cycles but, just as importantly, it significantly reduces downtime risk. “It can mean no large-volume oil disposal, no transport of new oil drums, no service crews for changes, no offshore logistics headaches,”* Blumenfeld adds.

Looking forward with fill-for-life

Fill-for-life lubricants won’t single-handedly solve the cost crisis in wind energy, but they are a prime example of the innovation needed to stabilise the sector. For operators, they help to remove one of the most expensive and unpredictable maintenance variables. For OEMs, they can offer a performance differentiator in an increasingly competitive landscape.

Blumenfeld summarises: “What operators want most is peace of mind, knowing their turbines will run reliably without surprise maintenance bills. Fill-for-life gives them that assurance.”

In a market defined by volatility, that peace of mind is a valuable commodity. To find out more about Mobil SHC Gear 320WP, including the science and extensive testing behind its development, download the whitepaper below.

*Follow OEM recommendations.