How do you make money with CMS?

Key information and case study below!

The availability and the consequent O&M costs of wind farms are influenced by the failure and downtime of wind turbine components.

In an industry that requires maximum uptime to generate profitability, it is easy to see how downtime can mean the difference between success and failure. Turbulent wind conditions subject turbines to damaging structural vibration levels and peak load stresses on drivetrains, gearboxes, and generators. If left unchecked for extended time periods, it may cause consequent failures of other components and even the entire WT system.

Wind turbine failures are equivalent to crucial financial losses. Therefore, “Future R&D should focus on minimizing and, if possible, even elimination of unexpected failures. In other words, the wind industry should move away from corrective maintenance (remedying of failures) and more towards preventive, predictive maintenance (repair just before failure) in order to achieve maximum availability.” Source: EAWE, European Academy of Wind Energy. 2016

Revenue and costs makes up the profit for a wind farm. The Turbines has to be available to generate when there is wind and all O&M activities should be planned around this availability. Subsequently, it is important to understand the factors affecting the turbines availability, and manage them effectively with minimum safety and financial risks.

A wind turbine condition monitoring system (CMS) provides diagnostic information on the health condition of various components and subsystems and, therefore, allows maintenance to be scheduled before a failure or a critical malfunction occurs. Through CMS, fault diagnosis is performed to detect, locate, and identify occurring faults and monitor and predict the development of the faults.

Gram & Juhl is watching your wind turbines so you can protect your assets and optimize cost of energy.

On any given day, 24 hours a day, Gram & Juhl are monitoring wind turbines globally through its state-of-the-art Turbine Condition Monitoring (TCM®) system, diagnosing failures and providing prognostic information and recommended actions to wind farm sites. It also includes a time for reaction, letting you know how far you can stretch before taking action, and this way maybe combine the action on one turbine with another turbine, saving repair costs in the process. “TCM® provided us with an extra pair of eyes. Without TCM®, we would have had to replace a costly gearbox.” – Jon Pedersen: Site Manager for Rødsand II Wind Farm

Knowledge and experience from more than 17,000 wind turbines are embedded in the TCM® technology when it comes to hardware, software and services. With TCM®, you receive a proactive maintenance plan that will help you secure your wind assets well into the future. The result is optimized cost of energy. “Pattern Energy sees tremendous value in vibration monitoring technology for long-term O&M strategy, and Gram & Juhl provides proven hardware, software, and monitoring experience. With active vibration monitoring in place, Gram & Juhl is helping us improve our predictive maintenance capabilities. We are encouraged by the results that we are seeing after only 6 months with the system installed.” – Ben Rice, Manager Operations Engineering.

THE BOTTOM LINE: Gearbox is considered the most troublesome subsystem in WTs as gearbox failures contribute to approximately 20% of the downtime of WTs. Replacing a damaged gearbox can cost approximately between $522,000 and $609,000 including associated crane hire, loss of revenue due to downtime and labor costs. The TCM® system are able to identify early bearing and gear failures that can result in cost savings for the operator of over 90% per event.

Even though there are a huge savings potential with TCM®, for some reason the focus is more on service contracts. Nevertheless, why not let the numbers speak for themselves. Over a period of 15 years the costs for TCM® is less than 1% of the total investment for a wind turbine while service contracts make out easily 40%.

“Every turbine has its own challenges and failure rates. Doing monitoring now over 10 years I can say, you never know when your turbine will have an issue. Therefore an O&M strategy relying just on yearly or half year inspections and one time measuring campaigns is a kind of flying blindly. Apart from preventing from catastrophic failures CMS can help to keep turbines in right operational conditions what we have seen several times e.g. after service was performed”. Source: Zabihulllah Alefi, COO, Leader of Condition Monitoring Division, Gram & Juhl.

Real life example – Fault Detected With TCM®

In 2016, the TCM® system caught a fault on a HS pinion tooth, which could have damaged other teeth or in worst case damaged the gearbox. This failure could have led to a severe failure with the cost of approximately $420,000 had it not been caught in time. However, through TCM® Monitoring the failure was caught in an early stage, making it possible for the customer to repair and replace up tower, eliminating crane cost and cutting down the loss of revenue. The pinion shaft was exchange, without no collateral damage, and for the cost of $36,000. The TCM® Monitoring system thereby saved the company a total of $384,000 and a percentage of 91.43 % for this single incident.

Facts about Gram & Juhl:

Gram & Juhl A/S was founded in 1997 by Axel Juhl and Klaus Gram-Hansen. Gram & Juhl A/S is a leading supplier of CMS to the wind industry. The company has sold over 17,000 Turbine Condition Monitoring Systems (TCM)® worldwide. The TCM® solution empowers customers to protect their assets and plan an optimal maintenance, thereby driving LCOE down. Gram & Juhl is a modern, internationally-oriented company, that has grown rapidly during the past years.

The company first threw itself into a foreign market in 2015 by opening an office in Denver, Colorado, USA – Gram & Juhl North America Inc. and has now more than 6,500 TCM® installations in the US. TCM® is a registered trademark of Gram & Juhl A/S. Learn more at

In addition to the North American office, the company recently opened a monitoring department in Oldenburg, Germany.

For more information visit or contact their team directly at