Knowledge Center

Five reasons for wind energy providers to invest in transformer monitoring

3rd April 2023

A key asset within an offshore and onshore wind farm is the power transformer which connects the wind energy to the electricity grid. Power transformers should have a design life at least as long as the typical 25-year life of a wind farm. However, transformers can develop faults well before the end of their life expectancy, leading to failure and downtime for the wind farm.

Condition monitoring can provide immediate insight into both the health of transformers and the risk to availability. By continuously monitoring each transformer, emerging faults are identified immediately in real-time, enabling interventions to minimize the potential risk of downtime for the wind farm’s facilities.

Here, we outline five reasons why wind farm owners and operators should invest and implement transformer monitoring to protect their investments and optimize their operations.

1. Maximize availability and reduce risks

Uptime is a top priority for onshore and offshore wind farm owners or operators and many consider the power transformer as the single point of failure for any plant. If a transformer suffers a critical failure, this leads to potential loss of the entire generation capacity of a wind farm and revenues. It's therefore important to have solutions in place to monitor crucial assets like power transformers and implement condition-based and preventative maintenance programs to reduce the risk of unscheduled downtime. Outages mean loss of not only revenues, but also reduction in power supply from wind generation and, in some cases, potentially the need to back up with fossil-powered generation. This can have a significant impact on an operator’s targets for energy generated.

Finally, insurance premiums are a significant cost, especially for offshore installations. With insurers increasingly demanding that best practices in asset management are implemented, monitoring transformers can help wind farm owners or operators manage their insurance costs. Implementing a monitoring solution provides better information on the health of the asset being insured and enables preventative maintenance to be undertaken before faults develop to a point of catastrophic failure, therefore reducing the risk to insurers.

2. Increased visibility of asset condition and reduced maintenance costs

Without visibility of assets and their performance, onshore and offshore farm owners and operators can only be reactive to issues as they arise, resulting in expensive operational costs and interrupted service delivery. By installing a powerful transformer monitoring system, a real-time view and a pre-emptive approach to maintenance and repairs can be achieved. For best results, the monitoring solution implemented should be holistic: this will give the Asset Manager a complete view of the conditions of each component of the power transformer, covering most of the possible failure modes through dedicated sensors, advanced analytics and diagnostic tools.

With many onshore and offshore sites often in remote and unmanned locations, visiting an offshore or onshore wind farm for maintenance or data gathering can be costly and time-consuming. Online transformer monitoring solutions have advanced communication and alarm capabilities which alert Operations Managers to any potential faults before they become serious. This helps to prioritize and plan interventions and maintenance, reducing the need for unplanned site visits and their associated costs.

Offshore Wind Facility

3. Asset digitalization and the importance of data-driven decision making

With the increasing complexity of onshore and offshore wind farms, it’s not always possible to have a subject matter expert for each individual component within the organization. Today transformer experts, in particular, are becoming less common which means it's important to make good use of real-time data from sensors deployed in the field and other available data such as the asset’s age, location, off-line tests etc.

Transformer condition monitoring solutions can produce an overwhelming amount of data, making an Asset Manager’s job even more challenging. That’s why any transformer condition monitoring solution should be accompanied by advanced data solutions and digital expert services, which provide Operations Managers with data-driven insights and support to help them make more informed decisions. Advanced analytics, software tools and dedicated digital consultancy services can help wind farm operators to manage their transformer fleet more effectively. This can also be supported with insights and prescriptive actions which offer a more realistic view of each asset’s health, plan maintenance activities and determine the impact it has on safety, reliability, and risk to the company’s revenue.

4. Reducing the risk of downtime and plant failure

Although power transformers are static machines with a relatively simple working principle, they are complex assets, made up of several materials, such as copper, iron, solid and liquid insulating materials like paper, wood, porcelain, resin, and oil. These are prone to different failure modes that can affect the main tank, bushings, tap changer, oil conservator, cooling system, etc. Combining these elements and ensuring that they endure for their entire design life is not an easy task. As power transformers are subject to multiple and combined types of stress: electrical, thermal, mechanical, environmental, and even chemical, the risk of failure with these elements can be high.

Furthermore, by its nature wind generation is intermittent, which places additional stress on transformers. Therefore, only well operated and well managed transformers usually reach the end of their expected lifespan without major issues.

Transformer Onshore Wind

5. Avoiding premature transformer replacement and consequential loss of revenues

If a power transformer fails and needs to be replaced, the costs include not only those of the asset but also the loss of revenues and possible collateral damages that a catastrophic fault of a high voltage asset may cause. Rising global demand for power transformers rising and current supply chain challenges can mean a long wait for a replacement. The specification, purchase, delivery, and installation of a new transformer to replace a failed one involves several people and entities both internally and externally and can take several months, during which time power is not being generated. Even in cases where a spare transformer is held in stock, the remote location of many renewable installations means it can take several weeks with oversize load cranes, and specialists needed to carry out the replacement.


With critical assets experiencing more variable load patterns due to an increased output of wind energy, it's important for owners and operators of wind farms to gain a better understanding of key assets.

Power transformers are one the most critical and complex components on an onshore / offshore wind farm and they are prone to different kinds of faults and technical issues. Few operators have in-house expertise on specific critical assets such as power transformers and so it can be challenging to optimize the performance of these key assets and extend their lifespan.

By investing in an end-to-end transformer condition monitoring solution, Asset Managers can gain increased visibility and insight into the health, risk and performance of transformers. Armed with this knowledge, wind farm owners can gain a better understanding of the potential risks to availability and consequently risks to revenue. Faults can be identified in real-time, enabling interventions to be taken to minimize the potential risk of downtime and proactive maintenance strategies can be put in place. By being better equipped with more appropriate data and insights on their critical assets, wind farm owners and operators can make more informed decisions.

Contact us to find out how we can partner with you to safeguard your supply of wind power to the electricity grid.

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