Prevention is cheaper than cure

If you own or work with wind turbines, you may have already asked, is the cost of installing a dehumidifier worth it? But one unplanned production stop can easily cost you 20.000 EUR per turbine.

It is difficult to predict how many times a turbine actually will break down or stop during its lifetime of 25-30 years, but humidity-related electrical failures occur in wind turbines if they are not protected. This has been documented several times, most recently in a study by Fraunhofer. At Cotes we have been involved in several projects where converter modules or transformers fail after just a few years in operation.

According to market research conducted by Cotes, just one onshore failure can easily cost 20.000 EUR. Offshore is more than twice as expensive when you include lost production and component replacement. Breakdowns are expensive. Over the lifetime of a project, just one annual electrical failure could cost more than 400.000 euros, if you add it all up.

Cost per failure per turbine 10 MW offshore 5 MW onshore

Minimum lost production time

48 hours

24 hours

Lost production costs

8,767 EUR

4,384 EUR
Component replacement

10,000 EUR

10,000 EUR

Installation/transport vessel

15,000 EUR

5,000 EUR 

Time to change/repair

48 hours

6 hours

Hourly rate technician 

110 EUR

80 EUR

Total cost per failure

45,287 EUR

20,344 EUR

Source: Cotes market research amongst turbines owners, OEMs and independent service providers. Calculations validated by industry experts.

Cotes works both with OEMs and turbine owners, as well as operators. Most commonly, we see problems with converters (IGBT modules), transformers, generators – to name just a few. Our clients typically contact us for retrofit purposes when they have a high degree of failure modes and production stops caused by humidity - which makes a strong case for protecting or extending the lifetime of your wind turbines with dehumidification. 

Humidity component failures like short circuits, arc flashes or breakdowns are caused by grid outage, curtailment (when you are forced to stop the turbine), local weather conditions, low wind time zones or turbine design. This cocktail of environmental and technical factors allows humidity to creep up well above the recommended limit of 60% RH, leading to condensation inside the turbine and issues with mould, corrosion and electrical faults.

To prevent this from happening, you need the right dry-air strategy. dehumidifier solution can either protect an entire tower and nacelle or specific cabinets or components inside a turbine. Cotes offers a wide range of different sized adsorption dehumidification solutions, starting at a few thousand euros.


In other words: If you avoid just one humidity related production stop over 25-30 years in your turbine, your investment in a dehumidification solution has already paid for itself.  

Get a Cotes dry-air solution recommendation

Ensure the longevity of your wind turbines with the right dry-air solution. If you don't give climatic conditions serious consideration, you risk condensation, leading to issues like mould, corrosion, and electrical failures. Installing a sound and robust dehumidification solution is a wise investment.

Could you benefit from consultation about the best dry-air strategy for your wind turbines? Our team of experts is here to help.