Dry-air solutions for

Wind Energy

Protect the inside of your wind turbine throughout the entire life cycle — onshore, nearshore or offshore.  

Humidity Related Issues in Wind Turbines

Exposed to the elements

Your wind turbines are exposed to the elements from the moment they leave the production floor. Whether your wind turbine is onshore, nearshore or offshore, you need a dry-air strategy to avoid mould, corrosion and electrical faults in your turbines.

The good news is that we can help you. With over 20 years of experience in the wind industry and working with some of the biggest names out there, we have helped them protect their assets and maximise the operational uptime of their turbines.

Wind turbine life cycle

What is your dry-air strategy?

The right way to dry your wind turbine depends on your specific dry-air strategy and how much consideration has been given to the issue of unwanted humidity. We provide different dry-air solutions from design collaboration through to retrofitting for extending end-of-life, reducing maintenance cost, avoiding wind turbine failure and wind turbine downtime—maximising uptime.


Integrated Design

Having a dry-air strategy for your wind turbine starts at the design process. Onshore and offshore turbines are designed with different locations and weather conditions in mind, yet they face similar challenges with mould, corrosion and electrical faults.

Effective, reliable control of corrosion means wind turbine manufacturers are able to work with lower ISO 9223 classification requirements and lower IP classes — which means lower costs for wind turbine materials, coatings and components. Cotes technology and know-how enable you to roll back key manufacturing costs by as much as 10–30% because standard-spec coatings, parts and fittings are sufficient.

GE Haliade-X


The nacelles, hubs and towers of wind turbines – and all the sensitive equipment and electronics inside them – are exposed to tough conditions from the moment they leave the factory all the way to the site. Some turbines are in transit for months on end before becoming operational.

Cotes dehumidifiers keep nacelles and towers — and the expensive fixtures inside them — in ready-for-service condition while en route to the site. This provides big savings on commissioning as well as rolling back maintenance and service costs — and keeps up the in-service revenue stream.

Lightweight CR240 dehumidifier


© Vestas Turbine Parts at Able Seaton Port’s Installation Base for the 857MW Triton Knoll Offshore Wind Farm

En route to the wind farm site, towers and nacelles are often stored out in the open on trucks, rail cars, ship decks, storage areas and quaysides, exposed to fluctuating temperatures and weather conditions for extended periods of time. Cotes dehumidifiers can help you protect these assists even before they become operational.

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Offshore Foundation

In the case of offshore wind turbine installation, the foundations of these turbines can be installed for many months, even years before the turbine arrives on site. This leaves the foundation and electrical equipment exposed to moist and salt-laden air. 

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Operation and Maintenance (Retrofit)

Conditions don’t get easier once the nacelles and towers are erected on-site and become operational. Nearshore and offshore wind turbines (offshore in particular) are exposed to harsh weather conditions and the corrosive combinations of airborne humidity and salts 365 days a year, for the entire duration of their service lives, can have a detrimental impact to the turbine's profitability if there isn't an effective dry-air strategy in place.

RWE retrofits wind turbines


A good dry-air strategy does not stop at the wind turbine. The substations that gather the power from the wind farm and connects it to the grid are also vulnerable to the elements. These substations are full of sensitive electrical equipment that need to be protected from corrosion and mould and if they shut down due to electrical faults, it means the whole wind farm becomes nonoperational. Some substations are required to be operational without servicing or maintenance for up to 12 months at a time which makes having an effective dry-air strategy crucial. 

Overpressure dehumidification systems

Find the right dry-air solutions for your offshore assets

20210615 Productimage_Wind_Lineup_Steel overlay-min-1


issue with humidity

Airborne moisture causes problems

Airborne moisture is one of the major sources of operating disruption, damage to equipment and structures, and costly practical problems inside the nacelles and towers of wind turbines — especially those offshore. To our knowledge, as much as 20–25% of all breakdowns in offshore wind turbines are caused — directly or indirectly — by moisture and corrosion.

Such airborne moisture combines with acidic salts in the air to cause corrosion and condensation inside the wind turbine, as well as giving rise to bacterial growth, mould problems and a risky working environment. Together, these result in a wide range of mechanical and electronic problems, as well as causing electrical glitches and expensive unscheduled downtime.