Onshore wind turbines operate in widely different climates. Seasonal weather, temperature fluctuations and periods of high humidity can create conditions for condensation inside towers, nacelles and electrical equipment.
The important question is therefore not simply whether a turbine is onshore, but whether the actual site conditions create a humidity-related reliability risk.
Cotes has more than 20 years of experience controlling humidity inside wind turbines, with dry-air solutions for protection throughout the turbine lifecycle — from transportation and storage to operation and retrofit.
Onshore turbines experience changing temperatures throughout the day, across seasons and between operating and standstill conditions.
As internal components cool, their surface temperature can fall below the dew point of the surrounding air. When this happens, condensation can form locally — including around sensitive electrical equipment.
Repeated moisture exposure can contribute to corrosion, reduced insulation resistance and electrical instability over time.
For coastal onshore turbines, airborne salt can further increase the risk by absorbing moisture and forming conductive films on contaminated surfaces.
The risk therefore depends on the actual climate experienced inside the turbine — not simply whether the asset is classified as onshore.
Once a humidity-related risk has been identified, the dry-air strategy should match the turbine and the problem.
Cotes Mobile Wind solutions use adsorption drying to remove water vapour from the air and lower the dew point. Depending on the turbine and identified risk, dry air can be used to stabilise the general internal climate or protect critical areas such as electrical equipment.
The same technology can also provide temporary dry-air protection during transportation, storage, installation, service and extended standstill.
For coastal and nearshore turbines exposed to significant airborne salt, the environmental conditions should be assessed separately to determine whether humidity control alone is sufficient or whether ingress also needs to be controlled.
