German wind developer Schierloh Engineering has completed a trial of a new noise-reduction blade retrofit on an Enercon E-160 E3 turbine, reporting measurable sound reductions that could support broader deployment across noise-constrained sites.
The trial, conducted near Haemelhausen, involved replacing the turbine’s original blade serrations with FeatherEdge, a retrofit developed by Canadian firm Biome Renewables. The modification was installed in February 2025, with noise measurements carried out in March and April by T&H Ingenieure in line with IEC standards.
According to Biome, the retrofit resulted in a sound power level reduction of 2.1 decibels A-weighted (dB(A)) during standard operation. Additional reductions were recorded across all six noise-reduced operating modes, with no tonal noise observed during testing.
“At residential locations, we recorded low-frequency reductions of nearly 3dB(A),” said Soehnke Schierloh, chief executive of Schierloh Engineering. “We already plan to outfit additional turbines which are currently running under heavy noise curtailments.”
The FeatherEdge design is TÜV-NORD certified and differs from traditional sawtooth serrations through its longer, more flexible structure, inspired by the shape of a snake’s tongue. The company says this geometry improves both noise suppression and turbine performance.
“With three very successful applications, we’re now scaling up commercial sales and talking with OEMs about making FeatherEdge a factory option,” said Ryan Church, Biome Renewables’ founder and chief executive.
Previous field tests have been conducted on a 3MW turbine in France and a Senvion MM92 in Canada. The latest trial marks the first application of the technology on Enercon hardware.
Biome Renewables said the retrofit could allow turbines to operate in more productive modes without exceeding regulatory noise limits, potentially unlocking generation capacity currently restricted by curtailment rules. The company is offering the technology to turbine owners for both individual machines and full wind farm retrofits.
