Siemens 4MW spearheads platform strategy

Germany’s Siemens will today launch its recently unveiled 4MW wind turbine, the SWT-4.0-130, as the flagship in a “platform” strategy aimed at standardising its machines in four main groups for mass production.

The new model, which features ultra-flexible 63-metre blades, will target the “comfort zone” offshore projects — developments in depths of up to 30 metres and less than 30km from shore — using a design built around the company’s workhorse SWT-3.6-120.

Nacelle and tower are “advanced variants” of the 3.6MW turbine — 500 of which have been erected around the globe, with another 1,200 on order — while the drivetrain is an evolved version of its predecessor’s three-stage, geared concept, powering an asynchronous generator.

The aeroelastic B63 blades, said to be the “longest and most technologically advanced” in the 4MW class, have been developed through an “optimised coupling of bending and twisting”, making them respond better to high wind loads by cushioning forces, like “shock absorbers on cars”, says Siemens.

The blades will be fabricated using the company’s “no-glue joints” IntegralBlade process.

“The advancements designed into the SWT-4.0-130 increase energy capture by up to 15% over our best-selling SWT-3.6-120 type,” states Siemens Wind chief technology officer Henrik Stiesdal.

The prototype of the 4MW machine has been showing “excellent performance” in trials at the Østerild test centre in Denmark since installation last December, he notes.

Siemens expects to put the new turbine in the showroom next year with serial production slated for 2015.

The platform design strategy will tear a page from the automotive industry’s manufacturing practice of mass-produced modular components.

All future Siemens wind turbines will be “bundled” by product platforms G2, G4, D3 or D6, with the G denoting “geared drive” and the D “direct-drive”.

“We can reduce production and logistics cost by standardising and modularising components within our product platforms,” says Stiesdal. “This is a major step towards achieving our goal of making wind power independent from subsidies.”

IHS Energy estimates that shallow-water wind farms currently account for 93% of European and nearly 100% of Asian capacity.