The story behind SWP-25kW

Back in 1988, Robert Sørensen came up with the Bosted 22 wind turbine. It was 22 kW and designed as a pioneering horizontal wind turbine.

Robert had great knowledge of wind power technology and thorough familiarity with, among others, the Kuriant wind turbine. His strategy was to build a stable and reliable wind turbine, which could demonstrate a long life cycle. Robert succeeded in doing that – the Bosted 22 wind turbine ran for 19 years without major repairs.

When the wind turbine was taken down in 2008, it was because the adjacent town zone was expanded, and thus the license for his wind turbine could not be upheld. At that time, the wind turbine was still fully functional – among other things, the gear, main bearings, yaw system and braking unit were still the original components, which obviously never had been needed to get changed.

It is with the starting point in the Bosted 22 wind turbine’s basic structure and Ringkøbing Maskinværksted’s (now Solid production’s) 20 years of experience in the wind power industry that we have designed the SWP 25-14.

How does the SWP-25kW function today?

We have retained identical main components as well as the fundamental concept of Robert’s wind turbine – though we have chosen to upgrade with one additional generator. Thus, the SWP 25-14 has both a main generator and a light wind generator. This means that SWP 25-14 can produce considerable amounts of electricity even from 3 m/s (see the wind turbine’s effectiveness curve).

The wind turbine’s high total annual electricity production is achieved particularly because of our very own designed and produced blades.

It was with a view to maximizing annual electricity production from our wind turbines that we developed the new 14 m rotor dedicated to SWP 25-14.

The development work has thus had a focus on producing a modern blade with high output especially at lower wind speeds (4-8 m/s).The blade, which we designate as RMV 7000 TB (Tip Brakes in the blades) and produce at our own factory, meets these requirements without compromising on noise or long life cycle. This is possible because we use the latest new design technologies and tools.

A noiselessy turbine

Besides making sure the wind turbine will produce the most electricity possible, the other big challenge is doing this as noiselessly as possible. Thus, we at Solid Wind Power are most satisfied in being able to point out that SWP 25-14 is likely the market’s least noisy small wind turbine. Again, this is possible due to our own RMV 7000 TB blade and the light wind generator, which by way of a gearing via a belt drive allows us to run the wind turbine with only 38 rotations under 5 m/s. The low rotations make the blades almost silent at low wind speeds and, at the same time, give the wind turbine a tranquil image.

But it’s not only the blade we’ve worked on to make noiseless. The low noise level is also due to the way we have constructed the nacelle. It is divided in two – a top frame and a base frame, which makes it possible to isolate the rotating parts from the rest of the construction via vibration dampers.

We have been able to hold the weight of the whole nacelle to a minimum by optimising the construction with the help of computer-based load simulation (technical term: Finite Element Analysis).

In the design of the exterior of our small wind turbine, which in all modesty even we think we have succeeded with, we have placed great emphasis on aesthetics – you have to remember that a wind turbine becomes someone’s closest neighbour for more than 20 years.

We have chosen to call our wind turbine Solid Wind Power, as we believe it is a solid wind turbine that is designed for many years of reliable and effective electricity production.