The WindWhisperer 100 Max generates approximately ~230 MWh per year. The WindWhisperer 50 generates approximately ~115 MWh per year. But those figures are conservative averages — your actual output depends on where you install the turbine and how you configure it.
This page explains what those variables are, how to estimate output for your specific site, and what the numbers mean in practice.
Wind energy is proportional to the cube of wind speed. This means small differences in average wind speed create large differences in annual output.
A site with a mean wind speed of 6.5 m/s will produce roughly three times more energy than a site with 5.0 m/s. A site with 7.5 m/s will produce roughly twice as much as one with 6.5 m/s. This exponential relationship is why wind resource assessment is the first step in any serious wind installation evaluation.
In the UK and Scandinavia, mean wind speeds vary from around 4.5 m/s in sheltered lowland areas to 8.0–9.5 m/s in exposed coastal locations, upland sites, and open moorland. Your location matters enormously.
Wind speed increases with height above ground level. The relationship is not linear — it follows a power law relationship that varies by local terrain. In general, turbines at height have access to faster, more consistent wind, and thus generate more energy.
For rooftop installations, the roof height determines turbine elevation. Commercial roofs typically sit at 5–15 metres; industrial buildings may be 10–25 metres or higher. For ground-level mast installations, raising the turbine height from 10 to 20 metres typically increases wind speed by 20–30 percent, and annual output by roughly 60–100 percent.
The WindWhisperer 100 Max is offered in two rotor heights: the standard height and the tall-rotor WindWhisperer 100 Max, which places the rotor centre at 4.4 metres. Where building or mast height permits, the taller installation captures more energy.
Wind directors are vertical panels (typically 4–5) mounted radially around the turbine stator, each as tall as the rotor and extending 2–5 metres outward. They work like a funnel, channelling a wider column of air into the rotor and lowering the effective cut-in speed.
The WindWhisperer 100 Ultra with wind directors typically produces ~439 MWh per year — substantially higher than the base WindWhisperer 100 Max at ~230 MWh. The 50 kW platform shows similar benefits: WindWhisperer 50 Ultra at ~220 MWh versus base WindWhisperer 50 at ~115 MWh.
Wind directors are a physical structural addition, not a software feature, and they require structural assessment and planning approval. They are most practical on ground-mounted installations and larger commercial roofs. For rooftop installations on smaller buildings or sites with spatial constraints, the standard configuration without directors is often the right choice.
HNordic and your certified installer use several methods to estimate output for your specific site:
Wind data mapping. Meteorological databases and wind resource maps provide mean wind speed estimates for your location and elevation. In the UK, the Department of Energy Security and Net Zero publishes wind speed mapping; in Sweden, SMHI (Swedish Meteorological and Hydrological Institute) maintains comparable data.
Site-specific terrain analysis. Local obstructions — buildings, trees, topography — reduce wind speed through friction and turbulence. An assessment evaluates how your specific installation location sits relative to nearby features.
Wind direction distribution. VAWTs perform well across all wind directions, but sites with strong prevailing winds in one or two directions may perform better than sites with highly scattered wind directions.
Historical performance data. If neighbouring sites have existing renewable generation, actual output data is more reliable than modelling alone.
These inputs produce a power curve specific to your site — a table or graph showing expected output at each wind speed. From the power curve, annual output is calculated by weighting each wind speed by its typical frequency at your site.
~230 MWh at a typical good-wind site is roughly equivalent to the annual electricity consumption of:
For businesses currently paying electricity bills of £30,000–£50,000 per year (or equivalent in SEK), a WindWhisperer 100 Max installation at a good-wind site will typically displace 40–60 percent of annual consumption, with the remainder drawn from the grid or supplied by battery storage during calm periods.
The WindWhisperer 50 at ~115 MWh suits smaller properties — retail units, small offices, modest farms — consuming roughly 100–150 MWh annually.
Every HNordic installation includes integrated battery storage as standard — 430 kWh LFP for the 100 kW platform, 215 kWh LFP for the 50 kW platform. The battery does not increase annual energy generation, but it changes when that energy is available.
During peak wind periods, surplus generation charges the battery. During calm periods, the battery supplies load. This smoothing effect is particularly valuable in Northern Europe, where wind patterns have seasonal variation — stronger winter wind, calmer summers. The battery bridges those gaps and allows you to capture and use wind energy that would otherwise be exported to the grid at lower tariff rates.
Ask a question to begin a site assessment with HNordic and a certified installer in your region.
See also: What wind speed does a vertical axis wind turbine need? · What is the payback period for a wind turbine?
Tell us your location and annual electricity consumption, and we will calculate expected output for your site.
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