Harnessing Wind Power with Roofy: a Horizontal Ridge-Mounted Rooftop Wind Turbine Prototype
Burger, Toni Alexander; Brisken, Daniel Andreas (2025)
2025
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Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi:amk-2025061122559
https://urn.fi/URN:NBN:fi:amk-2025061122559
Tiivistelmä
The concept of a ridge-mounted, horizontally aligned wind turbine called Roofy is based on the theory of wind acceleration at the roof ridge. It represents a form of renewable energy, whose significance continues to grow in response to climate change and the increasing global demand for sustainable energy sources. The design aims to efficiently utilize this natural effect while integrating seamlessly into the roof structure to improve acceptance in residential settings.
To investigate this, a small-scale prototype was constructed and tested. The prototype features interchangeable rotor types and incorporates a microcontroller-based measurement system. Initial performance analyses were conducted to compare different rotor configurations, including lift- and drag-based designs.
At a wind speed of 8.57 m s, the 7-blade lift-based rotor delivered the highest power output of 1.18 W, followed by the 5-blade rotor with 0.95 W and the 3-blade rotor with 0.58 W. In comparison, the drag-based Savonius rotor achieved a maximum output of 0.92 W. The highest overall system efficiency measured was 0.62%. The total cost for the prototype wind turbine, without an MPP tracker or any DC regulation, amounted to 144 €.
Compared to photovoltaics, which are equally well-established in the field of renewable energy, the specific power output of the small wind turbine is significantly lower at 11.93 W m² versus 216 W m², indicating a clear tendency toward limited viability of the Roofy concept in its current form.
Future work should include a detailed aerodynamic optimization of the multiblade rotor, the investigation of angled wind inflow to assess operational feasibility across various roof orientations, and a comprehensive on-site wind flow study to validate the assumed acceleration effects along the roof ridge.
To investigate this, a small-scale prototype was constructed and tested. The prototype features interchangeable rotor types and incorporates a microcontroller-based measurement system. Initial performance analyses were conducted to compare different rotor configurations, including lift- and drag-based designs.
At a wind speed of 8.57 m s, the 7-blade lift-based rotor delivered the highest power output of 1.18 W, followed by the 5-blade rotor with 0.95 W and the 3-blade rotor with 0.58 W. In comparison, the drag-based Savonius rotor achieved a maximum output of 0.92 W. The highest overall system efficiency measured was 0.62%. The total cost for the prototype wind turbine, without an MPP tracker or any DC regulation, amounted to 144 €.
Compared to photovoltaics, which are equally well-established in the field of renewable energy, the specific power output of the small wind turbine is significantly lower at 11.93 W m² versus 216 W m², indicating a clear tendency toward limited viability of the Roofy concept in its current form.
Future work should include a detailed aerodynamic optimization of the multiblade rotor, the investigation of angled wind inflow to assess operational feasibility across various roof orientations, and a comprehensive on-site wind flow study to validate the assumed acceleration effects along the roof ridge.