In order to compare this innovation to traditional wind power generators, Vergnet’s model GEV HP 1Mw was chosen and official data published by that company was examined.

Model GEV HP 1Mw is a two blade generator, the rotor has a diameter of 62 metres and is positioned at a height of 70 metres on a tube-shaped tower. Its peak power is 1Mw and its market value is 1.750.000 Euro.

This comparison is carried out against a TWIND generator (see bottom page for picture) composed by two aerostatic balloons with a diameter of 12 metres working at an altitude of 1000 metres, each equipped with two sail surfaces (parachutes) of a diameter of 19 metres. The TWIND generator’s energy yield was calculated by a process that can be viewed here.

In confronting the two technologies, 3000 hours a year of wind presence were considered for the traditional generator and a corresponding 6900 at an altitude. Wind velocity at high altitudes was increased by applying to the empirical law of power a cautionary factor of 0.20.

The graph reveals how the two generators have a practically equivalent energetic yield at a low altitude wind velocity of 8 metres per second and how TWIND technology shows improved performance with superior wind velocity.

 

The next table shows the comparison of indicative component cost between the two systems. Data regarding the traditional generator were considered at an installed power of 1000 Kwp in the study: Wind Turbine Design  Cost and Scaling Model – L. Fingersh, M. Hand, and A. Laxson, NREL, 12/2006; The costs for the TWIND system were calculated using supplier cost estimates.

The comparison shows that, at an essential equal performance, TWIND technology offers savings up to 60%. Implementation of a traditional wind power generator requires then an investment 150% larger compared to an equivalent TWIND generator.

 

The comparison between TWIND and all existing technologies that are attempting to take hold in the field of wind power generation will reveal three essential differences:

 

 

 

 

 

 

The first differentiating element is the functioning reliability derived by the presence of a single connecting cable (which avoids the risk of cable tangling) and by a mechanism which does not require complex operational systems to operate and is based on the simple laws of physics.

Second, the positioning of the electrical generator on the ground and utilizing floating sail surfaces, allows for the implementation of high power yield equipment which is impossible in systems in which the generator is carried to the operational altitude; such generators are naturally limited by their weight and their power output.

Thirdly, the installation of a TWIND generator has a low environmental impact due to the reduced size of the ground structure necessary to house the electrical generator and the connecting cable anchoring point. Such a reduced structure has virtually no impact on cultivations or the surrounding area.

The module has virtually no impact on the appearance of the landscape. The apparent size of an object is perceived by the human eye based on its size (D) and its distance (d). This apparent size is given by the angle (measured in RAD) which is calculated by the equation D/d multiplied by 360/2π.

Taking into consideration an aerostatic balloon of 12 metres in diameter, the angle at which the parachute (19 metres in diameter at an altitude of 1000 metres) is visible is equal to 1.1 RAD. To have a clear idea of the visual impact, we can imagine a 1 Euro coin (23 mm in diameter) placed at a distance of 1.2 metres (0.023 divided by 1.1, multiplied by 360/2π).

The apparent size is perceived by a viewer, placed on the ground and perpendicular to the object, at the point closest to him/her. Naturally as the distance is increased, visibility of the object becomes impossible to the naked eye. If we consider a viewer standing at a distance of 5 Km from the installation, the visual perception will be equivalent to a 1 Euro coin placed at a distance of 6 metres.

These three characteristics, summed together, determine high energetic yields with low environmental, installation and maintenance costs which make this technology efficient for industrial use.