ONSHORE WIND POWER
An onshore wind turbine is, by definition, located on dry land. The horizontal axis wind turbines are now the most common form of terrestrial wind turbines.The machine usually consists of three adjustable blades carried by a rotor, itself attached to a nacelle that houses an electric generator. The whole is installed atop a high mast several tens of metres.
A 2 MW wind turbine measures 80 to 125 metres high on average and can weigh up to 300 tons.
A motor allows orienting the system rotor-nacelle of the wind turbine in order to place it upwind. The wind turns the blades (between 5 and 25 revolutions per minute) that drive the rotor and the generator that is integral with it.
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| Inside a wind turbine |
Two operating modes of onshore wind:
- Industrial use in the framework of a wind farm with a set of wind turbines grouped together on the same site, which is connected to the power grid.
- Domestic use under the "small wind energy" with wind turbines of smaller wingspan to meet the needs of individuals or small farmers.
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| Domestic wind turbine |
(see a movie: “What's inside a wind turbine”)
Other concepts onshore wind turbines:
There are other turbine concepts classified according to their axis
that are horizontal or vertical. However, they remain marginal and
restricted to specific contexts of use.
We can for example mention the vertical axis wind turbines of type "Darrieus" or even of type "Savonius". There are more suitable than the three-bladed wind turbines to architectural integration and to extreme conditions (wind speed greater than 100 km/h). However their performances are lower.
It is possible to install several « Savonius » wind turbines on a building roof without that they disrupt each other.
Stakes concerning energy:
Proven technology:
The onshore wind turbines are used for several decades. The feedback is substantial and the financial variables known.
Onshore wind turbines are less expensive to install and easier to maintain than offshore wind turbines, which must respond to the most important technical challenges related to marine environmental conditions. However, the potential yield is less important on land than far from shore because of the reduced speed and of the constancy of the wind.
New ways to optimize the resource:
The wind is variable and wind energy is therefore faced with intermittency problem of power generation. But it does not exist today an economically satisfactory solution to store electricity.
The generalisation of "smart grids" is a significant developing way for wind turbines integration in future power grids. These systems will allow responding to the challenges of tomorrow: better management of the flows, a better smoothing between electricity supply and demand, integration of new renewable energy sources and limitation of recourse to thermal power plants (currently used to cope with peaks of demand).
Return to "Wind power"
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| Savonius |
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| Darrieus |
We can for example mention the vertical axis wind turbines of type "Darrieus" or even of type "Savonius". There are more suitable than the three-bladed wind turbines to architectural integration and to extreme conditions (wind speed greater than 100 km/h). However their performances are lower.
It is possible to install several « Savonius » wind turbines on a building roof without that they disrupt each other.
See a movie: “Vertical wind turbines”
Stakes concerning energy:
Proven technology:
The onshore wind turbines are used for several decades. The feedback is substantial and the financial variables known.
Onshore wind turbines are less expensive to install and easier to maintain than offshore wind turbines, which must respond to the most important technical challenges related to marine environmental conditions. However, the potential yield is less important on land than far from shore because of the reduced speed and of the constancy of the wind.
New ways to optimize the resource:
The wind is variable and wind energy is therefore faced with intermittency problem of power generation. But it does not exist today an economically satisfactory solution to store electricity.
The generalisation of "smart grids" is a significant developing way for wind turbines integration in future power grids. These systems will allow responding to the challenges of tomorrow: better management of the flows, a better smoothing between electricity supply and demand, integration of new renewable energy sources and limitation of recourse to thermal power plants (currently used to cope with peaks of demand).
Return to "Wind power"
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