Siting & Planning

How much space do you need for a turbine?

You will need a land area at least 2.5 times the height of the mast, with a width at least 2 metres wider than the rotor. Guyed towers require more space. You will also need to take into consideration space for lorry access and for servicing which will usually require space to lower the mast. The power available to a turbine is related to the wind speed cubed - so even a small increase in wind can give a large increase in output. Siting your turbine is dependent on your location and local planning requirements.

How far away from the nearest building should it be sited?

Turbines should be sited at least 20m away from a building. The further away the larger the cable requirements. Turbulence generated by buildings and other obstructions reduces power output and also increases wear and tear on the turbine. Siting your Turbine

When choosing a location to install the turbine it is important to put it as high up as possible on the prevailing wind side of your property.

• The distance from the turbine to the grid connection should be reasonably short to minimize power loss over lengthy cables.
• You need an area of clear ground at least 5m x 5m available ideally on the windward side of your property.
• Once you have identified the best location, you need to ensure that you have reasonable access for lowering (hydraulic tower) or crane use (fixed tower). Locations that are hard to access can often incur extra cost for the hire of specialist access equipment.
• You also need to consider where to put the electronic control system. The electronic control system and inverters will be situated inside your building. For outdoor installations the use of a IP65 rated enclosure will be required.
• The electronic control system needs to be connected to both the wind turbine and the distribution board of your electricity supply.

What about the Base?

It is important to determine that the site base will be structurally suitable for the installation of a turbine. During the site assessment, we will assess the structural suitability of the proposed site.

As a rule of thumb the following issues need to be considered:

• Depth of soil for excavation
• Area available
• Routing of cables
• Housing of control equipment
• Proximity to neighbouring property

What wind speed should I expect?

Before you install a wind system it is essential you have a good knowledge of wind speed at your site. The Department of Trade and Industry wind speed database contains estimates of the annual mean wind speed throughout the UK. The details listed below have been gathered for the MCG Head Office as an example:

For the 1km grid square 457 405 (SE5705), wind speeds are:

You should be aware that the information above does not take into account factors such as trees, hills, dips and other obstructions. Therefore the information above should only be used as a guideline as it may not reflect the true annual average wind speed at your site.

• An annual average wind speed of 6m/s or greater is excellent
• An annual average wind speed of 4.6m/s or greater is good
• If your site has a 4.5m/s or less wind speed it may be worth considering that a wind turbine is not a cost effective option