|Number of turbines
|Rating of turbines
|Wind farm size
|Average Households supplied
The capacity factor used in these calculations is 27%.
Once a turbine is in operation, it will be monitored remotely with maintenance personnel making periodic visits. A turbine is expected to have an operational life of approximately 25 years. After this time it will be decommissioned in order to return the site to its previous state.
How the figures are calculated:
1) Predicted Output
capacity of wind farm (MW) x capacity factor*
hours per annum (8,760 hours)
predicted output (MW hours per annum)
*The calculation for the Saddle Hill Wind Farm proposal is based on a capacity factor of 27.0% is the average capacity factor of onshore wind in the UK spread over the last 13 years (2000-2013) as calculated by DECC.
‘Capacity factor’ is the % of the wind farm’s maximum output expected over a year. 100% would mean that the wind turbines were generating their maximum output all the time, a little like driving a car at maximum speed all the time. In reality, the wind is usually blowing and the wind turbines generate electricity most of the time, at a greater or lesser proportion of their maximum possible output.
MW is the abbreviation of megawatt, a unit of power equal to one million watts.
2) Households Supplied*
average UK electricity consumption per household per annum
number of households electricity needs supplied
*This calculation for the Saddle Hill Wind Farm proposal is based on a mean annual household usage in Great Britain of 4.27 MWh per year as calculated by DECC. Statistics from 2005 - 2011 (2011 data).
The 'Average Households supplied' figure is provided for comparison purposes only and is based on the capacity factor figure shown above.