Camilty Wind Farm - Partnerships for Renewables

Camilty Wind Farm
carbon savings from wind farms on Scottish peat lands – A new approach (Nayak et al.
2011).
6.4 Expected Energy Yield and Associated Avoidance of Carbon Dioxide
Emissions
Renewable Electricity Generation
6.4.1 Taking into account the candidate turbine for the site, it is expected that six turbines with a
total installed capacity of 20.4 MW could generate up to 46.46 gigawatt-hours (GWh) of
renewable electricity per year based on a capacity factor of 26 % informed by site studies. In
Scotland, the most recent information available shows that the average capacity factor
measured between 1998 and 2004 was 30% (DTI, 2006, Energy Trends, March 2006).
These figures are derived as follows (using a 26 % capacity factor):
20,400kilowatts kW (6 × 3.4 MW turbine) × 8,760 hours/year × 0.26 (capacity factor) =
46,463,040 kilowatt hours (kWh) or 46.46GWh
6.4.2 The DECC Excel Spreadsheet of Sub-National Local Authority Electricity Consumption
Statistics 2005 to 2011 (DECC, 2012) gives 2011 UK domestic electricity consumption (sales
per household) as 4,266 kWh per household. This is a higher consumption figure than that
used by Renewables UK who advocate 3,300 kWh based on data from Ofgem (Ofgem,
2011). Based on the more conservative 4,266 kWh household figure and the predicted
electricity generation of up to 46.46 GWh it is estimated that the yearly output from the wind
turbines will be equivalent to the approximate domestic electricity needs of up to 10,891
average households in Britain (46,463,040 ÷ 4,266 = 10,891). It should be noted that using
the average domestic electricity consumption figure for households in West Lothian of 4,143
kWh (DECC 2012), the development is expected to generate sufficient electricity for 11,215
homes (46,463,040 ÷ 4,143 = 11,215).
6.4.3 In 2011, there were approximately 73,439 households in the West Lothian Council area
(National Records of Scotland, 2011); therefore the proposed wind farm alone could supply
approximately 14.8 % of the annual electricity demand for West Lothian. This percentage
may decrease slightly during the lifetime of the wind farm due to predicted population growth
in Scotland as a whole. However, there is also the strong possibility that domestic electricity
consumption may reduce due to energy efficiency measures proposed by the Scottish
Government (2011b). Although these figures are open to variation, in principle they show
that the proposed wind farm will provide a proportion of electricity used in the local area.
Reductions in Atmospheric Emissions of CO 2
6.4.4 It is widely accepted that electricity produced from wind energy has a positive effect with
regard to reducing CO 2 emissions. In estimating the actual saving, it is important to consider
the mix of alternative sources of electricity generation, for example coal powered and gas
powered, and there has been much debate about the amount of CO 2 emissions that could
potentially be saved as a result of switching to wind generation.
6.4.5 In September 2008, the Advertising Standards Authority endorsed a figure of 430 gCO 2 /kWh,
based on the assumption that the energy generated by the wind turbines displaces Combined
Cycle Gas Turbines and an average mix generation (430 gCO 2 /kWh). This number is
endorsed by Renewables UK (2012).
March 2013 6-5 ES Chapter 6
Climate Change and Atmospheric Emissions
Copyright Partnerships for Renewables Development Co. Ltd 2013 ©