IMPORTANT NEW DATA (Sept 2015):
Scientific Alliance: UK Wind Turbine Output 2013 - 2014 (April 2015)
 An analysis has been undertaken of data from the UK Grid of actual wind turbine
output covering 2013 and 2014 (pdfs attached)
 The Scientific Alliance research is building up year-on-year (there is now 4 years of
data available) and contains an impartial, data-based record of the actual output
from wind turbines in the context of their contribution to national energy
requirements.
 It is different to the predicted/hypothetical outputs put forward by developers in
applications because it takes account of all the variables (efficiency, weather,
demand, availability) showing the recorded performance of operational turbines.
The data provided by an analysis of operational turbines demonstrates the gap between:
 what a turbine could produce according to the manufacturer’s specifications (which
assumes a constant steady wind at optimal speeds); this is the machine’s ‘capacity’
ie 100%.
 and what it actually produces when all the operational variables have impacted on
the turbine’s performance; this can be anything between 1.8% & approx. 49% varying hour by hour on a largely unpredictable basis.
 Nationally, the average actual output across a 12 month period is somewhere
around 29%.
 In this way, a developer who states that his/her turbine has the ‘capacity’ to fuel
1,000 homes would, in the real world, fuel an average of approx. 290 homes
intermittently; at any one time there could be a low of 18 homes and a high of 490
homes.
 In other words, no fossil-fuelled power station will close as a result of wind energy
production because the required capacity always needs to be available on stand-by
(to cover for the intermittency of wind energy supplies & to stop the lights going
out); instead we require the same capacity of fossil-fuelled power stations which
are operating inefficiently because of the on/off requirement to make way for
wind energy if and when it is available.
 “There is no correlation between UK wind turbine output and total UK electricity
demand, with output often falling as demand rises and vice-versa.” In other words,
the weather may be too windy or too still for turbines to be operational but the
conditions experienced by electricity users may be cold and dark which means that
they want more electricity at times when less is available from wind turbine sources.
Conversely, when it is warm and sunny with a pleasant breeze there is less demand
for the electricity produced …
 (NB. Wind energy can’t be stored for future use or to level out intermittency; if it is
produced but not needed, it is lost: there is, therefore, a difference between wind
energy produced and wind energy used …)
“The conclusions to be drawn from the analysis are that the increase in nominal capacity:
 Does not increase the average wind turbine capacity factor.
 Does not reduce the periods of low (less than 10% of installed capacity) or very low
(less than 5%) output.
 Does not reduce intermittency as measured by average monthly minimum output

Does not reduce intermittency or variability as measured by maximum rise and fall in
output over one hour period
 Does not indicate any possibility of closing any conventional, fossil-fuel power
stations as there is no correlation between variations in output from wind turbines
and demand on the Grid.
“Therefore, based on the above, there is no case for a continued increase in the number of
wind turbines connected to the Grid, or for the associated subsidies for wind energy, since
this is an ineffective route to lower carbon dioxide emissions.”
The paper has been published by Derek Partington from the Scientific Alliance:
http://www.scientific-alliance.org/node/945
To see UK electricity demand and the contribution from wind, see
www.gridwatch.templar.co.uk
For example, see sample printpage for 19th September 2015 at 14.05BST:
 UK demand for electricity shown at; 28.43 GW
 Wind energy supplying 0.36 GW; ie. 1.27% of this demand
 Industry figures show that wind energy capacity currently accounts for approx. 7% of
the UK’s energy needs (from 5,000 turbines) and 10% by 2020.
(RenUK (the trade organisation for the renewables industry) Onshore Wind;
http://www.renewableuk.com/en/renewable-energy/wind-energy/onshorewind/index.cfm ; printpage 190915 attached)
 So today (19/9/15), there is a clear discrepancy between capacity (7%) and actual supply
used (1.27%) which is accounted for by ‘intermittency’ and problems with accommodating
wind energy into the National Grid.
Industry stats can be found at: http://www.renewableuk.com/
RenUK onshore wind printpage 190915, attached.