ASA Adjudication on Community Windpower Ltd

Ad

A leaflet, for a wind farm development, featured several sections of information on the project. In a section, entitled "Project Highlights", the leaflet stated "Electricity generated will power approximately 28,000 homes, and by supplying the local distribution network will provide much needed electrical generation in the South West … Turbine locations have been designed to stand on abandoned taxi-ways and runways within the woodland."

Issue

The complainant challenged whether the:

1. claim that the wind farm would generate electricity for up to 28,000 homes was misleading and whether it could be substantiated; and

2. ad was misleading because it stated that the turbines would be within woodland when that was not the case.

CAP Code (Edition 11)

Response

1. Community Windpower Ltd said they calculated the electricity generation figure using industry acknowledged figures. They used the proposed Windfarm's installed capacity of up to 50 MW to determine that the maximum possible generation of electricity per year was 438,000 MWh (24hrs x 365 days x 50MW), which, using a capacity factor of 0.30, resulted in a  generation figure of 131,400 MWh/year (438,000 MWh/year x 0.30).  Community Windpower said they then used an average household electrical usage figure of 4700 kWh per home per year to arrive at the figure quoted in the ad "approximately 28,000 homes" (131,400 MWh/4700 kWh = 27957). Community Windpower pointed out that recent government studies had shown that statistically, over the last nine years, using all UK wind turbines, the average capacity factor was 0.284.  They said the studies covered all turbines, including the first generation and less efficient turbines and the industry was happy to use the 0.30 figure.

Community Windpower maintained that the capacity factor was conservative and pointed to data from the Department of Business Enterprise and Regulatory Reforms NOABL wind speed database.  They pointed out that wind speeds in the area of the proposed site were 8-8.5 m/s, which, when translated into a capacity factor, equated to a much higher figure than the generic 0.30 figure. Community Windpower said they chose the generic figure because it represented a more prudent, conservative and fair approach.

2. Community Windpower said the map printed in the leaflet showed the proposed locations of the turbines and denoted them by numbered red crossed circles. They said it was obvious from the map that turbines 1 to 6, 9 to 11 and 13 were located within the woodland.  The proposed locations of turbines 2, 3, 5, 6, 10 and 11 were on the abandoned taxi-ways and runways within the woodland. They therefore maintained that the claim was accurate.

Assessment

1. Not upheld

The ASA noted a wind farm's electricity output was dependant on wind conditions at the site.  We understood that conditions were commonly represented by a 'capacity factor', which referred to the amount of energy extracted as a fraction of the theoretical maximum amount of energy available to a source of generation.  We noted Community Windpower had used a generic capacity factor to calculate the expected electricity generation of the wind farm development.  We considered that the use of such figures might give a misleading impression if not supported by more site specific data.  We noted, however, Community Windpower had found that wind speeds at the site, taken from the NOABL wind speed data base, actually resulted in a much higher capacity factor than the one used in the ad.

We understood data from the NOABL wind speed database provided annual estimated mean wind speeds for each Ordinance Survey 1 km grid square in the UK.  We noted the data was based on extensive modelling of wind patterns and was developed by the Department of Trade and Industry.  We considered that NOABL data provided a robust estimate of the wind conditions expected in a particular area, although we considered that it did not provide the level of certainty and accuracy associated with measurements taken on-site.  We noted the claim was qualified with "approximately" and that the generic capacity factor used to calculate the claim in the ad significantly understated the capacity factor calculated from the NOABL data.  Although we acknowledged that the claim was not based on site specific data, we considered that readers were likely to understand the claim as a projection of the electricity output of the wind farm after its construction and would infer from the ad that development had not commenced.  Because the generic capacity factor significantly understated the number of houses that wind farm was expected to power, we concluded that the claim was unlikely to mislead.

On this point, we investigated the ad under CAP Code clauses 3.1 (Substantiation) and 7.1 (Truthfulness) but did not find it in breach.

2. Not upheld

We noted the wind farm comprised 20 turbines spread over an area that encompassed Davidstow Woods within which was a section of the disused Davidstow airfield and some land.  Although many of the turbines were sited in the wooded area or on the airfield, we noted a significant number were on land adjacent to the wood.  We considered that the claim in isolation was ambiguous as to the locations of the turbines.  We noted, however, the detailed site plan of the development made clear the exact location of each of the turbines and therefore considered that, when read as a whole, the leaflet was unlikely to mislead.

On this point, we investigated the ad under CAP Code clause 7.1 (Truthfulness) but did not find it in breach.

Action

No further action required.

Adjudication of the ASA Council (Non-broadcast)