Ad description

A leaflet, for an electricity supplier, was headed "Heat Electric: it all adds up". Text inside the leaflet stated "Pipe free central heating The next generation of whole house electric heating is here ... Plus you have the peace of mind of knowing that your heating is low maintenance, leak free, fume free, noise free and low carbon".


Guernsey Gas Ltd challenged whether the claim that heating delivered through the advertiser's electricity supply was "low carbon" was misleading and could be substantiated.


Guernsey Electricity Ltd (GE) said the main alternatives to electric heating on Guernsey were oil and gas. The carbon intensity of electricity consumed on Guernsey in the financial year of 2010–11 was 0.178 kg CO2/kWh, which compared to carbon intensities of 0.244 kg CO2/kWh for oil and 0.214 kg CO2/kWh for gas in the same period.

Electricity on Guernsey originated from two sources: electricity generated on island at a plant which used heavy fuel oil ('on-island electricity'); and electricity imported from EDF in France ('imported electricity'), which was generated from a variety of energy sources including nuclear and renewable. On-island electricity had a higher carbon intensity than imported electricity (in 2010–11, 0.681 kg CO2/kWh compared to 0.0385 kg CO2/kWh). In 2010–11, approximately 22% of electricity used on Guernsey was generated on-island and 78% was imported.

GE said the type of heating advertised in the leaflet – storage heaters – used 'Off Peak' energy which tended to be sold at times when they had access to cheaper imported energy; that resulted in the heaters using about 85% imported electricity and 15% on-island electricity. They said that translated to a carbon intensity of 0.135 kg CO2/kWh, which was lower than that for both oil and gas. They believed the use of the term "low carbon" was therefore justifiable on that basis. They also considered the claim was justified because an ASA adjudication, published in 2010, had found that it was misleading for an ad to state that electricity on Jersey was "not a low carbon fuel". They said that whilst electricity on Guernsey had a slightly different mix of on-island and imported electricity, the carbon intensity of electricity on Guernsey was not significantly higher than on Jersey.

GE said as a result of the complaint they had researched whether there was a universally accepted standard for 'low carbon' energy claims, but had found there was none. They recognised the lack of definition could lead to confusion for consumers and it was therefore not their intention to use it in the same context again.


Not upheld

The ASA considered that GE's response, in which they compared the carbon intensities of the main sources of energy supply on Guernsey, demonstrated that they believed the claim that their electricity was "low carbon" was a comparative claim. We noted the paragraph above the "low carbon" claim linked to text which stated "Compared to gas central heating ..." and we therefore agreed that consumers would interpret the claim to be that electric heating had a lower carbon intensity than gas central heating on Guernsey.

We reviewed the information provided by GE in relation to the generation of on-island electricity, and were satisfied that they had demonstrated that the figure they had provided for the carbon intensity of on-island electricity was a reasonable one. We also reviewed the figures GE had provided in relation to imported electricity, which were based on monthly published carbon intensity figures for electricity produced by EDF in France.

We noted that in June and July 2010 we had adjudicated on advertising claims made by Guernsey Gas relating to the carbon intensity of electricity on Jersey and Guernsey, and at that time had sought advice from the Carbon Trust as to what would be a reasonable carbon intensity for electricity imported to the islands from EDF in France. We had understood that although electricity from other suppliers, including electricity imported into France, would be included in the electricity imported onto Guernsey, the proportions were small and would not have a significant effect on the carbon intensity of electricity produced in France by EDF. We asked the Carbon Trust to provide an update on the figures they had provided for us in 2010. They concluded that a reasonable figure for the carbon intensity of electricity produced by EDF in France was 0.0304 kg CO2/kWh, and also provided a figure which included imports to EDF in France, which was marginally higher. We considered that, because that figure was only marginally higher, it demonstrated that the inclusion of imports to EDF France did not have a significant effect on the overall carbon intensity of electricity on Guernsey and it was therefore reasonable to use the figure for electricity produced by EDF only. We noted the figure used by GE was higher than that calculated by the Carbon Trust, but only marginally so. We were therefore satisfied that GE had used a reasonable figure for the carbon intensity of electricity imported to Guernsey. Furthermore, we noted that using both the GE figure and the Carbon Trust's figure resulted in an overall carbon intensity for electricity supplied on Guernsey in 2010–11 which was lower than that of gas (based on the mix of 22% on-island and 78% imported electricity).

We noted GE believed the "low carbon" claim in the ad related specifically to storage heaters, which used Off Peak electricity and therefore had a lower carbon intensity than the overall 2010–11 figure because it was comprised of a higher proportion of imported electricity. However, we did not agree that it was clear that the "low carbon" claim related specifically to storage heaters, because the leaflet advertised a range of heating options. In particular, the paragraph which preceded the "low carbon" claim referred to a typical system for a two-bedroom house, which was illustrated in cartoon form on the first page of the leaflet; that illustration included heaters which were not storage heaters. We therefore concluded it was not appropriate to use a carbon intensity figure based solely on Off Peak electricity to support the "low carbon" claim in the context of this ad, and instead the appropriate figure was the overall carbon intensity of electricity supplied on Guernsey in 2010–11. However, we noted that figure was below the figures for both gas and oil.

Because the overall carbon intensity of electricity supplied on Guernsey was less than that for gas, we concluded the claim "low carbon", in the context of an ad which compared electric heating to gas central heating, was not materially misleading.

We investigated the ad under CAP Code rules  3.1 3.1 Marketing communications must not materially mislead or be likely to do so.  (Misleading advertising),  3.7 3.7 Before distributing or submitting a marketing communication for publication, marketers must hold documentary evidence to prove claims that consumers are likely to regard as objective and that are capable of objective substantiation. The ASA may regard claims as misleading in the absence of adequate substantiation.  (Substantiation),  3.33 3.33 Marketing communications that include a comparison with an identifiable competitor must not mislead, or be likely to mislead, the consumer about either the advertised product or the competing product.  (Comparisons with Identifiable Competitors), 11.1 and  11.3 11.3 Absolute claims must be supported by a high level of substantiation. Comparative claims such as "greener" or "friendlier" can be justified, for example, if the advertised product provides a total environmental benefit over that of the marketer's previous product or competitor products and the basis of the comparison is clear.  (Environmental claims), but did not find it in breach.


No further action necessary.

CAP Code (Edition 12)

11.3     3.1     3.33     3.7    

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