RWE npower plc t/a Npower Renewables Oak House 1 Bridgewater Road Worcester WR4 9FP Number of complaints: 1

Date: 10 October 2007 Media: Direct mail Sector: Utilities

Ad
A newsletter, that promoted an Npower Renewables development, was entitled "Wind Power News Keeping you informed".  The text stated "The scheme will also help prevent the release of some 33,000 tonnes of carbon dioxide, the main greenhouse gas contributing to climate change, as every unit of electricity produced using wind power will displace one that would otherwise be generated using fossil fuels."  The text was linked to a foot note, which stated "National Grid Transcos Seven Year Statement 2004 supported the theory that wind power currently displaced high-emitting coal and indicated that an appropriate CO2 emissions factor for electricity generated by wind should be higher than that of the average UK mix of generating fuels in the region of 860g CO2/kWh.  Over the life of the project emission savings may change due to variations in the generating plant mix.

Issue
The Two Moors Campaign challenged Npower Renewables to substantiate the claim that the scheme would prevent the release of some 33,000 tonnes of CO2.  They believed the data upon which Npower Renewables based the figure was out of date because lower emitting gas, rather than coal, was the fuel currently being replaced by wind energy.

The CAP Code:

3.1;7.1;49.3

Response
Npower Renewables (Npower) said they submitted a planning application for a wind farm with a capacity of between 13.5 and 22.5 MW.  They said it was likely that the proposed wind farm would have a specific capacity of 18 MW and they had based the claim about CO2 on that figure.  They said the calculation used a carbon emissions factor of 860 g CO2/kWh, which, they pointed out, was recommended by the British Wind Energy Association (BWEA).  They sent a document by the BWEA entitled, Blowing Away the Myths, which stated, "In practice, the BWEA figure is robust, and founded on what is actually happening in the real world.  It is about 10% lower than the figure quoted by the Parliamentary Office of Science and Technology, and is therefore conservative ... [The] emission savings from wind energy would be around 860g/kWh, a figure that was quite different from the emissions associated with the forecast generating mix.

Npower pointed out that the ad referenced the Seven Year Statement (SYS) issued by the National Grid in 2004, but acknowledged that there had been two subsequent reports.  They said the subsequent statements both included an installed capacity utilization ranking order.  They said the ranking order was intended to inform the energy industry as to which plants allowed the greatest flexibility.  They pointed out, for instance, that nuclear, wind, hydro and gas power were less flexible than high-emitting coal and oil.  Npower maintained that both the 2005 and 2006 SYS showed that wind power was again higher up the utilisation ranking order and, therefore, more flexible than high-emitting coal and oil.  Consequently, they believed there had been no change in how wind power offset carbon dioxide by displacing coal and oil fired electricity generation.

Assessment
Upheld
The ASA noted the claim related to the yearly reduction in CO2 emissions caused by the displacement of coal-fired generation by wind power.  We noted the carbon savings claim was based on the electricity generation mix outlined in the National Grid SYS 2004 and the BWEA's recommended carbon emissions factor of 860 g CO2/kWh.  We noted the figure was representative of the emissions of a coal fired power station.  We also noted a previous ASA adjudication in 2005 had examined the issue of emissions factors and concluded, on the available evidence, that 860 g CO2/kWh was an appropriate emissions factor for wind power.  However, we also noted the complainant's assertion that the situation had now changed.  We therefore consulted the National Grid, which produced the SYS, for their view.

The National Grid said the marginal plant (i.e. the fuel likely to be displaced by wind power coming online) depended on the relative prices of coal and gas.  They pointed out that, historically, there were some seasonal variations, with prices tending to favour coal-fired generation throughout the winter months and gas-fired generation throughout the summer.  The National Grid pointed out that when coal fired generation was favoured, wind power was likely to displace gas and vice versa.  They said the SYS contained a ranking order based on generation in December and January for the previous two winters and considered that, given the seasonal pattern of generation, it was perhaps an inappropriate basis for identifying the marginal plant over a full year and, although they said the estimate of 33,000 tonnes was realistic assuming wind power displaced coal for a full year, the National Grid considered that the assumption that coal would be the marginal plant consistently over the course of a year was inappropriate.  They also considered, however, that for the same reasons, the complainant's point that gas was now consistently the marginal plant (with a typical emission factor of around 400 g CO2/kWh) was also inappropriate.  They concluded that a more accurate emissions factor for wind power lay between the two figures taking account of the variations throughout the year.

We noted previous ASA adjudications had accepted that the figure of 860 g/kWh as an appropriate carbon emissions factor for wind power.  We noted, however, that the recent fluctuations in wholesale energy prices, in particular, the large increases in the price of gas, had affected the market for electricity supply.  We understood from the National Grid, however, that the SYS was not the most appropriate source on which to base carbon offsetting claims.  Although we did not accept the complainant's assertion that gas fired generation had replaced coal fired generation as the marginal plant, we did consider that the electricity generating mix was, over a year, highly complicated and was not accurately reflected by the either the coal or gas carbon displacement figures.

We noted that Npower had followed previously accepted advice and used the 860 g CO2/kWh figure. Although we welcomed their efforts to ensure that their claim was based on an established figure, we nonetheless considered that that figure was no longer representative of the UK electricity generating mix. We therefore concluded that the carbon offset claim was inaccurate and likely to mislead.

The ad breached CAP Code clauses 3.1 (Substantiation), 7.1 (Truthfulness) and 49.3 (Environmental claims).

Action
We told Npower to ensure that future carbon savings claims were based on a more representative and rigorous carbon emissions factor.

Adjudication of the ASA Council (Non-broadcast)