The Energy Saving Trust, part funded by the government, has told consumers that a new boiler will save between £105 and £310 a year. Its figures are the gold standard in the energy industry, and have been widely used in adverts by companies such as British Gas to persuade householders to spend thousands of pounds replacing an old boiler. But the DECC figures suggest that the typical annual saving on bills has, in reality, been closer to just £70 a year.
In 2009 the Labour government launched its £200m boiler scrappage scheme which gave £400 off a new boiler. Around 125,000 homes replaced their often working boiler with a new one, encouraged by what now look like discredited figures.
The Energy Saving Trust says it is reviewing its financial guidance and will, later this month, downgrade the savings it tells consumers they can expect to earn from installing energy efficiency measures. It could come as the final blow for the Green Deal programme, which relies on estimates of future financial savings to encourage consumers to take out loans to pay for energy-saving home improvements.
The figures are contained in the National Energy Efficiency Data-Framework (NEED) published by the DECC late last year. It examined “observed” savings from loft insulation in 21,000 homes, new boilers in nearly 14,000 homes, and cavity wall insulation installed in 16,000 homes, and compared them with properties that did not have the measures installed. It found that on average, loft insulation decreases home gas consumption by 1.7%, cavity wall insulation by 7.8% and a new boiler by 9.2% (median figures were slightly higher). Installing all three produced greater savings.
It concluded that: “There are significant savings from installations of all the energy efficiency measures considered in this report, and provides further support for the value of installing each individually or in combination.”