The Energy Saving Trust (EST) has this week published a revised estimate for how much money a typical household can save by installing solar panels. By assuming that most UK homeowners are out of the house during the day the EST claims that solar systems will now save just £70 a year.

Previously, the EST claimed that as much as £120 could be saved on electricity bills by making use of solar energy. However, following a recent review of the technology, the EST now claims that a typical solar panel installation will save just £70 per annum.

In its original estimate, the EST worked out that around 50% of the electricity generated by domestic solar panels would be used in the home. Yet the environmental group now believes this figure to be closer to a 25% since the panels only work during the day.

Jenny Driscoll, of consumer watchdog Which? said, “Consumers must really be on their guard when it comes to solar panels. There is a massive amount of exaggeration about the benefits from salesmen. Remember the households that will benefit the most from solar photovoltaic panels are those with sunny, south-facing gardens who are in all day”.

However, while the EST’s latest findings may be applicable in some cases, industry has responded by pointing out that an increasing amount of people are working from home, some work nights and others are simply retired. The EST also seems to have forgotten about weekends.

Responding to this accusation, Virginia Graham, Chief Executive of the REAL Assurance Scheme said, “We have always been clear that the people who will benefit most from panels are those who are in during the day. We are also working with charities to ensure that vulnerable consumers are protected from mis-selling. We would like to see doorstep mis-selling banned because it is an unsuitable way to promote this technology”.

With the introduction of Smart Meters in the coming months users are also likely to change the way they use their energy, as they will be able to keep track of how much they are using and when. These observations may mean the EST will have to change its estimate once more.