By law, energy performance energy labels for products such as dishwashers, ovens and fridges must be displayed as prominently on a website as they are in shops.

But a study by MarketWatch, a group of civil society organisations, found that 20% of online goods had no label, 1% had the wrong label, and 35% were displayed in outdated or inaccessible forms.

These included pop-up boxes that consumers could only find by scrolling down to poorly advertised links at the bottom of the page.

Up to 10% of Europe’s expected energy savings by 2020 could be lost as a result of non-compliant products, the paper says – as much as the current residential electricity consumption of central and east Europe.

Alun Jones, a researcher for the report said: “Energy labels could save households €465 on their energy bills each year but, with increasing numbers of consumers buying and researching their products online, the widespread mislabeling and no-labelling of products could lead many to miss out on their share of savings”.

Polls suggest that three quarters of Britons now buy goods online, with more than a third of UK shoppers taking to the web to find electronic homes appliances.

Yet only a quarter of white goods sold online in the UK in last year’s MarketWatch inspections were correctly labelled. Half had no energy information at all.

While all British wine storage appliances were correctly labelled across physical and online stores, the same was only true for 18% of dishwashers, 20% of washer-driers, and 32% of TVs.

Range hood extractor fans were the worst labelled British product with 74% receiving an inaccurate description.

The energy description of goods in UK high street stores is improving but 49% of home appliances sold there last year were still wrongly labelled, if at all.

Small retailers, independent shops and kitchen stores were particularly poor performers but websites emerged as “by far the biggest area of concern,” according to Jones, who is also a spokesman for the Coolproducts campaign.

Angeliki Malizou, an energy expert for the European consumers organisation BEUC said: “This study comes as no surprise. Consumer groups have repeatedly flagged problems with labels incorrectly displayed on websites.

“Online shopping is becoming consumers’ daily bread. That’s why it is key that information on energy consumption and efficiency is easily accessible before purchase. EU states need to step up their efforts to ensure that traders play by the rules in the online world.”

The Italian MEP Dario Tamburrano told the Guardian he was “astonished” that the situation had arisen at a time when online commerce was growing by 18% a year.

“It should be easier for market surveillance authorities to check compliance in the online environment than in brick-and-mortar shops, but this is not happening,” he said. “We need to reinforce surveillance, to empower citizens with improved information and to better define [producer] roles and responsibilities.”

The results of the MarketWatch report, which surveyed more than 150,000 products retailing at 151 physical shops and 118 online vendors, will be shared with national market surveillance authorities.

Industry lobbying in Brussels helped to create the current system in which products can be awarded A+, A++ or A+++ energy labels, which have caused some confusion to shoppers. The lowest grade for a washing machine energy label at present is A+.

The EU plans to return to a straight A-G scale for energy labels in the near future.

This article first appeared on the Guardian

Edie is part of the Guardian Environment Network

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