With the launch of the One X+, O2 and HTC tried a new approach of taking the charger out of the box and including only a USB-cable to promote environmental savings. Now both companies are back with word that the pilot programme was a success and that every four-in-five handsets were sold charger free.

For customers who absolutely needed one, a charger was available to buy separately, but 82 per cent of customers found they didn't, exceeding O2's target of 70 per cent. 

“The results of the trial demonstrate a clear willingness among consumers to consider and respond to the environmental argument for taking a phone charger-free," said Ronan Dunne, CEO of O2. "I now hope that as a result of this study the rest of the industry will now consider joining us in our campaign to take chargers out of the box for good.”

O2 explained last year that 70 per cent of customers who buy one of the 30 million new handsets sold in the UK each year already have the relevant charger which, as a result, leaves more than 100 million chargers unused.

Amazon was the first company to offer only a USB to Micro-USB cable with its Amazon Kindle, forcing users to charge the tablet via a computer or by plugging it into an existing charger that houses a USB port. 

After seeing the success of the pilot programme, Dunne says O2 aims to sell all handsets charger-free by 2015, set to save 18,700 tonnes of components.