According to figures from each supplier’s website – compiled by Ecotricity – between October 2013 and March 2014 the number of complaints across the energy industry increased by 23 per cent.
Of the smaller and independent suppliers, only the Co-operative Energy and First Utility saw the number of customer complaints fall (21 per cent and 15 per cent respectively) over the last six months.
Ecotricity saw their complaint levels increase by 9 per cent, while Ovo (51 per cent), Good Energy (466 per cent), Spark Energy (20 per cent) and Utility Warehouse (52 per cent) all saw increases.
Most of the big six also saw the number of complaints they received increase, apart from EDF Energy, which saw a 12 per cent fall.
Ecotricity founder Dale Vince said this spike in the number of complaints at some of the smaller suppliers is because they are struggling to cope with the “unprecedented growth”.
Ecotricity has seen the number of customers it supplied between October 2013 and March this year grow by 40 per cent (from 71,000 to 100,000), and has recruited 100 new members of staff to try and cope with the increased demand on its call centre.
Vince added: “This rate of growth can be expected to bring with it some problems in maintaining customer service levels and this looks to be occurring elsewhere within the industry.
“These figures also show that complaints to the big six continue to grow despite their relative poor performance on customer service because they have systemic problems with how they treat customers, while any issues with smaller suppliers should hopefully be a temporary problem.”