Smart meter data has revealed businesses electricity is being wasted by firms that are leaving lights and machinery on when they are not in use.
British Gas collected statistics from over 6,000 smart meters installed by firms and re revealed as much as half of their electricity is being used unnecessarily.
Examples included pubs leaving fruit machines running when they are closed and retailers in shopping centres keeping lights on 24 hours a day.
Director of small and medium-sized business energy at British Gas Business Marc England noted many companies "don't understand their electricity costs and how they could reduce them".
This is supported by a recent report from Siemens, which found over a quarter (27 per cent) of company board members do not know their firm's gas and electricity expenditure, despite 83 per cent believing the company is committed to managing usage.
British Gas estimates firms that switch off lights in their car park when it is not in use could save £1,200 on their bill every year.
You could save up to £1,300 a year on your commercial energy bills - visit energyhelpline.com or call us on 0800 970 26 26