In a late written submission to the Energy and Climate Change Committee, Haven Power called for a simpler charging methodology. The committee is due to grill network bosses on 1 July.
Haven, the retail arm of Drax Group with a turnover of more than £500 million, said uncertainty over network charges acts as a barrier to entry into the market.
The submission said: “For too long insufficient consideration has been given to the impact on the competitive supply market of the current approach to recovering network revenue.”
Charges levied on industrial and commercial customers can change by tens of percentage points at short notice, with “real implications for their business”. As a supplier, Haven said it is difficult to forecast the changes or explain them to customers.
While accepting that distribution and transmission networks need to change their charges annually, Haven argued that the methodologies used are “overly complex”, particularly in distribution.
The company blamed a “dogmatic desire” on Ofgem’s part to make sure the charges reflect the costs for all network users.
British Gas has also weighed into the debate on network charges, suggesting ways Ofgem could slash £500 million a year from distribution network operators’ (DNOs) revenues.
These interventions pile pressure on DNOs ahead of Ofgem issuing draft price controls next month for the next eight-year investment round.