Electricity and Gas Complaints Commissioner Judi Jones says complaints to her office about high bills have doubled this winter compared with last year.
Ms Jones says the commission received 76 complaints between April to August this year, compared with 37 complaints for the same period in 2008.
The Federation of Family Budgeting Services says people seeking help are often two months behind on payments for power.
Work and Income says it has paid out 36,607 benefit advances so customers can cover power and energy bills in the year to June. That is 6529 more than the previous year.
Ms Jones says some monthly bills this winter have been a shock for customers, reaching as much as $800 for a family.
