Australian consumers have been using more electricity during the COVID-19 pandemic, which has added to financial stress for many.

An Australian Competition and Consumer Commission study has found residential use rose significantly during the national lockdowns, which forced most people to stay at home.

In Melbourne, where restrictions have lasted longest, residential electricity use increased by between 10 and 30 per cent in April and May (depending on weather) compared to the same period last year.

ACCC chair Rod Sims said data suggested that more customers were a month behind in paying electricity bills.

He was concerned the problem may escalate as more people find themselves out of work. The unemployment rate is expected to rise from 6.8 per cent later this year.

Overall electricity use dropped by two per cent in the second quarter of 2020 due to low levels of business use.