And, Ausgrid is urging customers to make sure their homes are ready for winter. 

Energy efficiency expert Dr Robert Simpson said winter electricity bills were generally the highest of the year.

But, there are some simple things people can do to lessen the impact on the household budget. 

“A good first step is to walk around your home to work out how you can keep heat inside,” Dr Simpson said.

“If you are losing heat through doors and windows it means you need to run heaters for longer, which costs you more. 

“Consider using door snakes, draught stoppers, foam window sealing tape and closing blinds and curtains to reduce heat loss and stop any draughts. 

”It’s also worth investing in rugs for tile or wooden floors to keep your home cosy for winter and making sure your home is properly insulated can provide big savings.”

If you are buying a new heater or heating system it’s important to choose the right one for your situation. 

“Reverse-cycle air-conditioners and gas heating systems are good options for larger spaces,” Dr Simpson said.

“They are more expensive upfront but if used efficiently they cost up to two thirds less to run than plug-in heaters.”

Portable plug-in heaters are better suited for using in small spaces for short periods of time. 

"Plug-in heaters can be cheap to buy but can be costly to run and it is easy to spend more money on electricity from using a personal fan heater in one week, than the cost of the heater itself,” he said. 

Ausgrid research shows more than 80 per cent of households heat their homes to 22 degrees or above. 

“A comfortable room temperature in winter is considered to be between 18 and 21 degrees,” Dr Simpson said.

“Every degree of heating above that can add 10 per cent to the running costs.”

If you use plug-in heaters, give them a safety check when you pull them out for winter and look for frayed cords. 

Heaters also use a lot of power so don’t piggy back adaptors and keep them a safe distance from combustible items.