The rise of rooftop solar has helped drive down electricity costs for many Australians but the head of the energy market operator warns those still on the grid have been punished with higher prices.

"I am truly concerned over the issue of an economic bypass," Audrey Zibelman, the head of the Australian Energy Market Operator, said at a Centre for Independent Studies event this week.

"We do not want to invite an economic bypass," she said, "creating the haves and the have-nots."

As electricity networks – the poles and wires – still require a fixed, per customer contribution to recover their capital, each electricity user is meant to pay an equal share. However, when people defect from the grid by installing rooftop solar it increases the proportional costs for those who still rely solely on grid power for their electricity.

Mz Zibelman raised concerns over the number of Australians defecting from the grid. While she supports the rising levels of solar rooftop installations and the increase in renewable energy, she said it was important Australians remained connected to the grid so that excess energy could be utilised and the power network better managed as the energy sector undergoes a massive transition from its old one-way power system to a multi-directional energy network.