A new price cap on energy bills aimed at protecting vulnerable consumers is being considered by the regulator.
Ofgem said that a "safeguard tariff", which would protect more low-income households from overpaying for their energy, is one of a number of options it is looking into.
It said research carried out with the Competition and Markets Authority points to "vulnerable consumers in particular getting a poor deal".
A temporary cap, which saves over four million customers around £80 a year, was introduced in March.
Dermot Nolan, chief executive of Ofgem, said: "Protecting vulnerable consumers is a priority for Ofgem.
"We are committed to ensuring that the more disadvantaged in society are not left behind as we move towards a smarter, more competitive energy market.
"That's why we are starting new work to protect vulnerable customers, including the option of introducing a safeguard tariff for them."
Among its other proposals are plans to make switching easier and to cap warrant charges to install pre-payment meters and ban these charges altogether for the most vulnerable.
The regulator also said it wants to "take the hassle out of switching".
"We are pressing ahead with a raft of reforms to make it even easier for people to switch no matter how they choose to shop around," Mr Nolan added.