The 25-year-old university student rents her home, and she suffers from narcolepsy. You wouldn't think her housing situation would affect her condition, but it does.

Because she rents, Ms Summers has little control over how her home handles the heat.

It's drafty. There's a hole in the roof. She says it's got poor insulation. It's hot in the heat and icy in the cold.

Her body can't tell on its own when it should be awake or not, so a hot, sweaty night means a lot more than just tossing and turning.

"A narcolept is already sitting on two days' sleep deprivation, so every hour you lose makes that exponentially worse," she says.

Ms Summers is in a bad situation that is common among renters. She is stuck with the house she has rented. Even if she could afford to, she can't do what's necessary to fix it.

She is also, like many tenants, on a low income. Reliant on Austudy, she feels tied to the home she is in because, as she says: "Moving is expensive".

"Tenants are basically at the whim of the landlord," Tenants Union of Victoria policy officer Yaelle Caspi​ said. "If the landlord doesn't want to invest in increasing the energy efficiency of a property then the tenant finds themselves stuck. This is particularly a problem for low-income tenants, and tenants with disabilities or the elderly."

Kildonan UnitingCare conducts audits on behalf of AGL of those participating in the energy retailer's hardship program.

In its most recent audit, for the first six months of the year, it found 47 per cent of those in hardship were tenants – either in public housing or in the private market – despite only 28 per cent of Victorians being renters.

And, as summer approaches, disconnections are on the rise. The Energy and Water Ombudsman of Victoria's latest affordability report shows disconnections of energy, gas and water were 36 per cent higher during the three months to the end of September, than they were in the previous quarter, breaking with a downward trend that had lasted more than a year.

The Victorian Residential Tenancies Act is currently being reviewed by the state government. Ms Caspi said there should be minimum standards for rental properties that address the health, safety and energy efficiency of the dwelling.

"There are currently no minimum standards in place for rental properties. Houses can be of a very low standard and still be rented out," she said. "The private rental market is so highly competitive that there is no incentive for landlords to make improvements to their properties."

A government spokesperson said the issue of minimum standards for rental properties "has been identified as an issue and it will be addressed as part of the government's review".

Environment Victoria chief executive Mark Wakeham said tenants suffered from a "split incentive" in the rental market, because the landlord controls the energy efficiency of the home, but the tenant pays the bills.

"You're buying into a house with large running costs, and they are not disclosed," he said. "Renters are probably less able to make changes to the thermal performance or the energy efficiency of their homes. A regulator response is really what's needed."