Surging energy and water bills are pushing even middle-class families into hardship.
Welfare agencies report a rise in working households choosing between heating and eating – and seeking handouts or financial advice to weather soaring prices.
The warning comes amid calls for one million Victorian homes to get free upgrades over five years to make them energy efficient.
The One Million Homes Alliance fears deaths from extreme cold and heat will climb without action.
It says half the state is living in outdated homes that are expensive to heat and cool because of poor energy efficiency.
Pensioners, the unemployed, chronically ill and others in hardship would be encouraged to get "green makeovers" such as weather sealing, insulation and hot-water upgrades under the bold $2.5 billion plan.
Environment Victoria chief Kelly O'Shanassy this would reduce energy and water bills by an average $296 a year, create jobs, and deliver greenhouse savings.