TORONTO - Ontario is promising a $100 million rebate program to help homeowners upgrade their natural gas furnaces, water heaters and insulation, but there are no details on a start date, eligibility rules or amounts.

The goal is to reduce greenhouse gas emissions, and at the same time help create jobs and lower homeowners' natural gas bills.

Environment and Climate Change Minister Glen Murray says 37,000 customers of Enbridge Gas and Union Gas will be able to have home energy audits to identify energy-saving options.

Once the audit is done, the homeowners will be able to get some financial help -- how much is still unknown -- to buy a new furnace, water heater or insulation.

About 62 per cent of Ontario homes use natural gas for heating, compared with about 28 per cent for electricity and just three per cent for oil.

Murray says every dollar spent on energy efficiency retrofits can save natural gas customers $1.50 to $4.