Ontario homeowners will be paying up to 15 per cent more for their electricity starting May 1, but there may be relief for those on low incomes.

The Ontario Energy Board announced the rate hike Wednesday afternoon. It said that, while a hot summer in 2005 increased demand, consumers paid less for electricity than it cost to supply it.

Hydro rates will climb on May 1 to up to 6.7 cents per kilowatt hour.

On the heels of the increase announcement, the provincial government proposed legislation to give low-income families a one-time rebate.

Finance Minister Dwight Duncan wants a $120 payment to go to families with a net income of $23,000 or less to counteract the electricity rate increase.

If the bill passes, up to 1.5 million Ontario families would be eligible for the rebates.

Duncan proposed the break just after Energy Minister Donna Cansfield insisted the province would no longer subsidize consumers.

She says they haven't been paying the true cost of electricity, and urged homeowners to cut back on their energy use to save money.

The energy board set a new price of 5.8 cents per kilowatt-hour for the first 600 kilowatts of electricity used, up from the current price of five cents.

For anything above 600 kilowatt hours, homeowners will pay 6.7 cents, up from 5.8 cents.

The board estimates most consumers will see their bills jump between three to 15 per cent.

Rate changes don't affect those homeowners who have signed with an electricity retailer that's locked in at a fixed amount.