Customers of Enbridge Gas Distribution Inc. will see the cost of heating their homes and hot water go up starting April 1 as a result of a rate increase granted Tuesday by the Ontario Energy Board.

The new rate being charged by Enbridge Gas, a wholly owned subsidiary of Enbridge Inc. (TSX:ENB), is 21.16 cents a cubic metre, less a cost adjustment of 0.046 cents, for an effective rate of 21.12 cents a cubic metre.

The previous rate for customers who buy their gas directly from Enbridge was 19.96 cents a cubic metre.

The provincial regular said the increase means the average Enbridge residential customer using 3,064 cubic metres of gas annually will pay an extra $36 a year.

"The change reflects an increase in what Enbridge forecasts it will have to pay for the natural gas it supplies its customers over the next twelve months and an increase to the gas cost adjustment for the period of April 1 to June 30, 2010," the OEB said in a news release.

Enbridge Gas Distribution does not earn a profit on the price of natural gas. Gas supply costs are passed through to customers without any markup. Any difference between forecast costs and actual prices is either collected from, or returned to, customers through a gas cost adjustment.

Meanwhile, the regulator said other changes will impact both customers who purchase gas directly from Enbridge and those who have a contract with a natural gas marketer.

These changes reflect a previous board decision approving rates and other charges to sell, distribute, transmit and store natural gas.

Consumers will also see a one-time credit of about $6 in the month of April to reflect changes to customer and delivery charges for the period Jan. 1 to March 31, 2010, and a charge of about $4 in April and May to clear deferral accounts. These changes apply to customers who purchase their natural gas directly from Enbridge.

Customers who have a contract with a natural gas marketer will also see these changes, however the amounts will differ, the OEB said.

Every three months, the board, which regulates Ontario's electricity and natural gas sectors, reviews natural gas commodity prices Enbridge charges its customers and adjusts them if necessary.