In a typical Canadian home, water heating is the second biggest energy user after space heating. In fact, water heating usually accounts for up to 20 percent of your total utility costs. The good news is that it's possible to reduce your water heating costs by selecting an energy-efficient water heater that meets your needs, installing some basic water-saving devices and adjusting your water-using habits.
Many water-heating models are available - and like any other major household appliance, the cost of purchasing and operating a water heater can vary significantly from one model to another. Don't just take the word of your plumber, contractor or utility about what product to install in your home, become an informed consumer and take control of your hot-water costs and consumption.
Source: Natural Resouces Canada (NRCan) - Office of Energy Efficiency