Storage water heaters
Installing a water heater jacket on a tank can save money each year. Making sure to drain your tank on a regular basis will help it run longer and more efficiently for an extra few years.
When considering a water heater model for your home, estimate its energy efficiency and annual operating cost. Then, compare costs with other more and/or less energy-efficient models. This will help you determine the energy savings and payback period of investing in a more energy-efficient model, which will probably have a higher purchase price.
The energy factor (EF) indicates a water heater's overall energy efficiency based on the amount of hot water produced per unit of fuel consumed over a typical day. This includes the following:
- Recovery Efficiency – how efficiently the heat from the energy source is transferred to the water
- Standby losses – the percentage of heat loss per hour from the stored water compared to the heat content of the water (water heaters with storage tanks)
- Cycling Losses – the loss of heat as the water circulates through a water heater tank, and/or inlet and outlet pipes.
The higher the energy factor, the more efficient the water heater. However, higher energy factor values don't always mean lower annual operating costs, especially when you compare fuel sources.
Product literature from a manufacturer usually provides a water heater model's energy factor. Don't choose a water heater model based solely on its energy factor. When selecting a water heater, it's also important to consider size and first hour rating, fuel type, and overall cost.