Your Home’s Second Biggest Energy User
On average, water heating accounts for about 20% of the total energy consumed in a home and is the second largest energy user after space heating. Luckily, it’s one of the most straightforward elements to upgrade and provides a good opportunity for energy savings.
Storage or Tankless?
Natural Gas Storage Water Heaters
Natural gas storage water heaters have cylindrical tanks with a ready supply of hot water. Since water is constantly heated in the tank, energy can be wasted when it isn’t in use.
Choosing an appropriately sized tank minimizes this standby heat loss. For example, a family of four with two bathrooms, a dishwasher and a clothes washer requires a 180-litre (40 gallon) tank.
Tankless Water Heaters
Tankless water heaters, also known as on-demand or instantaneous water heaters, provide hot water only as needed, eliminating the standby heating losses associated with storage tank systems. On-demand water heaters can be between 19-53% more energy-efficient than conventional systems.
The greatest potential improvements are in homes that use the least hot water, such as small dwellings and places with very efficient fixtures.
Though the initial cost is higher, wall-mounted tankless water heaters take up less space, typically last longer and have lower energy costs. To determine if this is appropriate for your home, work with an experienced mechanical professional to calculate the payback.
These systems can capture up to 60% of the waste heat that passes through drains. The heat that’s recovered is returned to the system which lessens the amount of energy required to heat additional hot water.