What water heating system to choose for your new house?
A gas-based system, or an electric system?
A solar electric PV (photovoltaic) system?
A solar thermal system, backed up by a small gas or electric system?
A heat pump water heater?
A condensing gas system?
An on-demand or a tank-style gas-fired system?
A heating boiler system?
Water heating bills amount to $300 to $450 per year in average American households. Water heating is one of our biggest energy expenses.
Electric-resistance water heaters are inexpensive, but they have high running costs. They aren't a good option for large or even for average hot water needs.
The alternatives? Gas, solar, or... electric heat pump water heaters.
See:
Hot Water and Heat Pumps
Electric Vs. Gas Water Heating Efficiency
Solar water heaters can provide energy savings up to 80% in warmer climates, where thermosyphon solar systems are very effective and relatively inexpensive.
But the prices of solar water heaters for cold climates are high. Drainback and other solar water heating systems for cold climates, with anti-freezing devices, can cost $4.000-$5.000 or more.
See: Solar Water Heaters Guide
Pay attention to high flow-rate faucets and shower heads.
Replacing an old shower head with an energy-efficient low-rate unit (less than 2.5 gallon/9 liters of hot water per minute) may save 20.000 gallons (75.000 litters) of water per year (average American homes)
See: Improvements in Water Heating
In new construction, or in major renovations, pay special attention to your hot water distribution system. Oversized pipes, long piping runs and pipes with insufficient insulation are responsible for huge energy and water losses.
See: Improvements in Water Heating Systems
Size properly your water heater.
Oversized water heaters will not provide the savings you seek, and will cost more.
See: Water Heaters Size
Dishwashers and other appliances can consume large amounts of hot water.
See:
Clothes Washers Efficiency
Clothes Dryers Efficiency
Dishwashers Efficiency
Tankless water heaters eliminates stand-by energy loss. But replacing a storage water heater with a tankless unit is rarely advantageous.
See:
Tankless vs. Storage Water Heaters
Condensing gas water heaters can provide energy savings up to 30% when compared with standard gas units.
But they are a lot more expensive than regular gas water heaters, and may not be advantageous in average homes.
See:
Condensing vs. Regular Gas Water Heaters
Water Heaters Energy Factor
You can have an electric (heat pump) or a gas (boiler, condensing water heater) system to provide both hot water and heat for your home.
But do these systems make economical sense in average homes?
See:
Integrated Water Heating with Boilers and Heat Pumps
Electric point-of-use water heaters can save water and energy by eliminating the wait for hot water.
They can be very useful in hot climates, where the average water temperature is high, and where hot water needs are low or moderate.
But what about their uses in other climates?
See:
Electric Point-of-Use Water Heaters
Water Heaters Prices
Water Heaters: Manufacturers