Today there is a wide range of systems available to heat water for use in the house. Making the right choice may mean larger energy savings as well as never running out of hot water.
THE SYSTEM AVAILABLE
ELECTRICITY
• Mains pressure electric hot water heaters in storage tanks.
The water is stored in a large tank either inside or outside the house. The water is heated when needed or during off-peak periods. These tanks normally last for about 12 years before they have to be renewed. New tank designs with two elements, one top and bottom, mean you can heat a small amount of water quickly.
• Low pressure gravity tanks.
These are place in the roof space and are good where off-peak electricity is available. Reduced flow at taps can occur where 12mm diameter pipes are used. Copper tanks need replacing less often except in areas with corrosive water.
• Instantaneous electric systems.
Good in small households with small usage of hot water, they may not heat the water enough in cold climates.
NATURAL GAS
• Storage tank.
May require a pilot light that burns 24 hours a day and thus uses a significant amount of gas. This could account for a large amount of your bill if you use only a little hot water. It can produce hot water very quickly at any time.
• Instantaneous systems.
Should seriously be considered as these give you all the hot water you need antime and at preset temperatures. You pay only for what you use. These wall mounted units don’t use any floor space.
• Combined solar/backup systems.
These solar units mounted on the roof have a gas or electric back-up unit heat the water on cloudy days. The initial cost of these units has to be weighed against the advantages.
LPG
Can be economical if you ensure that you qualify for the hot water rate. This requires the storage of tanks near the house.
SOLAR SYSTEMS
Before deciding on installing such a system, do some careful research as the large capital investment may never be recouped. These can burst in cold climates.