Water heating is an essential aspect of any home.The many options for heating water in a home are outlined below – and for more detailed information, the Smarter Homes website provides a thorough explanation of these systems.
Solar
Solar hot water systems are simpler than solar electricity systems – water is passed through a panel which collects heat from the sun, and this water is then pumped to the hot water cylinder. These systems can be simple and economical and can be installed on any Fraemohs house design. There are different types of solar hot water systems; more detailed information is available from EECA.
Electric
Electric hot water cylinders are a common way to ensure hot water is available when needed. They work much like a household kettle, with a heating element in the cylinder. A modern, well-insulated electric hot water cylinder can minimise energy usage and is an environmentally sound choice. A well-known manufacturer in NZ is Rheem.
Heat Pump
Heat pumps can be used to heat water, and just like space heating heat pumps, they are very efficient at converting outside heat into usable heat. This type of system is more efficient than a traditional electric hot water cylinder. Rheem and Ecoenergy offer such systems.
Gas
As mentioned in the ‘Energy Sources’ section, natural gas and LPG are clean-burning but non-renewable fuels. Gas can be used to heat hot water cylinders, or be used in a ‘continuous flow’ system. This latter type of system only heats water when necessary, so does not waste energy keeping a cylinder hot when water is not being used. Rheem, Rinnai and Bosch make gas hot water systems.
‘Wetback’ Systems and Boilers
Wetback systems help heat the hot water cylinder by running water across a woodburner or similar heating system. This could save electricity costs. Also, modern heating systems (which can be fuelled by wood, gas, diesel or coal) can heat water as well as living space from a central boiler. As an example, Ecomax boilers offer the combination of central heating and hot water heating using wood pellets.