Boiler
A boiler is a device, commonly mechanical, that heats fluid, with a water heater being the most common and is used to heat water. The heated water is commonly mixed with cold water to create various temperatures of warm water used in showers and bathroom and kitchen sinks, but also bidet toilets, and radiant heaters.
A common method used a steel tank with an electrical, natural gas, or propane powered heating element which kept the water in the tank at a specified temperature. These devices are unable to maintain the hot water temperature when there is a large demand for hot water. They also cycled the heating element on and off, regardless if hot water was needed, to maintain the temperature in the tank.
An energy efficient alternative to a hot water tank is a tankless water heater which uses a higher energy consumption to heat the water on demand, but only energy is consumed when hot water is needed. When properly sized, tankless water heaters are able to maintain the hot water temperature even when there is a large demand.
A solar water heater uses the sun's rays to heat water and can be used alone or in conjunction with tank or tankless water heaters.[1]
The standing hot water left in the pipes between the water heater and the device using the hot water will cool down when the hot water is not being used. This results in cold water initially coming out of the device when hot water is expected which can be unpleasant in showers and bidet toilets. Approximately 4,000 gallons of water per person each year is wasted as the water is purged before use to ensure hot water is available when needed.[2] Insulating the hot water lines and using a recirculating pump with a return line help to ensure hot water is available when expected.
Fuel sources
Wood chips
A wood chip boiler is a boiler fueled by wood chips. Wood chips are a renewable resource that requires little processing before use but is bulkier than wood pellets and less efficient to ship. It is more economical than wood pellets when the wood is grown and chipped near the boiler.[3]
Rocket mass water heater
A rocket mass stove can be converted into a water heater.[4]
Links
- Recirculation pump - YouTube