3D model of the open-design water heater and electricity system (ODWHES). The ODWHES is a domestic electricity system combined with a water heater. Two water heaters are shown in the model, one working on electricity, another working on a fuel (supplied from a fuel tank).
Both are designed so that the water quantity heated by either electric coils or the fuel burner is kept as low as possible. This is done by using a flow-through type heating installation. A tank is present to allow the use of solar heating. With the second setup (gas-fired heater) a small tank (80L) is present to allow waste heat (from the fumes) from the gas-fired burner to not be wasted. The water heated by the sun is implemented as a primary heating step, and the water heated by the sun will not yet be very warm. The flow-through heater is then used to get the temperature upto a high enough temperature for a variety of applications.
Note that an extra layer of insulation can be placed around the tank (preferably ecological/cradle to cradle); shattered glas, or gravel (both materials are heat resistant, more dense then air, absorb heat well).
An additional function that can be implemented is a timer on the water heater, to switch it off when no heated water needs to be available. This can be done by using a time switch and setting it to: * disconnect power/extinguish the pilot flame at specific times of the week (ie if the family follows a specific routine, ie regarding bathing, ...) OR by * disconnecting power when the water in the tank falls below a certain temperature; this is useful if there's really good insulation present
Note that besides using a solar thermal collector, a soil or groundwater heat pump can also be used.
The domestic electricity system is a combination of a 3-phase, 230V, 50Hz system and a DC system. This combination allows the use of both DC appliances (ie LED/LEC lights), DC energy storage systems (ie electrochemical batteries) aswell as AC appliances. Both the private AC/DC power produced and the AC power consumed from the mains electricity grid is metered. See the 'Purchasing_the_models' link at appropedia's AT_CAD_Team for additional information on the model