Water heater with intermittent energy source

Abstract

A water heater with a hot water compartment, the volume of which is decreased when hot water is discharged. The remaining hot water is prevented from mixing with replacement cold water. The volume of the compartment is increased again when cold water has been heated and is pushed into the hot water compartment. The water heater is divided into a receiving compartment for water at ambient temperature and a compartment from which heated water is discharged for normal usage. The previously heated water is thereby prevented from mixing with replacement cold water. All compartments can be heated or the compartments can be heated individually. The water heater keeps the hot water temperature high between usage activities, and is suited for an intermittent energy source, e.g. solar power.

1 . A water heater with multiple fixed volume compartments separated from one another by respective separation walls and allowing water to flow from a top of one compartment to another compartment when water flows out of the water heater in normal operation, characterized by a heat source that functions according to at least one of the implementations in the following group:
 a) a structure to heat the water in a selected number of compartments only and not heat the water in all the compartments;   b) a structure to use a preferred heat source and an auxiliary heat source, wherein the auxiliary heat source is only used when the preferred heat source does not provide enough heat to comply with hot water demand from the water heater; and   c) a structure to use a preferred heat source and an auxiliary heat source in a way to minimize the use of the auxiliary heat source but still provide good availability of hot water from the water heater to satisfy user demand, with the preferred heat source of an intermittent nature.   
     
     
         2 . The water heater of  claim 1  wherein a control unit monitors the temperature in the water heater at least at one location and controls the heating of one or more compartments of water in a way to provide sufficient hot water for normal average usage but in an energy efficient manner by not heating more water than what would typically be needed in a time period to follow. 
     
     
         3 . The water heater of  claim 2  wherein a decision for heating multiple compartments is taken with specific consideration of the time of day or day of the week. 
     
     
         4 . The water heater of  claim 1  wherein a control unit monitors the temperature in the water heater at least at one location and controls the heating of one or more compartments of water in a way to provide sufficient hot water for normal average usage but in an energy efficient manner by not heating more water than what would typically be needed in a time period to follow. 
     
     
         5 . The water heater of  claim 1  where the preferred heat source is solar and the auxiliary heat source is electricity or LPG and wherein a control unit monitors the water temperature in the water heater at least at one location and controls the auxiliary source heating of water in accordance with the availability of solar energy and time of day to provide sufficient hot water for average usage. 
     
     
         6 . The water heater of  claim 1  wherein water flows from a top zone of one compartment to a lower zone of another compartment. 
     
     
         7 . The water heater of  claim 1  wherein the separation walls between compartments provide good heat insulation. 
     
     
         8 . The water heater of  claim 1  wherein the heat source functions according to implementation  1 a. 
     
     
         9 . The water heater of  claim 1  wherein the heat source functions according to implementation  1 b. 
     
     
         10 . The water heater of  claim 1  wherein the heat source functions according to implementation  1 c. 
     
     
         11 . The water heater of  claim 1  wherein the heat source functions according to implementations  1 a and  1 b. 
     
     
         12 . The water heater of  claim 1  wherein the heat source functions according to implementations  1 a and  1 c. 
     
     
         13 . The water heater of  claim 2  wherein water flows from a top zone of one compartment to a lower zone of another compartment. 
     
     
         14 . The water heater of  claim 3  wherein water flows from a top zone of one compartment to a lower zone of another compartment. 
     
     
         15 . The water heater of  claim 4  wherein water flows from a top zone of one compartment to a lower zone of another compartment. 
     
     
         16 . The water heater of  claim 5  wherein water flows from a top zone of one compartment to a lower zone of another compartment. 
     
     
         17 . The water heater of  claim 2  wherein the separation walls between compartments provide good heat insulation. 
     
     
         18 . The water heater of  claim 3  wherein the separation walls between compartments provide good heat insulation. 
     
     
         19 . The water heater of  claim 4  wherein the separation walls between compartments provide good heat insulation. 
     
     
         20 . The water heater of  claim 5  wherein the separation walls between compartments provide good heat insulation.