The present invention relates to a method and apparatus for transferring heat energy from a waste-liquid, wherein the apparatus (100) comprises at least one heat exchange element (107) for transferring heat energy from waste liquid in a first container (101) to a first target fluid, at least one heat pump element (111) for transferring heat energy from waste-liquid transferred from the first container to the further container (102), at least one selectively operable exit-valve element (115) for selectively providing at least one fluid communication path for allowing waste-liquid to exit from the further container, and at least one controller element for selectively operating the heat pump element to transfer heat energy from waste-liquid in the further container to a further target fluid and/or for selectively operating the at least one selectively operable exit-valve element.

Provided are a heat exchange method of tap water using a heat exchanger, and the heat exchanger. The content of residual chlorine in the tap water is about 2 ppm or more, the heat exchanger comprises a plurality of heat plates, which comprise ferritic stainless steel, and copper brazing configured to couple the heat plates, and the ferritic stainless steel contains less than about 0.5 wt % of nickel, about 0.1 wt % to about 2 wt % of copper, and about 0.03 wt % or less of carbon.

An electric power system is disclosed herein. The electric power system may manage and store electric power and provide uninterrupted electric power, derived from a plurality of electric power sources, to an electric load. The electric power system may contain an energy storage unit and generator assembly. The electric power system may connect to a power grid and renewable energy sources, and may charge the energy storage unit using the power grid, renewable energy sources, and/or generator assembly. The electric power system may be configured to determine load power usage and environmental factors to automatically and continuously modify a charging protocol to, for example, provide high efficiency and/or self-sufficiency from the power grid. The electric power system may operate entirely off-grid and may provide electricity to the load without interruption to power.

A gray water heat recovery apparatus has first and second passes in counter-flow orientation. The hot side is gray water. The cold side is fresh water. It extracts heat from the gray water. The fresh water is carried in tubing bundles in series immersed in gray water sumps in a unitary cylindrical plastic, mild steel, stainless steel or copper pipe section that defines multiple flow passages. Both ends of the fresh water bundle assembly extend from the same upper end pipe closure, without a pressurized line wall penetration in the walls of the pipe. There is a non-electrically conductive barrier between the fresh water and gray water flow paths. The apparatus has a leak detection circuit and co-operable bypass valves. The lower manifold has gray water passages between the centering ears. The entire assembly is enclosed in a unitary external housing with axially accessible connection fittings.

An apparatus for heating water has a tank for storing water and an air conditioning system that defines a refrigerant flow path through which refrigerant flows. The refrigerant flow path passes through the heat exchanger so that refrigerant heat is contributed to the tank. A control system controls operation of the water heating apparatus.

A refrigeration system includes at least one refrigeration circuit 2. The refrigeration circuit 2 includes a compressor 10, a first heat rejecting heat exchanger 6, a second heat rejecting heat exchanger 8, an expansion valve 12 and a heat absorbing heat exchanger 4. The refrigeration circuit 2 further includes a heat recovery control valve 14 for controlling flow of the compressed refrigerant fluid between the first heat rejecting heat exchanger and the second heat rejecting heat exchanger. The first heat rejecting heat exchanger 6 is for receiving compressed refrigerant fluid from the compressor 10 and exchanging heat between the compressed refrigerant fluid and a second fluid to increase the temperature of the second fluid, for example for heat recovery by heating water. The second heat rejecting heat exchanger 8 is for receiving the compressed refrigerant fluid and exchanging heat with ambient air to cool the compressed refrigerant fluid.

A heat exchange system for transferring heat energy to control the temperature of a building comprising: a first heat exchanger having a first and second inlet and a first and second outlet wherein waste water flows through said first inlet of said first heat exchanger and out said first outlet while a water supply flows through said second inlet through said first heat exchanger and out said second outlet so as to transfer heat energy between said waste water and said water supply; and a second heat exchanger having a first and second inlet and a first and second outlet wherein domestic water flows through said first inlet, through said second heat exchanger and out said first outlet while said water supply from said second outlet of said first heat exchanger flows through said second inlet, through said second heat exchanger and out said second outlet so as to further transfer heat energy between said domestic water and said water supply from said second outlet of said second heat exchanger and control the temperature of said building.

A system for exchanging electrical energy between an electrical energy source and an electrical energy store of a vehicle, wherein the system includes an electrical connection, at least one electronic component, and a cooling device having a heat transfer medium, wherein, when the electrical energy store of the vehicle is connected to the electrical connection and electrical energy is exchanged between the energy source and the electrical energy store via the at least one electronic component, the heat transfer medium of the cooling device is designed to provide heat, which arises during the exchange of electrical energy in the system, to a consumer of the heat, which is coupled to the system and is arranged in a building.

A hot water supply system includes a water supply pipe for supplying cold water, a hot water supply pipe for supplying hot water heated by a hot water supply device, a drain pipe for draining waste water, a heat exchange device for heating cold water supplied from the water supply pipe using the waste water, and a flow rate control mechanism for controlling, when supplying warm water obtained by mixing cold water heated by the heat exchange device and hot water heated by the hot water supply device, the flow rate of the cold water and the flow rate of the hot water so as to maintain the temperature of the warm water.

Provided is a water heater including a burner that receives a supply of combustion air from a fan, a heat exchanger having a heat transfer tube, and a combustion chamber case in which a combustion chamber of the burner is formed in the interior thereof and which is to be capable of guiding combustion gas generated by the burner to the heat exchanger. The water heater further includes a unit case that surrounds the combustion chamber case, and a region on the outside of the combustion chamber case within the unit case serves as an air pressure chamber having a higher pressure than the combustion chamber. Thus, combustion gas leakage to the outside can be prevented or suppressed appropriately by means of a simple configuration.