A system for heating water includes an interior region, a first heat source including a gas burner configured to generate combustion gases; a second heat source including an electric heating element; a temperature or flow or pressure sensor positioned to directly or indirectly sense a temperature or a flow or a pressure of water contained in the interior region; and a mechanical and/or electrical controller coupled to the temperature or flow or pressure sensor, the first heat source, and the second heat source. The controller actuates the first heat source by firing the gas burner in response to a first signal from the temperature or flow or pressure sensor, and/or actuates the second heat source by actuating the electric heating element in response to a second signal from the temperature or flow or pressure sensor.

A water heating system includes a tank that retains water, a heat pump that heats the water in the tank, and a water heater that heats supplied water by combustion heat of fuel gas. In the water heating system, a tank use mode in which the water in the tank is mixed with tap water and supplied to a plurality of using locations including a bathtub, and a hot water supply use mode in which water supplied from the tank or tap water is heated by the water heater and then supplied to the plurality of using locations are executable. The tank use mode is executable at least in a predetermined second time slot, and a capacity of the tank is set to be equal to or more than a first reference capacity and equal to or less than a second reference capacity.

An on-demand water heater (12) includes a heat exchanger (25). Water is supplied to the water heater from a water source such as a well pump (16) or other source of water. The water supplied to the water heater is treated by at least one water conditioner 18. A plurality of electrical heating elements (26, 28, 30, 32) are supplied with electrical power from rechargeable battery pack (46). At least one circuit (48) is operative to control the delivery electrical power from the battery pack to the heating elements to provide for the delivery of heated water at a set temperature from the water heater. The battery pack of the water heater is recharged from an available supply of house current electrical power. The rechargeable battery pack of the exemplary water heater also provides an auxiliary source of electrical power for other devices in circumstances when electrical power from a usual supply source becomes unavailable.

An improved ASHP having an integrated hydronic loop for thermal energy storage is provided. The hydronic loop includes a phase change material storage module to release energy capacity during peak electricity hours. The ASHP further includes an indoor air-to-refrigerant heat exchanger, an outdoor air-to-refrigerant heat exchanger. a refrigerant-to-water heat exchanger, three electronic expansion valves to control refrigerant flow, and a multi-capacity compressor with a suction line accumulator to store excess refrigerant charge. The ASHP includes at least six working modes of operation, including: (1) space cooling mode: (2) cooling energy charge/simultaneous space cooling and cooling energy charge/defrost mode: (3) cooling storage discharge mode: (4) space heating mode: (5) heating energy charge mode: and (6) heating storage discharge mode. This and other embodiments are uniquely suited for residential space cooling, space heating, water heating, and commercial applications with high water heating and space cooling demands.

A system for regulating a building energy supply and distribution installation, the installation including items of energy collection equipment, each of which is in an energy transfer relationship with a respective source; items of energy transformation equipment powered by the collection equipment; items of energy using equipment; the regulation system configured for defining, for the items of equipment, different respective activation states chosen according to parameters, for optimizing with regard to criteria. The system implements a method in the installation, with the following steps: regulation is performed by placing the items of equipment in respective activation states chosen according to demand and parameters, for the purpose of optimizing with regard to criteria; at an intervention instant of regulation, regulation takes forecasts relating to at least one of the parameters into account, the forecasts relating to a period after the intervention instant. A related installation includes the regulation system.

A gas-electric hybrid storage water heater includes a water tank, a casing, a combustion chamber, a gas control valve and an electric heating tube. The water tank is provided with a water inlet and a water outlet. The casing is arranged at an end of the water tank, and the combustion chamber is arranged in the water tank. The combustion chamber has a closed end and an open end arranged in the casing. The gas control valve is arranged in the casing, and is connected to a gas inlet pipe and a burner. The burner is configured to extend into the combustion chamber, and a side of the burner is provided with an ignition device. The electric heating tube is inserted into the water tank, and is arranged side by side with the combustion chamber.