A system for heating a first fluid flow from a first temperature to a second temperature, the system including a hot water supply line for receiving the first fluid flow at a first end and exhausting the first fluid flow at a second end; and a heating system including a heat engine, a thermal battery and a heat exchanger, wherein the thermal battery is configured to be replenished at a point of heat transfer by the heat engine and the hot water supply line is configured to receive heat from the thermal battery via the heat exchanger to elevate the temperature of the first fluid flow from the first temperature to the second temperature.

A solar photovoltaic (PV) water heating system includes a tank including at least a first heating unit having at least first and second heating elements, at least one of which is switchable; a PV solar collector; an inverter adapted to convert the output from the PV collector to an alternating power supply; a modulator to modulate the alternating power supply from the inverter; a controller adapted to control the modulator and the switching of the or each switchable heating element; wherein the controller is adapted to control the modulator and the switchable heating elements to maximize the energy drawn from the PV collector.

Systems and methods for integrating photovoltaic (PV) energy into water heater systems are disclosed. The disclosed technology includes determining whether a current water temperature is less than a first PV heat point that is greater than a normal heat point, and if so, outputting instructions for PV energy to be transferred from a PV system to a heating device of the water heater. If the current water temperature falls below a second PV heat point that is less than the normal heat point, the disclosed technology includes outputting instructions for energy to be transferred from a utility system to the heating device.

A solar-powered two-bed adsorption chiller which can operate after sunset when the solar radiation intensity becomes zero. Rechargeable solar-powered batteries (SPBs) are connected to a flat-plate solar collector (FPSC). The photoelectric charges are directed from FPSC to a solar charge controller (SCC) which acts as a charge amplifier thus magnifying the total charge before it is finally collected inside the SPB for future use. The SPB is in turn connected to a resistance heating wire (RHW) which is immersed inside the HWST.

A solar assisted water heating system for an electric water heater is provided to include a water guiding unit, a solar conversion unit, a radiant energy collection unit, and a pump. When electrical energy from the solar conversion unit is being applied to the pump, the water is driven by the pump to flow into the water guiding unit so as to be heated by the radiant energy collection unit which absorbs sunlight.

The disclosed technology relates to a solar water heating system including a tank configured to store heat transfer fluid, a solar collector in fluid communication with the tank, and a pump system in fluid communication with the tank and the solar collector. The pump system can include a first pump, a second pump, and a valve assembly. The valve assembly can direct the heat transfer fluid from an outlet of the first pump to the solar collector when the first pump is operating and can direct the heat transfer fluid from an outlet of the second pump to the solar collector when the second pump is operating. The first pump and the second pump can transfer the heat transfer fluid from the solar collector back to the tank when the first pump and the second pump are not operating.

Appliances, such as hot water heaters, hot water heater controllers, and methods of operating such hot water heaters, that take into consideration the availability and capacity of alternative energy sources so that additional efficiencies can be realized by sensing the availability of an alternative energy source and adjusting the control algorithms used to control the use of the available electric power is provided.

Provided herein are various systems and methods (i.e., utilities) broadly directed to the generation of hot water using energy derived from renewable energy sources as an alternative to or in conjunction with another power source (e.g., fossil fuel-based energy from a utility provider, an underperforming solar/wind/wind system, etc.). In the various aspects, these utilities are directed to the retrofitting of existing water heaters with electrical heating elements that are connectable to a renewable source of electrical energy. While primarily discussed in relation to retrofitting existing water heaters, various aspects are applicable to OEM manufactured systems. Further, various control methods are provided that allow for enhancing the efficiency of hot water generation, net metering, and/or the generation of renewable energy credits.

A solar thermal assisted water heating system includes a thermal collector comprising a plurality of fluid channels configured to collect heat from a surface of a photovoltaic module, a drain-back tank coupled to the thermal collector, a first pump coupled to the drain-back tank and configured to pump fluid from the drain-back tank to the thermal collector, a first heat exchanger configured to receive fluid from the thermal collector, a heat pump coupled to the first heat exchanger and configured to remove heat from the fluid and heat water with the removed heat, and a controller configured to control the first pump and heat pump. The system may include a photovoltaic module and a hot water tank. These systems improve the efficiency of water heating, and the drain-back tank may serve as a thermal battery that stores heat and provides the stored heat when environmental temperatures decrease.

A circulation pump assembly (2) includes an electric drive motor (6) and a control device (10) integrated into the circulation pump assembly (2). At least one internal temperature sensor (16) is arranged in the circulation pump assembly (2) and detects the temperature of the medium delivered by the circulation pump assembly (6) and issues a corresponding temperature signal (42) to the control device (10). The control device (10) is configured, on the basis of the temperature signal (42) of the internal temperature sensor (16), to approximately determine the temperature of the liquid in a liquid storage means (26) which is connected to the circulation pump assembly (2) via a heating circuit (28).