A water heater is provided having an insulated tank having a water inlet and a water outlet, and further defining an interior volume to contain a quantity of water. A primary heating arrangement applies heat energy to the water so as to heat the water. In addition, the primary heating arrangement is configured to maintain the water during standby periods between upper and lower set point temperatures. A supplemental heating arrangement is operative to supply additional heat energy to the water in order to lessen energy usage by the primary heating arrangement during the standby periods. In accordance with a preferred embodiment, the supplemental heating arrangement includes at least one photovoltaic panel and a supplemental heating element. Control electronics are operatively interposed between the at least one photovoltaic panel and the supplemental heating element.

A water heater control system includes: a photovoltaic power generator interconnected with a commercial power supply, an electrical load circuit including a storage-type electric water heater using power from the commercial power supply and generated power of the photovoltaic power generator to perform a water heating operation of heating low temperature water to high temperature water and storing the high temperature water, and a HEMS controller limiting a water heating operation of the storage-type electric water heater by stopping or suppressing the water heating operation of the storage-type electric water heater when a power fee data for purchased power supplied to the electrical load circuit from the commercial power supply exceeds a standard monetary amount.

The integrated solar absorption heat pump system includes an absorption heat pump assembly (AHPA) having a generator, a condenser in fluid communication with the generator, an evaporator/absorber in fluid communication with the condenser and the generator, and a heat exchanger in communicating relation with the evaporator/absorber; a solar collector in fluid communication with the generator of the AHPA; a photovoltaic thermal collector in communicating relation with the evaporator/absorber of the AHPA; a plurality of pumps configured for pumping a fluid throughout the system to provide the desired heating or cooling; a power storage source, e.g., a solar battery, in communicating relation with the photovoltaic thermal collector; and a coil unit in communicating relation to the evaporator/absorber for receiving an air-stream. The absorption heat pump assembly can include an absorber and a solution heat exchanger.

In an air-conditioning system, during precooling or preheating control, a setting temperature is controlled such that a first temperature difference between the setting temperature and an indoor temperature is not less than a temperature difference at which a compressor performs operation, and the setting temperature is controlled to be changed to a target temperature when a second temperature difference between the indoor temperature and the target temperature is less than the first temperature difference. Since the compressor can be operated in the range from a low capacity to a medium capacity, operation efficiency of the air-conditioning apparatus can be increased, and the energy-saving operation with less power consumption can be realized. Since the operation capacity of the compressor can be readily suppressed with adjustment of the setting temperature, control is facilitated and the precooling control can be incorporated in various types of air-conditioning apparatuses.

A solar photovoltaic (PV) water heating system includes a tank (1.020) including at least a first heating unit (1.016) having at least first and second heating elements (1.016.1 . . . 1.016.x), at least one of which is switchable (1.014.1A . . . 1.014.1m); a PV solar collector (1.002); an inverter (1.004) adapted to convert the output from the PV collector to an alternating power supply; a modulator (1.060) to modulate the alternating power supply from the inverter; a controller (1.040) 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 PC collector.

The invention relates to a system for producing hot water, comprising a hot water reservoir, a first and a second resistance heating rod for heating the water in the hot water reservoir, a reservoir temperature sensor, and a control unit, by means of which the first resistance heating rod can be connected to a network alternating voltage source, wherein the system comprises a photovoltaic device for producing a direct voltage and the photovoltaic device can be connected to the second resistance heating rod by means of the control unit or a further control unit.

An integrated renewable energy and asset system is provided. In some embodiments, the system comprises: an existing parking lot positioned adjacent to a building structure, wherein the existing parking lot has an associated pattern; bore holes that are formed into the existing parking lot, wherein the bore holes are organized based on the pattern of the existing parking lot; vertical columns inserted into at least a first portion of the bore holes, wherein: crossbeams are installed on an upper portion of a vertical column to form a support structure; and a canopy is connected to the crossbeams, wherein the canopy is formed from multiple attached photovoltaic modules and thermal tubes are integrated with the photovoltaic modules; geothermal tubes that capture thermal energy are inserted into at least a second portion of the bore holes, wherein each of the thermal tubes and each of the geothermal tubes is connected to a geothermal heat pump and wherein each of the thermal tubes is connected to the geothermal heat pump; and a hardware processor that is configured to: receive sensor information from sensors disposed on the canopy; determine whether to direct at least a portion of the thermal energy captured using the geothermal tubes to the solar thermal panels based on the received sensor information; and cause the heat captured using the geothermal tubes to be directed to the solar thermal panels based on the determination.

This invention provides a system and process to optimize photovoltaic (PV), grid, and other electricity in powering an electric water heater. The system comprises a photovoltaic (PV) controller coupled to a plurality of power input sources and heating elements wherein the heating elements immersed in an electric immersion heater water tank. The PV controller is further configured with control circuitry having an operating efficiency routine calculating optimal use cases from a variety of installation parameters and learned parameters to determine the appropriate power input source and switch between sources accordingly.

A heating system includes a heat pump that provides heat to a major fluid circuit and a minor fluid circuit for performing different heating operations. The system includes a power source having a variable cost and a controller configured to regulate flow of the major and minor fluid circuits to perform the heating operations. The controller is configured to receive information regarding the variable cost of the power source and distribute flow between the major and minor fluid circuits to perform the heating operations to minimize the electricity cost. The combined enhanced demand regulation and enhanced output regulation amplifies the total heat output and power consumption while permitting greater use of a power source of varying cost (e.g. PV)thereby minimizing overall daily operating cost.

A system for space heating or cooling a heated space includes a heat pump including a refrigeration circuit for transferring heat between a heat source and a heat load for heating and cooling operations. A controller controls the heat pump to perform the heating and cooling operations. A user interface receives user inputs, wherein the user inputs include an indication of discomfort based on temperature. The controller creates a profile for a minimum comfortable temperature level and a maximum comfortable temperature level, and the controller controls the heat pump to perform the heating and cooling operations in accordance with the profiles for the minimum and maximum comfortable temperature levels. The controller may generate an optimized heat demand plan in accordance with predictions of outdoor and indoor temperature, cost, and demand. The plan is optimized to cost-effectively maintain the temperature of the heated space within the comfortable temperature range defined by the profiles.