Systems and methods are disclosed for exchanging thermal energy between a drain liquid and a source liquid for heating or cooling of the source liquid. One method for heating a source liquid may involve transferring heat from a drain liquid using a heat pump. A system may include a refrigerant, a source liquid and a drain liquid, two or more heat exchangers that facilitate an exchange of thermal energy, and a means for transporting the refrigerant.

A method, apparatus and system for fluid heat recovery, more commonly known as a heat exchanger, transfers heat ordinarily lost down a drain to preheat incoming fluid, so that heating systems use less energy to heat incoming fluid. The fluid heat recovery apparatus includes a helical fluid outflow pipe with discharge fluid traveling within it, and a fluid inflow tube embedded within helical channel depressions and between the helical ridge fins of the fluid outflow pipe that contacts the fluid inflow tube outer walls to the surrounding fluid outflow pipe outer wall helical channel depressions and helical ridge fins, and connects to fluid supply lines, thereby transferring heat to incoming fluid that flows in a counter current, then parallel, then counter current direction with respect to the helical fluid outflow pipe flow.

Recovery system for the recovery of thermal energy from waste water from building, which system comprises a heat pump adapted to absorb thermal energy from a non-freeze liquid circulating through the heat pump and arranged to deliver thermal energy to water flowing through the heat pump, a heat exchanger device that is in contact with said waste water, and a pipeline system disposed between the heat pump and the heat exchanger device, and in which non-freeze liquid can circulate. The heat exchanger device is designed so that the non-freeze liquid passes through the heat exchanger device, whereby the non-freeze liquid is able to absorb thermal energy from the waste water. Further, the system comprises a collector tank, and a pipeline system for supplying waste water to the collector tank. The heat exchanger device is disposed in the collector tank, wherein the non-freeze liquid can absorb thermal energy from waste water in the collector tank.

A free-standing Energy Recovery System enables sanitary recovery of thermal energy with heat transfer from hot waste effluent to incoming domestic water. The source of the effluent may, for example, be conventional commercial ware-washing, clothes washing equipment, pasteurization and other industrial processes.

This application discloses an advanced design method for customized RCP, (cRCP), with one or more made-to-order reinforcement cages supporting one or more wall-encapsulated heat-exchange channels, cast with special-batch (SB) concrete having additions of fine-disperse CaCO.sub.3 and particular polymer fibers; the resulting Single- and DoubleEPipe sections especially adapted for heat exchange with pipe-internal wastestreams and/or groundwater and including provisions for an optional graywater accumulator for efficient recapture of both water and energy.

A method for controlling ozonation in a water supply system including an ozonator, a controller functionally connected to the ozonator, a flow meter configured for detecting a flowrate through the water supply system, a valve configured for turning on or off of the water supply system, the method including using the controller for; determining at least one event from flowrate data of the flow meter over a time period of a plurality of days, the at least one event including a time span of a day in which the flowrate remains below or at a threshold value over the time span of a day within each day of the plurality of days; determining overlaps of the at least one event of all days within the time period; determining a frequency of the overlaps of the at least one event over the time period and determining a requirement for ozone.

A system and method for providing hot water to a point of use such as a shower. Waste warm water from said point of use passes through a heat exchanger, where it initially warms incoming mains water, typically to about 34 C. The initially warmed water is heated to its final temperature, typically about 42 C., in a smart boiler. The smart boiler, which typically has a volume of about 40 liters, comprises two chambers with a flexible barrier therebetween. Each chamber is separately heated as needed. Hot water is drawn from one of the two chambers; simultaneously, the other chamber fills with initially warmed water and is heated to its final temperature. When the volume of water in the chamber from which water is being drawn reaches a minimum, the system begins to fill that chamber and to draw water from the other one.

A liquid heating appliance for heating water or other liquids, suitably to a target temperature of from 55 C. to around boiling point, includes a primary heat chamber or body (heat source chamber) that is thermally insulated and which in use contains a high thermal density heat storing liquid or solid; and a secondary chamber alongside the primary chamber through which a liquid to be heated is passed in use. The appliance has a heat transfer feature to selectively transfer thermal energy from the heat-storing liquid or solid to the liquid to be heated in the secondary chamber. The secondary chamber is preferably a conduit through which the liquid to be heated is able to flow and the thus heated liquid can be delivered to a tap as hot water for a range of uses. Water may also be heated for a central heating system for space heating.

An apparatus and method for recovering heat from a liquid medium, including a heat exchanger having heat exchanger cells, which are thermally separate from each other, for receiving the liquid medium, each of the cells has a sensor for determining temperature of the liquid medium located therein; a pipeline for conducting drinking water and/or heating water, which pipeline extends through at least one of the cells; a supply line wherein the liquid medium is conducted; controllable flaps through which the liquid medium can be selectively fed from the supply line to the cells; a sensor for measuring temperature of the liquid medium in the supply line, the flaps are controlled in an open-loop and/or closed-loop manner such that the liquid medium is supplied from the supply line to the heat exchanger cell that has a current temperature which is the least colder than the gray water in the supply line.

A grey water heat recovery apparatus is disclosed in which heat is transferred between a grey water stream and a fresh water stream. The apparatus comprises: a grey water flow path leading from a source inlet to a drain outlet; a plurality of heat exchangers arranged in said grey water flow path; a separator arranged upstream of said heat exchangers, arranged to separate grey water from the source inlet into a plurality of parallel sub-paths, each sub-path being lead to one of the heat exchangers; and a collector arranged downstream of said heat exchangers, arranged to reassemble the grey water from the sub-paths into a single flow path. Each heat exchanger comprises a grey water tube extending from the separator to the collector, and an outer tube surrounding at least a part of the grey water tube, the outer tube defining an annular space around the grey water tube. A fresh water flow path formed within the annular spaces around the grey water tubes in the heat exchangers has a flow direction being opposite to the flow direction of the grey water.