Method for indirectly preheating a fluid upstream of a furnace, wherein the fluid is preheated by indirect heat exchange with fumes discharged from the furnace through a medium in a chamber, and wherein the flow rate of the medium in the chamber is adjusted on the basis of at least one of the following temperatures: the temperature of the discharged fumes, the temperature of the medium in the chamber, the temperature of the preheated fluid, and the temperature of the wall separating the discharged fumes from the medium in the chamber.

A combined heating and power system is configured to generate energy as well capture a large percentage of energy that would otherwise be lost using components, including heat transfer components, embedded within a vessel to transfer energy in the form of heat to liquid within the vessel.

A combined heat, cooling and power system is configured to generate energy as well capture a large percentage of energy that would otherwise be lost using components, including heat transfer components, embedded within a vessel to transfer energy in the form of heat to liquid within the vessel.

A combined heat, cooling and power system is configured to generate energy as well capture a large percentage of energy that would otherwise be lost using components, including heat transfer components, embedded within a vessel to transfer energy in the form of heat to liquid within the vessel.

A microscale energy cogeneration system comprising at least one micro/nano-turbine for converting fuel into mechanical energy and a generator for converting mechanical energy produced by the micro/nano-turbine into electrical energy in the range of 1 to 5 kWh. Compressed air passes through a cold side of a heat exchanger. The compressed cold air and fuel delivered to a combustion chamber drives the turbine. At least one heat exchanger receives high temperature exhaust gas from an exhaust passage downstream from the micro/nano-turbine for heat transfer. The heat exchanger can be used to heat water and/or air of a house. A water heating system can be coupled to the heat exchanger for converting tap water into potable hot water and/or converting cool air into hot air. The portable micro/nano-turbine set can be scaled up by interconnecting several units to a network for balancing out the energy demand of multiple users.

A reverse combustion type combustion apparatus (1) includes a combustion section (2) that combusts fuel in a downward direction, heat exchangers (4, 5) disposed under the combustion section (2), and an exhaust box (6) disposed under the heat exchangers (4, 5). The exhaust box (6) is a molded product made from a synthetic resin material; the exhaust box (6) includes an opening portion (30) for introduction of combustion exhaust gases generated by an upper portion, a fixing portion (33) for fixing the heat exchanger (5), and an inclined bottom portion (35) that collects condensed water generated by the heat exchanger (5); and, at the lower end portion of the exhaust box (6), at least three legs (40) are integrally formed and make the exhaust box (6) stand up by itself.

A heat recovery system for recovering waste heat from exhaust gases that are expelled through a flue that are generated as a byproduct from a heating system, comprises a venting arrangement that connects to the flue from the heating system and a motorized damper to direct the exhaust gases from the flue through the venting arrangement to an intake plenum. The intake plenum directs the exhaust gases to a heat exchanger that comprising a series of serpentine conduits between which the exhaust gases pass through. The heat exchanger is connected to exhaust plenum which is in turn connected to an exhaust fan that draws the exhaust gasses through the heat recovery system. The heat exchanger further comprises a series of inlet ports and outlet ports that add and remove coolant to the serpentine conduits at selected temperatures.

A thermodynamic boiler for exchanging (providing or drawing) heat with a heating circuit includes a thermal compressor. The thermal compressor acts on a compressible fluid and includes at least one compression stage, with an alternating bi-directional piston separating a first chamber and a second chamber, and a first fuel burner forming a heat source coupled to the first chamber. The thermal compressor uses the heating circuit as a cold source coupled to the second chamber and forms the compression function of a reversible heat pump type loop.

Method for indirectly preheating a fluid upstream of a furnace, wherein the fluid is preheated by indirect heat exchange with fumes discharged from the furnace through a medium in a chamber, and wherein the flow rate of the medium in the chamber is adjusted on the basis of at least one of the following temperatures: the temperature of the discharged fumes, the temperature of the medium in the chamber, the temperature of the preheated fluid, and the temperature of the wall separating the discharged fumes from the medium in the chamber.

A boiler system having a generally cylindrical housing or shell includes a main or fire tube with a furnace or combustion chamber extending longitudinally near the bottom of the housing and a burner to accomplish combustion within the combustion chamber. The combustion chamber opens at its rear end to furnace tube sheet, and to a first set of tubes extending longitudinally of the boiler. The first set of tubes extends to and through the rear tube sheet of the boiler to a turnaround space, which transitions to a second set of tubes located above the combustion chamber and first set of tubes to generally span a length extending from the rear tube sheet of the boiler to the front tube sheet. The boiler system as disclosed has a reduced size while maintaining efficiency in steam and hot water applications.