Method for operating a power plant for generating energy, comprising at least one stationary internal combustion engine (1) and a district heating system (20) connected to the at least one internal combustion engine (1) in a heat exchange relationship, wherein the at least one internal combustion engine (1) is configured to deliver a mechanical power by burning a fuel, wherein on the one hand the at least one internal combustion engine (1) is cooled and on the other hand heat is supplied to the district heating system (20) through a heat exchange between the district heating system (20) and the at least one internal combustion engine (1) and wherein at least one additional cooling device (12) is provided,
wherein the cooling of the at least one internal combustion engine (1) is effected—at least partially—using the at least one additional cooling device (12) when a transient performance requirement for the at least one internal combustion engine (1) occurs.

There is herein described energy storage systems. More particularly, there is herein described thermal energy storage systems and use of energy storable material such as phase change material in the provision of heating and/or cooling systems in, for example, domestic dwellings.

The present invention provides for a combined heat and power system including at least one engine, operatively coupled to a generator, having at least one first heat source adapted to provide a first thermal energy output at a first temperature range, and at least one second heat source adapted to provide a second thermal energy output at a second temperature range, at least one first heat exchanger, operatively coupled to said at least one engine, and adapted to selectively receive and transfer at least a portion of any one or all of said first thermal energy output and said at least one second thermal energy output; and a dynamically adaptive heat storage system.

Provided is a cogeneration system that includes a plurality of fuel cell devices capable of supplying heat and power to a heat load and a power load and a control device connected to the fuel cell devices. The control device determines an operation mode on the basis of at least one of a heat demand value and a power demand value. The control device controls a power generation efficiency and a heat recovery efficiency by controlling the fuel cell devices on the basis of the operation mode determined.

A water heater can include a housing and a heating system disposed within the housing, where the heating system is configured to heat a fluid. The water heater can also include a switch coupled to the heating system, where the switch operates between a first position during normal operations and a second position during an outage. The water heater can further include a primary power source coupled to the switch, where the primary power source is configured to provide primary power to the heating system through the switch during the normal operations. The water heater can also include an uninterruptible power supply (UPS) coupled to the switch, where the UPS is configured to provide reserve power to the heating system through the switch during the outage, and where the UPS is integrated with the housing.

A gas-fired instantaneous water heater including a thermoelectric generator (TEG) and a heat pump that is powered by the TEG to improve efficiency compared to existing water heaters. Water to be heated is circulated through the heat pump, TEG heat exchanger, and primary heat exchanger to produce a stream of heated water. An adjustable firing rate permeable matrix radiant burner is included, in which natural gas and air are combusted to produce combustion products, including heat. The combustion products are condensed in a condensing system to produce cooled and dry exhaust gas.

A heated water device is disclosed. The heated water device includes a cold water tank configured to receive cold water from a cold water source and a hot water tank configured to receive water from a hot water source and discharge water to the cold water source. The heated water device includes a pump configured to selectively pump water from the hot water source and to the hot water tank and a valve configured to selectively permit water to flow from the hot water tank to the cold water source. The heated water device includes a thermoelectric generator configured to generate electrical energy from a water temperature differential between cold water in the cold water tank and heated water in the hot water tank.

Apparatus and methods for a gas furnace are disclosed. The gas furnace includes a variable combustion control which monitors the temperature of the burner and modifies one of the amount of combustion air supplied and the amount of gas fuel supplied to the mixing chamber. The described systems can dynamically accommodate differences in air quality and gas fuel supply to provide an optimum BTU output irrespective of differences in geographic location of usage. The gas furnace can include a dynamic response unit which predicts an optimum rate of heating to maintain a target room temperature, thereby preventing unnecessary shut down and costly re-ignition sequences, and maintaining the gas furnace at an optimum BTU output level.

A water heater can include a housing and a heating system disposed within the housing, where the heating system is configured to heat a fluid. The water heater can also include a switch coupled to the heating system, where the switch operates between a first position during normal operations and a second position during an outage. The water heater can further include a primary power source coupled to the switch, where the primary power source is configured to provide primary power to the heating system through the switch during the normal operations. The water heater can also include an uninterruptible power supply (UPS) coupled to the switch, where the UPS is configured to provide reserve power to the heating system through the switch during the outage, and where the UPS is integrated with the housing.

A heated water device is disclosed. The heated water device includes a cold water tank configured to receive cold water from a cold water source and a hot water tank configured to receive water from a hot water source and discharge water to the cold water source. The heated water device includes a pump configured to selectively pump water from the hot water source and to the hot water tank and a valve configured to selectively permit water to flow from the hot water tank to the cold water source. The heated water device includes a thermoelectric generator configured to generate electrical energy from a water temperature differential between cold water in the cold water tank and heated water in the hot water tank.