324results about "Combined heat and power systems" patented technology

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.

A power distribution/generation system is disclosed for supplying electrical power to a number of sites (32, 33, 34), one or more of which has a generator (53, 1) such as a Stirling engine (1) which is capable of generating electrical power. The generators (53, 1) are linked together on a local network that is connectable to an external power grid (31). A controller (35) can hold the distribution of power so that a site is supplied with electrical power from the local network if its power demand exceeds the power generated by the generators in that network. However, if the total power demand of all the sites in the network exceeds the total power available from the generators in that network, then the controller (35) causes power to be drawn from the grid (31) instead.

This invention provides a system and method for cogeneration of electric power and building heat that efficiently interfaces a liquid-cooled electric power generator with a multi-zone forced hot water (hydronic) space heating system. The system and method utilizes an electric generator with an electric output capacity (kW) that is near the time-averaged electric power consumption rate for the building and with a heat generation capacity that is useful for meeting building heating needs. This generator is operated as the priority source of heat for the building, but normally only when there is a demand for heat in building, with the intent of running the generator for long periods of time and generating a total amount of electric energy (kWhs) that is significant in comparison to the total electric energy consumption of the building over time. The actual onsite time-variable power demand (kW) is met by a combination of the cogenerated electric power produced on site and quantities of electric power from the public electric power grid or another external power source. Hence, useful electric power is generated on site as a by-product of the required generation of heat for space or water heating. The generator is run at a speed/operating condition that is appropriate to maintaining a long operational life.

Systems and methods are disclosed for controlling photovoltaic cell temperature by removing excess thermal energy from photovoltaic cells in a photovoltaic module and using the excess thermal energy for heating or to drive a heating and/or cooling apparatus. In one instance, the heating and/or cooling apparatus is an absorption chiller. A generator of the absorption chiller can either be thermally connected to the photovoltaic module or can be heated by transferring the thermal energy from the photovoltaic module to the absorption chiller via a heating fluid such as water.

A solar photovoltaic water heating system is disclosed having a photovoltaic solar panel array, a storage tank containing water to be heated, a resistance heating element in the water to be heated. The water heating system matches the load resistance of the resistance heating element to the power that is available from the photovoltaic solar panel array in order to maximum energy transferred to the water in the storage tank.

The microturbine engine that is typically utilized to power an electrical generating system and/or boiler, chiller and the like includes a second boiler and a by-pass system for providing heated water at two different levels or where one of the boilers provides steam. The turbine exhaust is utilized as the heat transport medium and is directly connected to one of the boilers while the other is connected to the recuperator. The system can optionally provide cooling to the electrical and electronic components of the system by providing a water circuit for leading water into the electric and electronic components prior to feeding the boilers. The system is designed to assure that the delta heat difference between the medium being heated and the waste heat of the turbine is sufficient so that the heat exchange will be done efficiently.

A system for simultaneously producing electricity, water at a first temperature, water at a second temperature greater than the first temperature, and water at a third temperature greater than the second temperature. The system can also optionally simultaneously provide a refrigerating fluid at a first evaporation temperature, and the refrigerating fluid at a second evaporation temperature.

A thermal source provides heat to a heat engine and or one or more thermal demands, including space and water heating and heat storage. Additionally the output of the heat engine may be used for local in situ electricity needs, or directed out over the grid. A system controller monitors conditions of the components of the system, and operates that system in modes that maximize a particular benefit, such as a total accrued desired benefit obtained such as reduced electricity cost, reduced fossil fuel use, maximized return on investment and other factors. The controller may use past history of use of the system to optimize the next mode of operation, or both past and future events such as predicted solar insolation.

A distributed solar power generation and hot water supplying system includes: a photovoltaic power generation self-service sun tracking system, an inverter, a controller, a storage battery, a heat-exchanging water tank and an electric heater provided therein, wherein a solar battery and a solar collector are mounted on the photovoltaic power generation self-service sun tracking system, an electricity output terminal of the photovoltaic power generation self-service sun tracking system is respectively connected to an inversing input terminal of an inverter and a surplus power supplying input terminal of a controller; an MCU-controlled power output terminal of the inverter is respectively connected for off-grid power consumption or grid-connected power generation, and to an inversing output terminal of the controller; a charging/discharging control output/input terminal inside the inverter is connected to an input/output terminal of the storage battery and a storage battery power supplying input terminal of the controller.

A heat pump liquid heater for heating a liquid comprising: a heat pump; a liquid tank in heat communication with the heat pump, wherein the liquid tank comprises the liquid; and at least one metal condenser tube immersed into the liquid, wherein the metal condenser tube forms at least one coil. The metal condenser tube has a flattened double-tube configuration and a cross-section defined by concentric ovals such that at least a portion of the concentric ovals is in contact with one another thereby minimizing space between the flattened double-tubes. The heat pump comprises a tube-in-tube heat exchanger and a compressor, wherein the tube-in-tube heat exchanger recovers heat from refrigerant returning from the liquid tank and transfers the recovered heat to refrigerant going to the compressor thereby superheating the refrigerant.

A simple solar heating system incorporates a heat dissipater into a heat exchange circuit for bypassing solar collectors when either the temperature or the pressure in the heat exchange circuit exceeds preset limits. In the absence of electric controllers, fluid in the heat exchange circuit is caused to bypass the solar collectors using a valve which is controlled by either the temperature or pressure of the fluid. A solar photovoltaic panel energizes a circulating pump for increasing the rate of pumping as more solar energy is available at the PV panel and decreasing the rate as solar energy decreases.

Direct current solar electric heating elements can be powered by an array of photovoltaic panels. The direct current voltage can be low or high with proper electrocution protection. Insertable immersion heating elements can be placed into any existing, gas, propane or electric hot water tank, cooking pot or hot tub. Heating elements in air can also be used for heating ovens, range cook tops and sauna heaters. The output of the photovoltaic panel is interfaced to the electric heater element via either direct connection or using a load-matching controller which maximizes the power delivered to the heater under all sun conditions. The maximum heater temperature is regulated by a thermostat.

A cogeneration system includes a first cooling device disposed in a cooling water circulation path extending between an engine and a waste-heat heat exchanger, and a second cooling device disposed in a hot water circulation pipe extending between a hot water storage tank and a hot air heater. The first cooling device is activated to cool cooling water when the temperature of hot water stored in the hot water storage tank exceeds a first predetermined value, and the second cooling device is activated to cool the hot water when the temperature of hot air inside the hot air heater exceeds a second predetermined value.

A fluid heater is disclosed and which has a heater, pump, and a plurality of temperature sensors which are electrically coupled with first and second temperature controlled relays, and wherein the fluid heater is operable to maintain a source of fluid used by an object of interest within a predetermined temperature range and further, is operable under given temperature conditions to discontinue operation so as to protect the object of interest and the heater from becoming damaged through overheating of the fluid which is utilized by same.

A heat pump hot-water supply system includes a heat pump hot-water supply device, an electricity storage device, and a control device. The control device determines an operating time zone of the heat pump hot-water supply device based on power conversion efficiency of the electricity storage device, coefficients of performance of the heat pump hot-water supply device of a current day and a next day, and an electricity rate structure of a commercial power system.