Patent Description:
Thermally activated heat pumps (such as absorption or adsorption cycles, collectively sorption) can provide space or water heating and space cooling or refrigeration. Cycle efficiencies (coefficient of performance or COP) range from <NUM> to greater than <NUM> for cooling, and <NUM> to greater than <NUM> for heating. Document <CIT> discloses a cogeneration system in which waste heat generated from a drive source such as an engine is used in at least one of a compression type air conditioner and an absorption type air conditioner to provide cooling/heat capacity. The cogeneration system includes a generator, a drive source, a compression type air conditioner, an absorption type air conditioner, and a waste heat recoverer adapted to recover the waste heat of the drive source, and to supply the recovered waste heat to at least one of the compression type air conditioner and the absorption type air conditioner.

Due to the very high heating efficiencies, fossil fuel-fired (gas, propane, oil, etc) sorption heat pumps are very attractive and environmentally friendly alternatives for conventional fuel-fired heating equipment, such furnaces or boilers, are limited to COPs less than <NUM>. For heating, fuel -fired sorption heat pumps also out-perform vapor compression cycle heat pumps driven by electrical power, especially at outside ambient temperatures less than <NUM>°F (<NUM>).

However, for cooling, the efficiency of vapor compression cycles is much higher than sorption cycles. Even though sorption heat pumps can be reversible (to provide either heating or cooling), the low cooling efficiency results in a negative economic payback during cooling season for the end-user compared to using a conventional electric vapor compression air-conditioner. In addition, the extra components required to make the sorption system reversible (compared to a heating only version) adds cost, complexity and slightly reduces the maximum heating-mode efficiency.

For a building that requires both heating and cooling, the current art (<FIG>) is to install a fuel-fired furnace or boiler (located inside the building), and an electric vapor compression cycle air conditioner (with the condensing portion located outside the building). The exact mode of delivery of the heating and cooling inside the building varies depending upon whether the system is a forced-air system or hydronic.

The only current viable option when substituting a heating-only sorption heat pump on a building that requires both heating and cooling is to install two separate pieces of equipment outside the building: <NUM>) a fuel-fired sorption heat pump and <NUM>) an electric vapor compression heat pump (<FIG>). In the case where the building uses forced-air to distribute heating or cooling, the air-handler would include a hydronic heat exchanger connected to the sorption heat pump and an evaporator (A-coil) connected to the vapor compression air-conditioner. This option requires the building owner to purchase two separate heat pumps, both of which must be installed outside the building. The cost and space required to do this may not be practical.

A heating and cooling system for a building having a hybrid fossil fuel-electric multifunction heat pump according to the invention is defined in claim <NUM>.

I provide a multi-function heating and cooling device, comprising components for an ambient air-coupled sorption heat pump cycle and vapor compression cooling cycle integrated and nested together inside an enclosure. The sorption heat pump portion may be configured to provide very high heating efficiency, while the vapor compression portion may be configured to provide high cooling efficiency. The evaporator coil for the sorption cycle and the condenser coil for the vapor compression cycle are configured to share a common ambient-air fan, saving space and cost. When space or water heating is desired, the sorption system may operate, heating a hydronic loop connected to indoor heat emitters and/or a storage water tank. When space cooling is desired, the vapor compression system may operate, connected to indoor fan-coil(s) via a hydronic or refrigerant loop. By combining the two heating-cooling systems into a single enclosure with shared components, the total installed cost and outdoor space required is reduced compared to installing separate heating and cooling systems.

A hybrid fossil fuel-electric multifunction heat pump packaged system (<FIG>) may comprise one or more of:.

When space or water heating is needed, the sorption system operates, heating the hydronic loop that is connected to heat emitters and/or a water storage tank inside the building. A fan moves ambient air through the nested or integrated evaporator/condenser heat exchanger(s), boiling the sorption cycle refrigerant flowing through the evaporator. A heat transfer fluid in the hydronic loop flows through, and is heated by, the hydronically-coupled condenser, absorber and (optional) condensing heat exchanger of the sorption system.

When cooling is needed, the vapor compression system operates, cooling the hydronic loop that is connected to cooling coils or heat exchangers inside the building. A fan moves ambient air through the nested or integrated evaporator/condenser heat exchanger, condensing the vapor compression cycle refrigerant flowing through the condenser. A heat transfer fluid in the hydronic loop flows through, and is cooled by, the hydronically-coupled evaporator of the vapor compression cycle. Optionally, cooling can be provided by the vapor compression system by directly connecting the compressor and condenser to an evaporator heat exchanger located inside the building using connecting tubes filled with the vapor compression system refrigerant.

When using the all-hydronic option, the hybrid multifunction heat pump could be configured as a "<NUM>-pipe" or a "<NUM>-pipe" system. In a <NUM>-pipe system (<FIG>), there is a single hydronic loop that is either heated or cooled based on the building requirement. Either the sorption heat pump or vapor compression heat pump operates at any given time, but in no case do they operate simultaneously. Automatic valves work to direct the heat transfer fluid in the hydronic loop through either the sorption cycle absorber, condenser and optional fossil-fuel gas condensing heat exchanger (heating mode), or through the vapor compression evaporator (cooling mode). The <NUM>-pipe option is simpler and less costly to install, but it is difficult for the sorption system to provide hot water heating during the summer when cooling is required (the vapor compression system has to shut off, interrupting cooling of the building, while the sorption system heats the water storage tank).

In a <NUM>-pipe system (<FIG>), there are two hydronic loops connected to the hybrid multifunction heat pump. One loop is dedicated to heating, and is connected to the sorption system components. The other loop is dedicated to cooling, and is connected to the vapor compression system components. The <NUM>-pipe option is more costly to install, but allows for the sorption system and vapor compression system to operate simultaneously, allowing the vapor compression system to provide space cooling at the same time the sorption system is providing water heating.

Another advantage of the <NUM>-pipe option is, if the nested or integrated ambient air-coupled evaporator/condenser heat exchanger is configured so that the ambient air first passes through the sorption cycle evaporator, and then through the vapor compression condenser, the evaporator will cool the ambient air before it flows through the condenser, allowing the vapor compression system to operate at a higher efficiency than it would if the sorption system was not operating.

Still another advantage of the <NUM>-pipe option is, if an optional hydronically-coupled refrigerant de-superheater is installed in the vapor compression system at the outlet of the compressor, the heat transfer fluid in the heating only hydronic loop could be directed using a valve to bypass the sorption system components and flow through, and be heated by, the de-superheater, and then used to re-heat a hot water storage tank. Depending on the size and service factor of the vapor compression cooling system, this may minimize the need for the sorption system to provide water heating during the cooling season, reducing energy use and the building utility bills.

Alternatively, cooling can be delivered to the building by the vapor compression system using a refrigerant loop connecting the compressor and condenser heat exchanger to an evaporator heat exchanger(s) located inside the building. With this arrangement (<FIG>), a hydronic loop is used to collect heat from the sorption system and deliver it to inside the building (similar to <NUM>-pipe arrangement previously described). The advantage of this arrangement is that cooling is provided using the more conventional direct refrigerant loop method and the sorption and vapor compression systems are able to operate simultaneously to provide cooling and water heating. This arrangement is especially advantageous for retrofit installations where heating was provided by a boiler connected to multiple hydronic radiant heat emitters located inside the building that cannot serve the dual purpose of heating and cooling due to condensation generation during cooling.

Regarding <FIG>, <FIG> and <FIG>, those familiar with the art will understand that a wide variety of configurations can be used on the inside of the building for delivering heating and cooling to the interior space, including the use of multiple air-handlers or fan-coils, radiant heat exchangers or panels located on walls, ceilings or floors, or integrated into the floors, ceilings and walls themselves. Any of these possible configurations are applicable to the hybrid fossil fuel-electric multi-function heat pump application, without loss of function.

A preferred feature of my hybrid multifunction heat pump is the nested or integrated ambient-air coupled evaporator (sorption) and condenser (vapor compression) heat exchangers. This arrangement allows the use of a shared ambient air fan, significantly reducing cost and the overall size of the heating-cooling system.

In the nested arrangement (<FIG>), the evaporator heat exchanger for the sorption cycle sits adjacent to the condenser heat exchanger for the vapor compression cycle, such that the ambient air propelled by the ambient fan flows first through one heat exchanger and then the other, but the two heat exchangers are physically separate. The physical arrangement is not limited and can be flat, U-shaped, L-shaped, cylindrical, or other geometries that provide the desired overall footprint and performance. The design of the two heat exchangers need not be identical, meaning they can use different tube and fin dimensions, materials, and configurations, optimized for the cycle they are a part of.

In the integrated arrangement (<FIG>), the evaporator (sorption) and condenser (vapor compression) functions are integrated into a single physical heat exchanger. Although the tubes for the individual functions may vary in diameter or material, they may share a common fin design. The physical arrangement is not limited and can be flat, U-shaped, L-shaped, cylindrical, or other geometries that provide the desired overall footprint and performance. By integrating the two functions (evaporator for sorption and condenser for vapor compression) into a single heat exchanger, the overall size and cost can be reduced compared to the separate (nested) arrangement. Additionally, an integrated coil would be less prone to trapping debris (leaves, grass clippings, seeds from weeds or trees) in the gap between two nested coils, which could reduce performance and efficiency.

For either the nested or integrated arrangement, the air flow configuration according to the present invention is first through the evaporator (sorption) and then through the condenser (vapor compression), although either order of flow will work acceptably. The first configuration according to the invention provides the effect that if both the sorption and vapor compression systems are running simultaneously, the evaporator will act to cool the ambient air before it flows through the condenser, allowing the vapor compression system to operate at a higher efficiency.

Referring to the drawings, <FIG> depicts a typical heating and cooling system for a building <NUM>, consisting of a fuel-fired furnace <NUM> and an electric vapor compression air conditioner <NUM>. Furnace <NUM> is located inside the building <NUM> and is connected to a return air duct <NUM>, supply air duct <NUM>, evaporator heat exchanger <NUM>, and a fossil fuel supply line <NUM>. The compressor and condenser heat exchanger for the electric vapor compression air conditioner <NUM> is located outside the building and is connected to the evaporator heat exchanger <NUM> using tubes containing refrigerant <NUM> and an electric power source <NUM>. A blower <NUM> is located adjacent to the furnace <NUM> and evaporator <NUM> to force indoor air <NUM> to be heated or cooled through the return air duct <NUM>, furnace <NUM>, evaporator <NUM> and supply air duct <NUM>. Heated or cooled supply air <NUM> delivered to the indoor space.

<FIG> depicts a heating and cooling system for a building <NUM>, comprising fuel-fired sorption heat pump <NUM> and an electric air conditioner <NUM>. The fuel-fired sorption heat pump <NUM> is located outside the building <NUM> and is connected to a hydronic heat exchanger <NUM> located within air duct <NUM> using a hydronic loop <NUM> and hydronic pump <NUM>, and fossil-fuel source <NUM>, which may be any combustible fossil fuel such as but not limited to natural gas, propane, methane, fuel-oil or bio-diesel. An electric vapor compression air conditioner <NUM> also sits outside the building <NUM>, connected to an evaporator heat exchanger <NUM> located within air duct <NUM> using a refrigerant loop <NUM>, and an electric power source <NUM>. When heating or cooling is needed, air blower <NUM> forces indoor air <NUM> through the return air duct <NUM>, hydronic coil <NUM>, evaporator heat exchanger <NUM> and supply air duct <NUM>.

<FIG> depicts a heating and cooling system for a building <NUM> according to the invention, comprising a hybrid fossil fuel-electric multi-function heat pump <NUM>. In particular, <FIG> depicts the <NUM>-pipe hydronic connection option, although the <NUM>-pipe option or hydronic-refrigerant options depicted in <FIG> and <FIG> could also be used without a loss in function. The hybrid fossil fuel-electric multi-function heat pump <NUM> is located outside the building <NUM> and is connected to a hydronic heat exchanger <NUM> located within air duct <NUM> using a hydronic loop <NUM> and hydronic pump <NUM>, fossil-fuel source <NUM> and electric power source <NUM>. When heating or cooling is needed, either the sorption or vapor compression system within the hybrid heat pump can be activated and air blower <NUM> forces indoor air <NUM> through the return air duct <NUM>, hydronic coil <NUM>, and supply air duct <NUM>. The temperature of the hydronic fluid with hydronic loop <NUM> is either hot or cold depending upon whether heating or cooling is desired.

<FIG> depicts a simple sorption heat pump cycle comprising a desorber <NUM>, condenser <NUM>, evaporator <NUM> and absorber <NUM>. High temperature heat (energy) source <NUM> (such as from the combustion of a fossil-fuel, solar, or waste heat) causes a refrigerant to boil out of a sorbent in desorber <NUM> at high pressure. The vapor refrigerant flows to condenser <NUM> through connecting line <NUM> where the refrigerant is condensed by removing heat energy <NUM>. The liquid refrigerant flows to the evaporator <NUM> through connecting line <NUM> and expansion device <NUM> in which the refrigerant pressure is reduced so it can evaporate and absorb heat energy <NUM>. The evaporated refrigerant than flows to the absorber <NUM> where it is absorbed by the sorbent which flows from desorber <NUM> to the absorber through connecting line <NUM> and expansion valve <NUM>. The refrigerant-sorbent pair flows back to desorber <NUM> through connecting line <NUM> and pump <NUM>, which pressurizes the refrigerant-sorbent pair back to the high pressure. For heating space or water in a building, heat energy <NUM> and <NUM> from the condenser <NUM> and absorber <NUM> are collected by a hydronic loop which delivers the heat energy to space heat emitters or water storage tank(s) located inside the building. Heat for evaporation of the refrigerant <NUM> in evaporator <NUM> can be from outside ambient air.

<FIG> depicts a simple vapor compression heat pump cycle comprising a compressor <NUM>, condenser <NUM> and evaporator <NUM>. Electric power <NUM> is used to power a motor <NUM> which turns compressor <NUM>. Refrigerant vapor at high pressure exits compressor <NUM> and flows to condenser <NUM> through connecting line <NUM>, where the refrigerant is condensed by removing heat energy <NUM>. The liquid refrigerant flows to the evaporator <NUM> through connecting line <NUM> and expansion device <NUM> in which the refrigerant pressure is reduced so it can evaporate and absorb heat energy <NUM>. The evaporated refrigerant than flows back to compressor <NUM> through connecting line <NUM>. For space cooling in a building, heat energy <NUM> is removed from the building interior through evaporator <NUM>. Heat energy <NUM> from the condenser <NUM> is rejected to the outside ambient air.

<FIG> depict nested evaporator <NUM> (sorption system) and condenser <NUM> (vapor compression system) heat exchangers sharing the same ambient air fan <NUM>. Both the evaporator <NUM> and condenser <NUM> comprise tubes or tube-like structures inside which the refrigerant flows, attached to and surrounded by fins <NUM>, <NUM> which assist in transferring heat from air <NUM> flowing through the two heat exchangers. The tubes can be of many possible shapes (not limited to round, flat, or oval) and fabricated from many possible materials (not limited to steel, copper, aluminum, plastic, elastomers). The fins can be of many possible shapes (not limited to flat, wavy, perforated, folded) and fabricated from many possible materials (not limited to steel, copper, aluminum, plastic, elastomers). The tube shape and geometry, as well as the fins, used for condenser <NUM> does not need to be the same as those used for evaporator <NUM>. Although <FIG> depict both the evaporator <NUM> and condenser <NUM> heat exchangers bent into a "U" shape, the two coils could be flat (not bent), round, oval, "L-shaped" or any other geometry that is desired. Although <FIG> depicts air <NUM> first flowing through evaporator <NUM> and then condenser <NUM>, the opposite arrangement is possible. Regardless, the two heat exchangers are arranged so that air is pulled through both using the same air-moving device(s) such as fan <NUM>, which may be driven by electric motor <NUM>. Fan <NUM> moves air <NUM> through both heat exchangers, where it is either heated or cooled (or both if the sorption and vapor compression systems are operating simultaneously). Although a single air-moving device <NUM> is shown, multiple air-moving devices may be used if desired, however, it is preferred if all of the air-moving devices move air through both the evaporator <NUM> and condenser <NUM> heat exchangers.

Liquid refrigerant <NUM> at low pressure from the sorption system enters evaporator <NUM> through entry tube <NUM>, flows through the circuit of tubes and fins, then exits as vapor <NUM> at exit tube <NUM>. Air <NUM> flowing around the tubes and heat transfer fins <NUM> is cooled by the evaporating refrigerant, so that air <NUM> exiting the evaporator is colder than air <NUM> entering. The circuit of tubes may consist of various arrangements commonly used for evaporator heat exchangers. Optionally, liquid refrigerant <NUM> entering evaporator <NUM> may be split and enter multiple entry tubes.

Vapor refrigerant <NUM> at high pressure from the vapor compression system enters condenser <NUM> through entry tube <NUM>, flows through the circuit of tubes and fins, then exits as liquid <NUM> through exit tube <NUM>. Air flowing around the tubes and heat transfer fins <NUM> is heated by the condensing refrigerant, so that air <NUM> exiting the condenser is hotter than air <NUM> entering. The circuit of tubes may have various arrangements commonly used for condenser heat exchangers. Optionally, vapor refrigerant <NUM> entering condenser <NUM> may be split and enter multiple entry tubes.

<FIG> depict an integrated evaporator (sorption system) and condenser (vapor compression system) heat exchanger <NUM> sharing the same ambient air fan <NUM>. Both the evaporator and condenser consist of tubes or tube-like structures inside which the refrigerant flows, attached to and surrounded by fins <NUM>, which assist in transferring heat from air <NUM> flowing through the integrated heat exchanger. The tubes can be of many possible shapes (not limited to round, flat, or oval) and fabricated from many possible materials (not limited to steel, copper, aluminum, plastic, elastomers). The fins <NUM> can be of many possible shapes (not limited to flat, wavy, perforated, folded) and fabricated from many possible materials (not limited to steel, copper, aluminum, plastic, elastomers). Although <FIG> depict the heat exchanger bent into a "U" shape, the heat exchanger could be flat (not bent), round, oval, "L-shaped" or any other geometry that is desired. According to the invention, the refrigerant containing tubes are configured so that air <NUM> first flows over all of the evaporator tubes and then condenser ; in an embodiment not according to the invention, the tubes may be interlaced so that air <NUM> flows over evaporator and condenser tubes at the same time. Fan <NUM> moves air <NUM> through the integrated heat exchanger, where it is either heated or cooled (or both if the sorption and vapor compression systems are operating simultaneously). Although a single air-moving device <NUM> is shown, multiple air-moving devices may be used if desired.

Liquid refrigerant <NUM> at low pressure from the sorption system enters heat exchanger <NUM> through entry tube <NUM>, flows through the circuit of tubes and fins <NUM>, then exits as vapor <NUM> at exit tube <NUM>. Air <NUM> flowing around the tubes and heat transfer fins <NUM> is cooled by the evaporating refrigerant, so that air <NUM> exiting the evaporator is colder than air <NUM> entering. The circuit of tubes may consist of various arrangements commonly used for evaporator heat exchangers. Optionally, liquid refrigerant <NUM> entering heat exchanger <NUM> may be split and enter multiple entry tubes.

Vapor refrigerant <NUM> at high pressure from the vapor compression system enters integrated heat exchanger <NUM> through entry tube <NUM>, flows through the circuit of tubes and fins <NUM>, then exits as liquid <NUM> through exit tube <NUM>. Air flowing around the tubes and heat transfer fins <NUM> is heated by the condensing refrigerant, so that air <NUM> exiting the condenser is hotter than air <NUM> entering. The circuit of tubes may consist of various arrangements commonly used for condenser heat exchangers. Optionally, vapor refrigerant <NUM> entering heat exchanger <NUM> may be split and enter multiple entry tubes.

<FIG> depicts a hydronic loop <NUM> of the <NUM>-pipe arrangement that connects the hybrid fossil fuel-electric multifunction heat pump to heat exchangers located inside the building for cooling and/or heating. Heat transfer fluid <NUM> (water or glycol for example) flowing in hydronic loop <NUM> returns from inside the building to the hybrid heat pump and first flows through (if in heating mode when sorption system is operating) optional condensing heat exchanger <NUM> where it cools and condenses flue gases exiting desorber <NUM>, then absorber <NUM> and condenser <NUM> (flow order of absorber <NUM> and condenser <NUM> may be reversed or heat transfer fluid <NUM> may be directed through absorber <NUM> and condenser <NUM> in parallel). In cooling mode (when vapor compression system is operating), heat transfer fluid <NUM> flows through evaporator <NUM>. Valve <NUM> directs the heat transfer fluid to the appropriate heat exchangers depending upon whether heating or cooling is desired.

<FIG> depicts a hydronic loop 914A and 914B of the <NUM>-pipe arrangement that connects the hybrid fossil fuel-electric multifunction heat pump to heat exchangers located inside the building for cooling and/or heating. Heat transfer fluid <NUM> flowing in hydronic loop 914A returns from inside the building to the hybrid heat pump and first flows through (if in heating mode when sorption system is operating) optional condensing heat exchanger <NUM> where it cools and condenses flue gases exiting desorber <NUM>, then absorber <NUM> and condenser <NUM> (flow order of absorber <NUM> and condenser <NUM> may be reversed or heat transfer fluid <NUM> may be directed through absorber <NUM> and condenser <NUM> in parallel). Optionally, if vapor compression system is operating and water heating is desired at the same time, heat transfer fluid <NUM> may be directed through de-superheater <NUM> through valve <NUM>. The de-superheater is a heat exchanger located in the vapor compression system, between the compressor <NUM> outlet and condenser <NUM> inlet. Heat transfer fluid <NUM> is heated in de-superheater <NUM>, while pre-cooling refrigerant vapor prior to entering condenser <NUM>.

In cooling mode (when vapor compression system is operating), heat transfer fluid <NUM> flows through evaporator <NUM>. For the <NUM>-pipe configuration shown in <FIG>, both the sorption system (heating) and vapor compression system (cooling) may operate at the same time, where heat transfer fluid <NUM> flows through both hydronic loops 914A and 914B at the same time.

<FIG> depicts a hydronic loop <NUM> of the <NUM>-pipe arrangement that connects the hybrid fossil fuel-electric multifunction heat pump to heat exchanger(s) located inside the building for heating, and a refrigerant loop <NUM> that connects the hybrid fossil fuel-electric multifunction heat pump to heat exchanger(s) located inside the building for cooling Heat transfer fluid <NUM> flowing in hydronic loop <NUM> returns from inside the building to the hybrid heat pump and first flows through (if in heating mode when sorption system is operating) optional condensing heat exchanger <NUM> where it cools and condenses flue gases exiting desorber <NUM>, then absorber <NUM> and condenser <NUM> (flow order of absorber <NUM> and condenser <NUM> may be reversed or heat transfer fluid <NUM> may be directed through absorber <NUM> and condenser <NUM> in parallel). Optionally, if vapor compression system is operating and water heating is desired at the same time, heat transfer fluid <NUM> may be directed through de-superheater <NUM> through valve <NUM>. The de-superheater is a heat exchanger located in the vapor compression system, between the compressor <NUM> outlet and condenser <NUM> inlet. Heat transfer fluid <NUM> is heated in de-superheater <NUM>, while pre-cooling refrigerant vapor prior to entering condenser <NUM>.

In cooling mode (when vapor compression system is operating), refrigerant <NUM> returns from evaporator <NUM> (not shown, located inside building) and flows through condenser <NUM>, de-superheater <NUM> and condenser <NUM>. For the hydronic-refrigerant configuration shown in <FIG>, both the sorption system (heating) and vapor compression system (cooling) may operate at the same time, where heat transfer fluid <NUM> flows through hydronic loops <NUM> and refrigerant <NUM> flows through refrigerant loop <NUM> at the same time.

<FIG> depicts the top view of the hybrid fossil fuel-electric multifunction heat pump <NUM> using hydronic loops 1114A and 1114B for heating and cooling (<NUM>-pipe configuration), nested evaporator <NUM> and condenser <NUM> heat exchangers, and all sorption and vapor compression system components inside a single enclosure <NUM>. Alternatively, <FIG> could show integrated heat exchanger <NUM> in place of the nested arrangement with equivalent function. Fan <NUM> forces ambient air <NUM> through the evaporator <NUM> and condenser <NUM> heat exchangers. Connected to the hybrid heat pump assembly is electric power <NUM> and control wires <NUM> which are routed to shared system controller <NUM>, fossil-fuel source <NUM>, and the two hydronic loops 1114A and 1114B. Heat transfer fluid <NUM> flows though hydronic loops 1114A and 1114B in the fashion described in <FIG>. Alternatively, <FIG> could show the <NUM>-pipe hydronic configuration described in <FIG>. For clarity, sorption system components are shown collectively as <NUM>.

Claim 1:
A heating and cooling system for a building (<NUM>) having a hybrid fossil fuel-electric multifunction heat pump (<NUM>, <NUM>, <NUM>) comprising:
a fuel-fired, thermally activated sorption heat pump system (<NUM>, <NUM>) for space and/or water heating comprising at least a desorber (<NUM>), a condenser of the sorption heat pump system (<NUM>, <NUM>, <NUM>, <NUM>), an evaporator of the sorption heat pump (<NUM>, <NUM>, <NUM>) and an absorber (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>),
an electric-powered vapor compression heat pump system comprising at least a compressor (<NUM>, <NUM>, <NUM>, <NUM>), a condenser of the vapor compression heat pump system (<NUM>, <NUM>, <NUM>, <NUM>) and an evaporator of the vapor compression heat pump system (<NUM>, <NUM>, <NUM>, <NUM>), and
an air-moving device (<NUM>, <NUM>, <NUM>, <NUM>) configured to cause ambient air to flow over both the evaporator (<NUM>, <NUM>) of the sorption heat pump system (<NUM>, <NUM>) and condenser (<NUM>, <NUM>, <NUM>, <NUM>) (<NUM>) of the vapor compression heat pump system, wherein the air-moving device (<NUM>, <NUM>, <NUM>, <NUM>) is configured to cause ambient air to flow through the evaporator (<NUM>, <NUM>) of the sorption heat pump system (<NUM>, <NUM>) (<NUM>) and then flow through the condenser (<NUM>, <NUM>, <NUM>, <NUM>) of the vapor compression heat pump system.