WO2014128089A1 - A combined heat and power system - Google Patents
A combined heat and power system Download PDFInfo
- Publication number
- WO2014128089A1 WO2014128089A1 PCT/EP2014/053045 EP2014053045W WO2014128089A1 WO 2014128089 A1 WO2014128089 A1 WO 2014128089A1 EP 2014053045 W EP2014053045 W EP 2014053045W WO 2014128089 A1 WO2014128089 A1 WO 2014128089A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- heat exchanger
- chamber
- combustion chamber
- stirling engine
- heat
- Prior art date
Links
- 238000002485 combustion reaction Methods 0.000 claims abstract description 32
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 25
- 239000004449 solid propellant Substances 0.000 claims abstract description 14
- 230000005611 electricity Effects 0.000 claims abstract description 6
- 239000000446 fuel Substances 0.000 claims abstract description 5
- 238000011144 upstream manufacturing Methods 0.000 claims description 3
- 239000007789 gas Substances 0.000 description 16
- 239000008188 pellet Substances 0.000 description 6
- 239000000567 combustion gas Substances 0.000 description 4
- 239000002028 Biomass Substances 0.000 description 3
- 239000000356 contaminant Substances 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 239000003245 coal Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 239000002803 fossil fuel Substances 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000010813 municipal solid waste Substances 0.000 description 1
- 239000003345 natural gas Substances 0.000 description 1
- 238000005192 partition Methods 0.000 description 1
- 239000003415 peat Substances 0.000 description 1
- 239000011343 solid material Substances 0.000 description 1
- 239000002918 waste heat Substances 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02G—HOT GAS OR COMBUSTION-PRODUCT POSITIVE-DISPLACEMENT ENGINE PLANTS; USE OF WASTE HEAT OF COMBUSTION ENGINES; NOT OTHERWISE PROVIDED FOR
- F02G1/00—Hot gas positive-displacement engine plants
- F02G1/04—Hot gas positive-displacement engine plants of closed-cycle type
- F02G1/043—Hot gas positive-displacement engine plants of closed-cycle type the engine being operated by expansion and contraction of a mass of working gas which is heated and cooled in one of a plurality of constantly communicating expansible chambers, e.g. Stirling cycle type engines
- F02G1/053—Component parts or details
- F02G1/055—Heaters or coolers
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
- F24H1/00—Water heaters, e.g. boilers, continuous-flow heaters or water-storage heaters
- F24H1/22—Water heaters other than continuous-flow or water-storage heaters, e.g. water heaters for central heating
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
- F24H1/00—Water heaters, e.g. boilers, continuous-flow heaters or water-storage heaters
- F24H1/46—Water heaters having plural combustion chambers
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
- F24H9/00—Details
- F24H9/0005—Details for water heaters
- F24H9/001—Guiding means
- F24H9/0026—Guiding means in combustion gas channels
- F24H9/0031—Guiding means in combustion gas channels with means for changing or adapting the path of the flue gas
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
- F24H9/00—Details
- F24H9/20—Arrangement or mounting of control or safety devices
- F24H9/2007—Arrangement or mounting of control or safety devices for water heaters
- F24H9/2057—Arrangement or mounting of control or safety devices for water heaters using solid fuel
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02G—HOT GAS OR COMBUSTION-PRODUCT POSITIVE-DISPLACEMENT ENGINE PLANTS; USE OF WASTE HEAT OF COMBUSTION ENGINES; NOT OTHERWISE PROVIDED FOR
- F02G2254/00—Heat inputs
- F02G2254/10—Heat inputs by burners
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24D—DOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR
- F24D18/00—Small-scale combined heat and power [CHP] generation systems specially adapted for domestic heating, space heating or domestic hot-water supply
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24D—DOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR
- F24D2101/00—Electric generators of small-scale CHP systems
- F24D2101/80—Electric generators driven by external combustion engines, e.g. Stirling engines
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24D—DOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR
- F24D2103/00—Thermal aspects of small-scale CHP systems
- F24D2103/10—Small-scale CHP systems characterised by their heat recovery units
- F24D2103/13—Small-scale CHP systems characterised by their heat recovery units characterised by their heat exchangers
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
- F24H2230/00—Solid fuel fired boiler
Definitions
- the present invention relates to a combined heat and power system.
- Stirling engines are well known to be particularly effective in combined heat and power systems, particularly for small to medium scale devices.
- a Stirling engine such as the MicrogenTM lkWe engine is a compact sealed unit which is able to generate electricity when its head is exposed to a heat source. The waste heat is usable to provide water or space heating.
- the Stirling engine is particularly versatile as it can be used with various heat sources. In a domestic
- the present invention relates to a combined heat and power system using a Stirling engine which is powered by a solid fuel.
- the solid fuel is preferably biomass such as wood chips, municipal solid waste or crop material, but may also be a fossil fuel such as coal or peat.
- known arrangement comprises a hopper into which pellets the solid fuel are deposited and a feed screw system to transfer small amounts of solid material to a combustion chamber where they are burned.
- a number of aspects of a solid fuel burner do not sit well with the requirements of a Stirling engine.
- the head of the Stirling engine is generally provided with an array of fins which serve to enhance the heat transfer to the head. If these are exposed to the tar and ash, they will foul the head and quickly reduce the operating
- a requirement of a Stirling engine is that it can quickly be shut off due to a loss of electrical power or an electricity grid fault condition.
- a solid fuel biomass burner does not lend itself to such a rapid change and, indeed, in many circumstances, it will be desirable to continue to operate the burner in order to generate heat. If the Stirling engine was exposed to this heat after it has been shut down, it will overheat.
- a combined heat and power system comprising a source of solid fuel
- a feed mechanism to supply the fuel to a combustion chamber ;
- a burner within the combustion chamber to combust the fuel the combustion chamber having first and second outlets for the hot exhaust gas; a first heat exchanger fed with hot exhaust gas from the first outlet, the first heat exchanger being connected to a water supply to provide a supply of hot water;
- a Stirling engine with a head, the head being in a second chamber to which the second outlet leads, the
- Stirling engine being arranged to generate electricity when exposed to the hot exhaust gas and having an electrical power outlet;
- the second heat exchanger downstream of the second chamber, the second heat exchanger being arranged to receive hot exhaust gas once it has passed the Stirling engine head, the second heat exchanger being connected to a water supply to provide a supply of hot water;
- a fan to draw air through the combustion chamber; and a damper to control the flow of gas through the second chamber and second heat exchanger.
- the flow of exhaust gas is separated into two flow paths, the first supplying heat to the first exchanger, and the second supplying heat to the Stirling engine head in the second chamber and the second heat exchanger.
- the damper allows the flow through the Stirling engine chamber and second heat exchanger to be controlled.
- the damper can substantially prevent any flow past the Stirling engine head.
- the damper can be opened to allow flow past the Stirling engine head.
- the damper is effectively able to vary the relative proportion of hot gases flowing to the first heat exchanger and the Stirling engine head/second heat exchanger. This provides the flexibility to run the system in a manner compatible with the heat and electrical output demand. Should the Stirling engine be required to shut down while the burner continues to operate either because its heat output is still required or because it cannot be shut down as quickly as the Stirling engine, the damper can close, thereby substantially preventing the flow of hot exhaust gases past the Stirling engine head.
- the damper on its own, has a reasonable degree of control of the system.
- a second fan is provided for the gas stream through the second chamber and the second heat exchanger. This provides a further degree of control as this allows the flow through the second chamber and the second heat exchanger to be actively boosted.
- the electrical output is proportionately
- the first and second heat exchangers may be fed by separate water supply sources. However, preferably, they are fed by a common water supply. In this case, the water is preferably supplied to the second heat exchanger upstream of the first heat exchanger, as the second heat exchanger will generally have a lower thermal output.
- the first and second heat exchangers are preferably in a common block. Preferably, also, the water supply is supplied to cool the Stirling engine upstream of the first and second heat exchangers.
- the first heat exchanger is positioned directly above the combustion chamber and the second outlet into the second chamber is in the lower portion of the combustion chamber. As well as the closed damper inhibiting the flow of contaminants towards the Stirling engine head, this arrangement also helps to prevent these from entering the second chamber.
- baffle extending across a substantial portion of the upper region of the combustion chamber. This ensures that the majority of tar and ash produced in the early stages of combustion will impinge on the baffle (s) and will not reach the first heat exchanger.
- the present invention requires a Stirling engine 1 and solid fuel burner 2, both of which are well known in the art and will not be described in detail here.
- the Stirling engine is preferably a linear free piston
- Stirling engine One such engine is the MicrogenTM lkWe engine. This is described, for example, in WO 02/14671 and WO 04/101982.
- the Stirling engine has a displacer and a power piston which reciprocate out of phase with one another when heat is applied to the head 3 of the engine.
- An alternator is positioned adjacent to the power piston to provide an AC output 4 as the power piston reciprocates with respect to a magnet.
- the solid fuel burner is also well known.
- a suitable burner is incorporated in automatic pellet boilers such as those from Froling, Okofen and Baxi Brotje.
- the solid fuel burner comprises a hopper 5 and a removable lid 6. This allows the hopper 5 to be manually filled with a regular supply of solid fuel pellets P.
- a feed screw 7 is provided beneath the hopper. This is controlled in accordance with the system requirements in order to deliver the desired amount of pellets to the burner 8.
- the burner 8 burns the pellets in the combustion chamber 9 and the ash left over following combustion drops into an ash pan 10 from which it is subsequently recovered by an operator .
- a second chamber 11 which contains the head 3 of the Stirling engine 1 is positioned immediately adjacent to the combustion chamber 9.
- a passage 12 connects the lower part of the combustion chamber 9 with the lower part of the second chamber 11.
- a fan 13 is provided adjacent to the combustion chamber 9 to feed air into the combustion chamber 9.
- a baffle 14 is provided immediately above the burner 8 to trap particulates in a combustion gas. Although shown as a simple plate, this baffle can take any configuration, for example, it may form a tortuous path for the combustion gases .
- a first heat exchanger 15 is provided directly above the combustion chamber 9 and is provided with a wound tube through which water is circulated.
- a second heat exchanger 16 which is also provided with a wound tube.
- a partition 17 separates the two heat exchangers.
- the water circuit for the heat exchangers comprises an inlet pump 18 which pumps water along a line 19 around a central part of the Stirling engine 1 in order to cool it and pre-heat the water before it enters the tubes of the second heat exchanger 16. It then subsequently flows through the tubes of the first heat exchanger 15 before exiting via a hot water outlet 20 where it can be used for space or hot water heating.
- a series arrangement of first and second heat exchangers is preferred, although these may be arranged in parallel or even have separate water
- the damper may be any suitable element which can selectively reduce the cross-sectional area of the duct 23 above the second heat exchanger 16, for example, a flap valve. However, it is preferably a butterfly valve which is rotatable about a horizontal axis as shown in Fig. 1.
- the second fan 22 is arranged to be operated to selectively increase the flow rate through the second heat exchanger 16 as desired. The exhaust gases are drawn out through the flue 24.
- pellets P are fed to the burner 8 by the feed screw 7 and are ignited.
- the combustion gases flow up through the first heat exchanger 15 with the majority of the particulates in the gas being trapped by the baffle 14.
- the position of the opening 12 and the back pressure caused by the damper 21 ensure that little, if any, of the combustion gases enter the Stirling head combustion chamber 11 at this time .
- the damper 21 can be moved to a more open position allowing combustion of gases to be drawn into the Stirling engine head chamber 11 and up through the second heat exchanger 16. In order to encourage this flow through the second heat exchanger 16, the fan 22 may be operated at this time.
- the burner 8 may continue to operate. In this case, the damper 21 is closed and the fan 22 switched off such that the flow reverts to being essentially via the first heat exchanger 15.
- the fan 13 could be replaced by an exhaust gas fan either immediately downstream of the first heat exchanger 15 or in the flue 24 such that it draws gas through both heat exchangers. In this latter case, there may be no need to have the additional fan 22 in the duct 23.
Abstract
A combined heat and power system comprising a source (5) of solid fuel (P). A burner (8) within the combustion chamber (9) combusts the fuel. The combustion chamber has first and second outlets for the hot exhaust gas. A first heat exchanger (15) is fed with hot exhaust gas from the first outlet. A Stirling engine (1) in a second chamber (11) to which the second outlet leads, the Stirling engine being arranged to generate electricity when its head (3) is exposed to the hot exhaust gas. A second heat exchanger (16) is downstream of the second chamber, the second heat exchanger being arranged to receive hot exhaust gas once it has passed the Stirling engine head. The first and second heat exchangers are connected to a water supply (20) to provide a supply of hot water. A fan (13, 22) draws air through the combustion chamber. A damper (21) controls the flow of gas through the second chamber and second heat exchanger.
Description
A COMBINED HEAT AND POWER SYSTEM
The present invention relates to a combined heat and power system.
In particular, it relates to a system which uses a Stirling engine as the prime mover. Stirling engines are well known to be particularly effective in combined heat and power systems, particularly for small to medium scale devices. A Stirling engine such as the Microgen™ lkWe engine is a compact sealed unit which is able to generate electricity when its head is exposed to a heat source. The waste heat is usable to provide water or space heating. The Stirling engine is particularly versatile as it can be used with various heat sources. In a domestic
environment, it can conveniently be powered by natural gas where the infrastructure exists to provide this. However, it can also be powered by alternative sources such as biomass or solar making it suitable for use in remote locations where no gas infrastructure is available.
The present invention relates to a combined heat and power system using a Stirling engine which is powered by a solid fuel. The solid fuel is preferably biomass such as wood chips, municipal solid waste or crop material, but may also be a fossil fuel such as coal or peat.
Such solid fuel burners are well known in the art.
known arrangement comprises a hopper into which pellets the solid fuel are deposited and a feed screw system to
transfer small amounts of solid material to a combustion chamber where they are burned.
A number of aspects of a solid fuel burner do not sit well with the requirements of a Stirling engine.
Particularly during the initial start-up of a solid fuel burner, the combustion process generates an amount of particulate contaminants in the form of tar and ash. The head of the Stirling engine is generally provided with an array of fins which serve to enhance the heat transfer to the head. If these are exposed to the tar and ash, they will foul the head and quickly reduce the operating
efficiency of the engine. Secondly, a requirement of a Stirling engine is that it can quickly be shut off due to a loss of electrical power or an electricity grid fault condition. On the other hand, a solid fuel biomass burner does not lend itself to such a rapid change and, indeed, in many circumstances, it will be desirable to continue to operate the burner in order to generate heat. If the Stirling engine was exposed to this heat after it has been shut down, it will overheat.
According to the present invention, there is provided: a combined heat and power system comprising a source of solid fuel;
a feed mechanism to supply the fuel to a combustion chamber ;
a burner within the combustion chamber to combust the fuel, the combustion chamber having first and second outlets for the hot exhaust gas;
a first heat exchanger fed with hot exhaust gas from the first outlet, the first heat exchanger being connected to a water supply to provide a supply of hot water;
a Stirling engine with a head, the head being in a second chamber to which the second outlet leads, the
Stirling engine being arranged to generate electricity when exposed to the hot exhaust gas and having an electrical power outlet;
a second heat exchanger downstream of the second chamber, the second heat exchanger being arranged to receive hot exhaust gas once it has passed the Stirling engine head, the second heat exchanger being connected to a water supply to provide a supply of hot water;
a fan to draw air through the combustion chamber; and a damper to control the flow of gas through the second chamber and second heat exchanger.
Thus, the flow of exhaust gas is separated into two flow paths, the first supplying heat to the first exchanger, and the second supplying heat to the Stirling engine head in the second chamber and the second heat exchanger. The damper allows the flow through the Stirling engine chamber and second heat exchanger to be controlled. Thus, during start-up when the combustion is particularly dirty, the damper can substantially prevent any flow past the Stirling engine head. Once combustion is fully established and the contaminants largely eliminated, the damper can be opened to allow flow past the Stirling engine head. In normal operation, the damper is effectively able to vary the relative proportion of hot gases flowing to the first heat exchanger and the Stirling engine head/second
heat exchanger. This provides the flexibility to run the system in a manner compatible with the heat and electrical output demand. Should the Stirling engine be required to shut down while the burner continues to operate either because its heat output is still required or because it cannot be shut down as quickly as the Stirling engine, the damper can close, thereby substantially preventing the flow of hot exhaust gases past the Stirling engine head.
As can be appreciated from the above, the damper, on its own, has a reasonable degree of control of the system. However, preferably, a second fan is provided for the gas stream through the second chamber and the second heat exchanger. This provides a further degree of control as this allows the flow through the second chamber and the second heat exchanger to be actively boosted. For example, in a mode in which the damper is fully open and the second fan is running, while the first fan is run at a relatively low speed, the electrical output is proportionately
increased, as is the proportion of the exhaust gas passing through the second exchanger in preference to the first. This mode of operation provides maximum electrical output with minimal thermal output. Alternatively, with the damper open, the second fan running and the first fan running at full speed, both the electrical and thermal output can be maximised . The first and second heat exchangers may be fed by separate water supply sources. However, preferably, they are fed by a common water supply. In this case, the water
is preferably supplied to the second heat exchanger upstream of the first heat exchanger, as the second heat exchanger will generally have a lower thermal output. The first and second heat exchangers are preferably in a common block. Preferably, also, the water supply is supplied to cool the Stirling engine upstream of the first and second heat exchangers. This not only provides the required cooling for the Stirling engine, but also serves to pre-heat the water. The system would work with the components in any suitable orientation. However, preferably, the first heat exchanger is positioned directly above the combustion chamber and the second outlet into the second chamber is in the lower portion of the combustion chamber. As well as the closed damper inhibiting the flow of contaminants towards the Stirling engine head, this arrangement also helps to prevent these from entering the second chamber.
As a further refinement, there is preferably at least one baffle extending across a substantial portion of the upper region of the combustion chamber. This ensures that the majority of tar and ash produced in the early stages of combustion will impinge on the baffle (s) and will not reach the first heat exchanger.
An example of a system constructed in accordance with the present invention will now be described with reference to the accompanying drawing which is a schematic view of the system.
The present invention requires a Stirling engine 1 and solid fuel burner 2, both of which are well known in the art and will not be described in detail here. The Stirling engine is preferably a linear free piston
Stirling engine. One such engine is the Microgen™ lkWe engine. This is described, for example, in WO 02/14671 and WO 04/101982. The Stirling engine has a displacer and a power piston which reciprocate out of phase with one another when heat is applied to the head 3 of the engine. An alternator is positioned adjacent to the power piston to provide an AC output 4 as the power piston reciprocates with respect to a magnet.
Similarly, the solid fuel burner is also well known. A suitable burner is incorporated in automatic pellet boilers such as those from Froling, Okofen and Baxi Brotje. In broad terms, the solid fuel burner comprises a hopper 5 and a removable lid 6. This allows the hopper 5 to be manually filled with a regular supply of solid fuel pellets P. A feed screw 7 is provided beneath the hopper. This is controlled in accordance with the system requirements in order to deliver the desired amount of pellets to the burner 8. The burner 8 burns the pellets in the combustion chamber 9 and the ash left over following combustion drops into an ash pan 10 from which it is subsequently recovered by an operator .
A second chamber 11 which contains the head 3 of the Stirling engine 1 is positioned immediately adjacent to the
combustion chamber 9. A passage 12 connects the lower part of the combustion chamber 9 with the lower part of the second chamber 11. A fan 13 is provided adjacent to the combustion chamber 9 to feed air into the combustion chamber 9. A baffle 14 is provided immediately above the burner 8 to trap particulates in a combustion gas. Although shown as a simple plate, this baffle can take any configuration, for example, it may form a tortuous path for the combustion gases .
A first heat exchanger 15 is provided directly above the combustion chamber 9 and is provided with a wound tube through which water is circulated. Similarly, above the second chamber 11 is a second heat exchanger 16 which is also provided with a wound tube. A partition 17 separates the two heat exchangers.
The water circuit for the heat exchangers comprises an inlet pump 18 which pumps water along a line 19 around a central part of the Stirling engine 1 in order to cool it and pre-heat the water before it enters the tubes of the second heat exchanger 16. It then subsequently flows through the tubes of the first heat exchanger 15 before exiting via a hot water outlet 20 where it can be used for space or hot water heating. A series arrangement of first and second heat exchangers is preferred, although these may be arranged in parallel or even have separate water
circuits . Above the second heat exchanger 16 is a damper 21 and a second fan 22. The damper may be any suitable element which can selectively reduce the cross-sectional area of the duct
23 above the second heat exchanger 16, for example, a flap valve. However, it is preferably a butterfly valve which is rotatable about a horizontal axis as shown in Fig. 1. The second fan 22 is arranged to be operated to selectively increase the flow rate through the second heat exchanger 16 as desired. The exhaust gases are drawn out through the flue 24.
On initial start-up of the burner 2, the damper 21 is horizontal thereby providing maximum obstruction in the duct 23 and the fan 22 is off. When the first fan 13 is
operating, pellets P are fed to the burner 8 by the feed screw 7 and are ignited. The combustion gases flow up through the first heat exchanger 15 with the majority of the particulates in the gas being trapped by the baffle 14. The position of the opening 12 and the back pressure caused by the damper 21 ensure that little, if any, of the combustion gases enter the Stirling head combustion chamber 11 at this time .
Once full clean combustion is established and
electrical output is required, the damper 21 can be moved to a more open position allowing combustion of gases to be drawn into the Stirling engine head chamber 11 and up through the second heat exchanger 16. In order to encourage this flow through the second heat exchanger 16, the fan 22 may be operated at this time.
In the event that the Stirling engine stops operating either because the demand for electricity drops, or because an emergency shutdown is required, the burner 8 may continue to operate. In this case, the damper 21 is closed and the
fan 22 switched off such that the flow reverts to being essentially via the first heat exchanger 15.
In an alternative arrangement, the fan 13 could be replaced by an exhaust gas fan either immediately downstream of the first heat exchanger 15 or in the flue 24 such that it draws gas through both heat exchangers. In this latter case, there may be no need to have the additional fan 22 in the duct 23.
Although described with reference to a single Stirling engine 1, a number of Stirling engines could be provided with their heads positioned in the Stirling second chamber 11 in order to boost the electrical output of the system.
Claims
1. A combined heat and power system comprising a source of solid fuel;
a feed mechanism to supply the fuel to a combustion chamber ;
a burner within the combustion chamber to combust the fuel, the combustion chamber having first and second outlets for the hot exhaust gas;
a first heat exchanger fed with hot exhaust gas from the first outlet, the first heat exchanger being connected to a water supply to provide a supply of hot water;
a Stirling engine with a head, the head being in a second chamber to which the second outlet leads, the
Stirling engine being arranged to generate electricity when exposed to the hot exhaust gas and having an electrical power outlet;
a second heat exchanger downstream of the second chamber, the second heat exchanger being arranged to receive hot exhaust gas once it has passed the Stirling engine head, the second heat exchanger being connected to a water supply to provide a supply of hot water;
a fan to draw air through the combustion chamber; and a damper to control the flow of gas through the second chamber and second heat exchanger.
2. A system according to claim 1, further comprising a second fan for the gas stream through the second chamber and the second heat exchanger.
3. A system according to claim 1 or claim 2, wherein the first and second heat exchangers are fed by a common water supply .
4. A system according to any one of the preceding claims, wherein the first and second heat exchangers are in a common block .
5. A system according to any one of claims 1 to 4, wherein the water supply is supplied to cool the Stirling engine upstream of the first and second heat exchangers.
6. A system according to any one of the preceding claims, wherein the first heat exchanger is positioned directly above the combustion chamber and the second outlet into the second chamber is in the lower portion of the combustion chamber .
7. A system according to any one of the preceding claims, further comprising at least one baffle extending across a substantial portion of the upper region of the combustion chamber .
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP14705152.8A EP2959234A1 (en) | 2013-02-21 | 2014-02-17 | A combined heat and power system |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GBGB1303080.4A GB201303080D0 (en) | 2013-02-21 | 2013-02-21 | A combined heat and power system |
GB1303080.4 | 2013-02-21 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2014128089A1 true WO2014128089A1 (en) | 2014-08-28 |
Family
ID=48091869
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/EP2014/053045 WO2014128089A1 (en) | 2013-02-21 | 2014-02-17 | A combined heat and power system |
Country Status (3)
Country | Link |
---|---|
EP (1) | EP2959234A1 (en) |
GB (1) | GB201303080D0 (en) |
WO (1) | WO2014128089A1 (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
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CN106871442A (en) * | 2017-03-17 | 2017-06-20 | 烟台尚美丽家新能源有限公司 | A kind of biomass fuel heating system |
IT201700046076A1 (en) * | 2017-04-28 | 2018-10-28 | T M A Di Bogliari S R L | Internal combustion stove, particularly of the perfected type. |
CN111609549A (en) * | 2020-05-15 | 2020-09-01 | 重庆燃气集团股份有限公司 | Hot water system for supplying stable electric power |
RU2791636C1 (en) * | 2022-01-19 | 2023-03-13 | Юлай Масабихович Насибуллин | Combustible rubbish engine |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5014680A (en) * | 1989-03-15 | 1991-05-14 | The United States Of America As Represented By The United States Department Of Energy | Self-powered automatic secondary air controllers for woodstoves and small furnaces |
WO2006135260A1 (en) * | 2005-06-13 | 2006-12-21 | Whisper Tech Limited | Cogeneration system with bypass exhaust passage |
US20070084942A1 (en) * | 2003-11-14 | 2007-04-19 | Hayashi Engineering Inc. | Domestic heat and power system |
DE102006001299A1 (en) * | 2006-01-11 | 2007-07-12 | Eckhart Weber | Wood pellet combined heat and power plant with Stirling engine in condensing technology |
WO2009098580A2 (en) * | 2008-02-06 | 2009-08-13 | Tradewave Ag | Cogeneration apparatus for heat and electric power production |
WO2011068419A1 (en) * | 2009-12-02 | 2011-06-09 | Whisper Tech Limited | Cogeneration system |
-
2013
- 2013-02-21 GB GBGB1303080.4A patent/GB201303080D0/en not_active Ceased
-
2014
- 2014-02-17 EP EP14705152.8A patent/EP2959234A1/en not_active Withdrawn
- 2014-02-17 WO PCT/EP2014/053045 patent/WO2014128089A1/en active Application Filing
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5014680A (en) * | 1989-03-15 | 1991-05-14 | The United States Of America As Represented By The United States Department Of Energy | Self-powered automatic secondary air controllers for woodstoves and small furnaces |
US20070084942A1 (en) * | 2003-11-14 | 2007-04-19 | Hayashi Engineering Inc. | Domestic heat and power system |
WO2006135260A1 (en) * | 2005-06-13 | 2006-12-21 | Whisper Tech Limited | Cogeneration system with bypass exhaust passage |
DE102006001299A1 (en) * | 2006-01-11 | 2007-07-12 | Eckhart Weber | Wood pellet combined heat and power plant with Stirling engine in condensing technology |
WO2009098580A2 (en) * | 2008-02-06 | 2009-08-13 | Tradewave Ag | Cogeneration apparatus for heat and electric power production |
WO2011068419A1 (en) * | 2009-12-02 | 2011-06-09 | Whisper Tech Limited | Cogeneration system |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN106871442A (en) * | 2017-03-17 | 2017-06-20 | 烟台尚美丽家新能源有限公司 | A kind of biomass fuel heating system |
IT201700046076A1 (en) * | 2017-04-28 | 2018-10-28 | T M A Di Bogliari S R L | Internal combustion stove, particularly of the perfected type. |
EP3399252A1 (en) * | 2017-04-28 | 2018-11-07 | T.M.A. DI BOGLIARI S.r.l. | An international combustion stove, in particular of an improved type |
RU2732095C2 (en) * | 2017-04-28 | 2020-09-11 | Т.М.А. ДИ БОЛЬЯРИ С.р.л. | Internal combustion furnace, in particular of an improved type |
CN111609549A (en) * | 2020-05-15 | 2020-09-01 | 重庆燃气集团股份有限公司 | Hot water system for supplying stable electric power |
RU2791636C1 (en) * | 2022-01-19 | 2023-03-13 | Юлай Масабихович Насибуллин | Combustible rubbish engine |
Also Published As
Publication number | Publication date |
---|---|
GB201303080D0 (en) | 2013-04-10 |
EP2959234A1 (en) | 2015-12-30 |
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