DE19740398A1 - Combined heat and power facility for energy supply - Google Patents

Abstract

The invention relates to a coupled power-heat device for heating, cooling and supplying buildings and installations with electric energy comprising an internal combustion engine (1), a generator (2) and a heat accumulator (4) to which a cooling accumulator (6) is assigned. Both accumulators (4, 6) are connected to one another via a heat pump (3), whereby the cooling accumulator (6) serves as a heat source for said heat pump (3). System modules which generate the heat energy having a relatively high thermal level are attached to the heat accumulator (4) and the modules which deliver the heat energy having a relatively low thermal level to the cooling accumulator (6).

Description

The invention relates to a combined heat and power Establishment of small to medium power to the Ener energy supply for private and / or public Buildings and facilities using primary energy from liquid or gaseous fuels, preferably natural gas.

There are already numerous from the state of the art Plants and facilities for the energy supply of Buildings with heat and electrical energy and for cleaning known for hot domestic water. The for the Heating, including hot water preparation, Kli automation and power generation of buildings Most plants are separated from one another installed and operated. That inevitably has Consequence that both the investment and the Operating costs, especially for those to be used Primary energies are high.  

DE 42 03 491 A1 describes an electronically controlled one Power supply unit known for generating of heat and electrical energy. The energy supply unit includes a generator for the Electricity generation from an internal combustion engine is driven. The thermal energy is generated from the Exhausting the engine and the cooling water from the burner engine obtained by means of heat exchanger and in provided a boiler. With the help of a heat pump pe, which is driven by the internal combustion engine, residual heat is recovered from the engine exhaust and used for heating the boiler. The Boiler may also be generated by the electrical energy can be heated. The energy ver care unit according to DE 42 03 491 A1 has none Equipment for air conditioning of buildings and Heat recovery from the exhaust air. Regenerative Energies are not used.

A similar heating and power plant for Conversion of primary energy and ambient heat into DE-OS 40 06 742 A1 proposes electrical energy and useful heat in front. The centerpiece of the system is a with a burner operated boiler and one with the same burner heated Stirling engine, one Generator and a heat pump drives. The generator is preferably a linear generator, which has a appropriate control with the drive motor one Heat pump, with the public power grid or with other consumers can be electrically connected can. With the help of the heat pump, heat is also increased recovered from the ambient heat and for Heating purposes provided. A subsystem for Air conditioning of buildings and facilities and Recovery of thermal energy from the air conditioning systems does not provide for this solution proposal.  

A combined system for the production of electrical devices gie using the waste heat from the Hausstromer Generation for space heating is from DE 44 34 831 A1 known. The electrical energy is with a gas mo Tor generator arrangement generated, with a Waste heat recovery pipeline as a heat source working heat exchanger to the gas engine genera gate arrangement is connected. In the source side a heat transfer medium is heated and the steam thus formed transfers the heat exchangers to the room heating supplied. The liquefied steam flows in closing after releasing its thermal energy into the source-side heat exchanger of the gas engine genera gate arrangement back. According to a preferred embodiment This system is also an absorption cooler direction provided in a circulation pipe is involved. The circulation pipeline is with a Gas-liquid phase changes in heat medium filled. There is heat at this circulation pipe exchanger connected to cool buildings serve undocking. The disadvantage of this facility again is that the facility has no funds for the use of renewable energies.

From DE 41 02 636 A1 it is also known that in a Combined heat and power plant with the help of a genera tors generated electrical energy in a battery to buffer. In addition to greater independence from public energy supply networks are supposed to this measure reduces the operating times of the system adorns and the in-house supply of electrical Energy better adapted to the respective needs can be. The proposed facility, the same in time for the supply of hot domestic water and with Heating is used, works exclusively with electrical energy as primary energy use and has none further equipment for the use of renewable energy  gien and for heat storage. Particularly disadvantageous it can be seen that larger amounts of heat in Spit stress times occur, not exploited and must be released to protect the system.

A proposal to incorporate solar panels in a heating system that uses fossil primary energy is operated is known from DE 26 91 774. The proposed heating system is also with a Liquid heat storage and equipped with heat pumps steadily in order to achieve the highest possible efficient use the heat generated by solar and primary energy to reach. The generated by the solar panels Thermal energy is used as much as possible in this plant used only for heating purposes. A further groove of solar energy, for example in the season in which the sunlight is not as strong and the use of further renewable energies does not provide this facility.

The invention has for its object an elek tronically controllable device of the beginning genus for heating, cooling and energy supply including buildings and facilities to develop renewable energies with relatively low cost and investment costs rea and the necessary share of primary energy for the heat and energy supply further redu graces.

According to the invention, the task is characterized by the claim 1 specified features solved. Beneficial Further developments of the invention result from the Claims 2 to 8.  

Known per se with the coupling according to the invention Basic modules and their specially coordinated combination a completely new quality in Utilization of the primary energy used has been achieved, the system according to the invention at the same time Heating, for producing hot domestic water and for Air conditioning (cooling) of buildings used can be. The invention therefore does not constitute a supplement expansion or expansion of known combined heat and power systems, but a new type, perfect standalone and environmentally friendly solution that is extremely economical. In its entirety, it unites the complex functions Heating, electricity generation, hot water generation supply and cooling with efficient use of regenerati ver environmental energies.

The system according to the invention for the winter Generation of heat and electrical energy from fossil Energy sources, such as gas or oil, is used for climatization in summer of buildings and facilities and for maintenance warm hot water at the same time Power generation. So there are no additional ones Air conditioning costs necessary in summer dig, which only corresponds to the project planning appropriate dimensions of the heating surfaces visible during the summer operation as Serve cooling surfaces.

The system according to the invention can effizi anywhere there ent used and thus the primary energy consumption be reduced where currently conventional Gas, oil or solid fuel heaters are installed.  

The centerpiece of the combined heat and power plant A hot storage tank is connected to the device with an additional cold storage, which accordingly the invention with an internal combustion engine, the one Power generator drives, and with a heat pump, either as compression or absorption heat pump is designed, and solar devices for Utilization of renewable energies as well as that of Use of the primary heat generated waste heat that is.

By using the two memories, ent speaking dimensioning of the overall system the Be number of hours of the engine designed so be that with proper maintenance a top possible service life without problems with standard machines is achieved. The use of special and therefore expensive internal combustion engines that are for permanent use drive must be designed, are therefore not required. By integrating the heat pumps location it is even possible for this application an inexpensive air-cooled fuel machine use because the cylinder and housing waste heat usable into the storage system can. The system according to the invention temperature and dew point control is secured by the application of a efficient, electronic control exploitation of renewable energies. The run time of combined heat and power facilities and the consumption of primary energies can result from the Energy storage is reduced to a minimum the.  

The one in the internal combustion engine that is coupled with a generator for generating electrical energy is used and serves to drive the heat pump, The heat generated is burned via the cooling system engine at different thermal levels Warm or cold storage supplied. With the help of Wär is transferred to the exhaust gases, the cooling water and the engine oil of the internal combustion engine on thermal part of the residual heat was removed at a relatively high level and turned on for further charging of the heat accumulator couples.

With the help of a condensing condenser, the be already cooled exhaust gases further residual heat finally the heat of condensation due to the Calorific value effect removed and the cold storage fed relatively low thermal level.

According to an essential feature of the invention Internal combustion engine generator unit in a sound and thermally insulated housing thermally encapsulated. The waste heat generated in the housing is removed by an air-water heat exchanger at thermally low Coupled into the cold store according to the level and can thereby also be used. These energies serve as a source for the heat pump.

The invention is almost complete Use of the waste heat from the system ensures what the Combined heat and power plant (CHP) principle, including the Use of the condensing effect corresponds.

Via the cold storage to which a recooler is connected Heat recovery from a ventilation system Building, a heat exchanger for the exploitation of the Waste water residual heat and during winter operation the solar collectors are also connected on the primary side  are with the heat pump that the hot water tank thermally connected to the cold storage, heat energies from the environment that are relatively low Own, exploited and with a higher level thermal level in the hot storage tank for preparation hot water for heating and for warm Process water fed. Due to the system the use of the heat pump the effectiveness of the inventions cogeneration device according to the invention increased in that a more usable heat and Electrical energy is provided as the one set primary energy includes.

This effect results from the coupling of the Interaction of environmental energy from the solar system with the heat pump.

The invention is intended to be an embodiment example will be explained in more detail. The Associated Drawing shows a schematic representation of the Cogeneration heating, cooling and Power supply facility.

As can be seen from the drawing, the primary energy used for heating, for air conditioning (cooling), for generating electrical energy and for hot domestic water, in the present exemplary embodiment preferably natural gas, in a manner known per se of an internal combustion engine 1 , for example a gas engine or Turbine fed, which drives a generator 2 for generating electrical energy. Internal combustion engine 1 and generator 2 are housed in a sound and heat insulated housing 36 , which with a supply for supply and exhaust air 37 ; 38 is equipped for cooling purposes.

To the generator 2 , which drives the heat pump 3 , the house network 34 for the electrical power supply and the public e-network are connected via the e-network connection 32 . The connection to the public E-network is made with the interposition of meter units 15 for the purchase and for the recovery / supply of electrical energy.

The generator 2 is preferably designed as Asynchronmaschi ne, which is rigidly connected to the internal combustion engine 1 . This variant offers the advantage that the generator is used as a drive to start the internal combustion engine 1 and at the same time there is no need for complex network synchronizations. A so-called soft start circuit may be necessary for generators with high power. The use of synchronous or direct current generators is of course possible and makes sense, among other things, if an island operating mode of the electrical energy supply system is desired.

After the starting process, the internal combustion engine 1 runs up at the nominal speed of the motor in accordance with the mains frequency present. When the internal combustion engine is loaded by increasing the primary energy supply, the generator 2 is over-synchronized, and current is fed into the connected network. The load on the internal combustion engine can be controlled by measuring the power so that the generator works with its specified nominal power. This condition forms the nominal operating point for the generation of electrical energy and waste heat.

If 34 electrical energy is consumed in the house network connected in parallel during generator operation, the energy is supplied directly by generator 2 and does not have to be taken from the public electrical network for a fee. By using the hot storage 4 , the running time of the device for generating electrical energy can be controlled so that it always works when the electrical energy consumption in the building or in the public network is given.

In principle, instead of the engine genes rator unit also the use of a fuel cell possible without the downstream systems parts and active principles thereby change significantly other.

Due to the intermittent operation of the system according to the invention, it is useful and economical to temporarily store the electrical energy generated. According to the present embodiment, the alternating current generated by the generator 2 is rectified in a photovoltaic system 16 and supplied to a battery system integrated into the system 16 , in which the electrical energy is stored. The electrical energy stored in this way for self-consumption is fed into the house network 34 by the inverter as AC voltage via the E-grid connection 33 and the switching device 40 . In addition, the photovoltaic system 16 is connected to the public electric network.

The solar panels included in the photovoltaic system 16 supplement the use with regenerative energy in a known manner.

In addition to the known use of a Warmspei chers 4 , an additional cold storage 6 is part of the combined heat and power device according to the invention. This cold storage 6 serves on the one hand as a heat supplier for the evaporator of the heat pump 3 in the heating mode during winter operation and as a cold supplier in the cooling mode in the air conditioning of the buildings in summer operation.

During winter operation, the solar collectors 13 , the condensing condenser 42 and the cooling system 10 of the internal combustion engine 1 and generator 2 are connected to the cold store 6 , which is connected to the hot store 4 via the heat pump 3, on the primary side by means of the lines 5 .

A heat exchanger for utilizing the waste heat from the exhaust air recooling 27 of the building is also connected to the cold store 6 . All vorgenann th modules deliver thermal energy with a relatively lower thermal level to the cold storage 6 , which forms the thermal energy source for the heat pump 3 .

In addition, a heat exchanger in the cold storage 6 with a waste water waste heat recovery 20 , which naturally has a waste water connection 19 and an overflow 31 to the sewer system, and via the valve 11 for the selectable changeover to summer and winter operation with the underfloor heating 28 and the heating / Heatsinks 29 connected to the building. Advantageously, the cold storage 6 is also equipped with a connection 7 for an additional cooling circuit.

To the hot storage 4 , which is preferably designed as a stratified storage, the exhaust system of the internal combustion engine 1 and in summer operation the solar collectors 13 are ruled out for charging it with thermal energy through the connecting lines 8 . Through the connecting lines 45 , the oil cooler of the internal combustion engine 1 is connected to the connecting lines 8 and thus directly coupled to the hot storage 4 . The condenser of the heat pump 3 serves as a further heat source for the warm store 4 .

An alternative heat generating device in the form of a conventional gas burner 39 (redundancy) complements the system according to the invention.

On the secondary side of the hot storage 4 via a mixer 18, the flow 21 of the heating installations, which at the same time for cooling or cooling during summer operation. Serve air conditioning, and the lines for the hot water connection 25 connected.

The flow 21 of the heating installations is connected to the cold storage 6 on the secondary side during the summer operation for air conditioning the rooms, to which the recooling 27 for heat recovery from the exhaust air of the building is connected in winter operation. The changeover to summer and winter operation is carried out with the help of the changeover valves 11 ; 12 and the valves 41 ; 42 and 43 realized, which are all controlled with the help of the electronic control unit 9 .

For the eventual accident at the Brennkraftmaschi ne 1 has as an alternative heat generating means in the exhaust passage of the internal combustion engine 1, the operational one exhaust stream switch 35 to summer and winter, a gas burner 39 is provided, which directly contact with exhaust gas heat exchanger 24 for charging the hot memory 4 via the connecting lines 8 is connected to this.

Via the secondary side to the hot water storage tank 4 , the mixer 18 is connected in a special way, the outside temperature-controlled regulation of the Heizungsvor run 21st Contrary to the general method, the mixer 18 is operated not only with three, but with several connection points. These are the hot water connection on the input side from the upper area of the hot storage 4 , the hot water connection from the central area of the hot storage 4 and the return 14 of the heating system and on the output side the flow 21 of the heating system. With the help of the electronic control unit 9 , the automatic switchover between the input lines for regulating the flow temperature takes place. So at Vorlauftem temperatures up to the average temperature of the hot storage 4 of the heating / cooling flow 21 in the middle memory area in conjunction with the cooler return 14 is operated. If the setpoint of the outside temperature-controlled control is above the temperature in the storage medium region, the admixture from the return 14 is interrupted. The admixture then takes place from the upper area of the hot storage 4 with hot water. This special arrangement of the input streams for the mixer 18 minimizes the consumption of hot water and thus greatly reduces the system start-ups for recharging the hot storage tank 4 . This effect directly benefits the life of the internal combustion engine 1 .

The return flow 14 of the heating equipment is the hot memory 4 is supplied to unterster point and supports in this way the thermal stratification in storage. 4 In order to achieve the lowest possible return temperatures, according to the invention in the heating / cooling return 14 of the building, for example, a floor or panel heating 28 and a preheater 26 for heating the inflowing fresh air of the ventilation system are arranged.

Within the hot storage tank 4 , heat exchangers are provided, by which the hot service water in the lower part of the hot storage tank 4 , which, as described above, is preferably designed as a stratified storage tank, is preheated. This on the one hand supports the desired cooling of the hot storage 4 in this storage area and at the same time minimizes the heat removal in the upper, hot storage area. A downstream simple thermal mixer 30 is used to set the desired end temperature of the treated hot water.

A major advantage of the combined heat and power device according to the invention is that the proposed system can be used effectively for heating purposes and during the summer operation for air conditioning / cooling of the buildings and facilities without additional equipment or plant-side changes in the cold seasons. In summer operation, the medium (water) in the cold storage 6 is cooled down to approximately 0 ° C. with the help of the heat pump 3 . This cold water is via switch valves 11 ; 12 fed to the mixer 18 for cooling operation in summer and for heating operation in winter and mixed to a temperature a little above the dew point of the air in the rooms to be cooled and via the cooling / heating surfaces 29 and possibly the floor heating 28 to the corresponding rooms led to cooling. It is done by the existing Heizan location, the cooling of the rooms without additional plant-side expenses are required. Existing ventilation and air conditioning systems are integrated into this cycle accordingly.

Another advantage is that when an absorption machine is used as the heat pump 3, the heat energy transported in the summer by the solar collectors 13 into the warm store 4 can be used for cooling. The energy source of the absorption chiller is then the charged Warmspei cher 4th

The solar collectors 13 integrated in the device according to the invention fulfill two tasks. Due to the direct connection of the solar collectors 13 with the hot storage 4 , the solar energy in the summer operation is used directly for the preparation of hot domestic water and, if necessary, for the preparation of warm water for heating purposes. This arrangement corresponds to the well-known classic application of solar systems in a temperature range above 50 ° C.

Especially in the colder season, however, the solar energy is generally no longer sufficient to heat the heat transfer medium of the solar collectors 13 to the desired temperature level of over 50 ° C. In conventional systems, the collectors are only partially used in the winter period.

In the device according to the invention, with the help of the heat pump 3 in conjunction with the cold store 6 collector flow temperatures of the solar collectors 13 of substantially less than 50 ° C. can be used efficiently all year round by the relatively low temperature level of the solar collectors 13 in the colder time of the year, the colder heat transfer medium is supplied in cold storage 6 via a heat exchanger. As a result, heat is transported from the environment into the cold store 6 at a relatively low temperature level. With the help of the heat pump 3 , this thermal energy is raised to a usable thermal level of about 50 ° C and the hot storage 4 , as already described ben, supplied. As a result, it is largely possible to dispense with other environmental heat suppliers for the operation of the heat pump 3 , as is the case, for example, with conventional heat pump systems for utilizing thermal energy from geothermal, water or air heat with a correspondingly high level of equipment and thus financial outlay. The Einrich device according to the invention differs fundamentally from known systems and systems and at the same time minimizes the plant-side effort by a consistent continuous use of the solar panels 13 takes place both in summer and in winter. The changeover to summer and winter operation is in turn carried out with the aid of the changeover valves 22 ; 23 made.

Reference list

1

Internal combustion engine

2nd

generator

3rd

Heat pump

4th

Hot storage

5

management

6

Cold storage

7

Connection for additional cooling circuit

8th

Connecting cable

9

electronic control unit

10th

cooler

11

Diverter valve

12th

Diverter valve

13

Solar collector

14

Rewind

15

Counter unit

16

Photovoltaic system

17th

-

18th

mixer

19th

Sewer pipe

20th

Wastewater buffer

21

Heating / cooling flow

22

Diverter valve

23

Diverter valve

24th

Exhaust gas heat exchanger

25th

Process water connection

26

Supply air preheating

27

Exhaust air recooling

28

Underfloor heating

29

Heating / cooling surfaces

30th

Domestic hot water thermostat

31

Wastewater overflow

32

E-mains connection

33

E-mains connection

34

House connection

35

Exhaust gas flow switch

36

Enclosure

37

Supply air

38

Exhaust air

39

Gas burner

40

Switching device

41

Valve

42

Condensing condenser

43

Valve

44

Valve

45

Connecting cable

Claims (10)

1. Combined heat and power device for heating, cooling and energy supply of buildings and facilities using fossil primary energy and using solar energy consisting of an internal combustion engine and a generator driven by it, which serves to operate a heat pump and with the house network Building and the public supply network for feeding electrical energy is connected and a heat exchanger arranged in the exhaust gas duct of the internal combustion engine, which is primarily connected to a heat accumulator together with a solar collector, to which the building equipment to be supplied with heat energy and hot water is connected on the secondary side. characterized in that the hot store (4), a cold storage (6) is associated with both memory (4; 6) are coupled via a heat pump (3) thermally with each other, system modules, the Wärmee nergie having a relatively high thermal Niv generate eau, to the hot storage tank ( 4 ) and system modules that supply thermal energy with a lower rigorous thermal level to the cold storage tank ( 6 ), which serves as a heat source for the heat pump ( 3 ), are connected. 2. Device according to claim 1, characterized in that the exhaust system of the internal combustion engine ( 1 ), the cooling system ( 10 ) of the internal combustion engine ( 1 ) and generator ( 2 ) and in summer the Sollar collectors ( 13 ), on the primary side to the Warm storage ( 4 ) and system modules ( 20 ; 27 ; 42 ) for the recovery and recovery of thermal energy from the building exhaust air, the waste water and during winter operation from the Sollar collectors ( 13 ) and the cooling system ( 10 ) of the internal combustion engine ( 1 ) and the generator ( 2 ) are connected on the primary side to the cold store ( 6 ). 3. Device according to claim 1 and 2, characterized in that the hot storage ( 4 ) and the cold storage ( 6 ) are stratified storage. 4. Device according to claim 1 and 2, characterized in that in the exhaust line of the internal combustion engine ( 1 ) as an alternative heat generation supply device, a gas burner ( 39 ), which is directly coupled to the hot storage tank ( 4 ) on the primary side, and an exhaust gas flow switch ( 35 ) are intended for summer and winter operation. 5. Device according to claim 1 and 2, characterized in that the waste water line (19) connected to the building at a sewage temporary storage (20) and the memory (20) is connected to a heat exchanger in the cold storage (6). 6. Device according to claim 1 and 2, characterized in that a supply air preheater ( 26 ) for conditioning the supply air of the ventilation system ge of the building in the return ( 14 ) of the heating / cooling installations ( 29 ; 28 ) is coupled. 7. Device according to claim 1 and 2, characterized in that an exhaust air recooling ( 27 ) is integrated in the ventilation system of the building and is thermally coupled to the cold store ( 6 ). 8. Device according to claim 1, 2 and 7, characterized in that in the heating / cooling flow ( 21 ), a mixer ( 18 ) is switched on and the mixer ( 18 ) on the input side of the warm store ( 4 ), each with a connection in the upper and middle area of the hot storage tank ( 4 ), the return ( 14 ) of the heating / cooling installations ( 28 ; 29 ) and the exhaust air recooling ( 27 ) of the building are connected. 9. Device according to one of claims 1 to 8, characterized in that the changeover to summer or winter operation by Umschaltventi le ( 11 ; 12 ; 22 ; 23 ), the connections in the line connections of the respective system modules for hot or cold storage ( 4th ; 6 ) are provided and the exhaust gas flow switchover ( 35 ) takes place and the valves ( 11 ; 12 ; 22 ; 23 ) and the switchover ( 35 ) can be controlled via the electronic control unit ( 9 ). 10. Device according to one of claims 1 to 8, characterized in that the changeover to the heating or cooling mode is carried out by the switching valves ( 11 ; 12 ;) and valves ( 41 ; 43 ; 44 ) which are operated via the mixer ( 18 ) in the heating and cooling flow ( 21 ) are switched on, the valves ( 41 ; 43 ) and the changeover valve ( 12 ) with the hot storage tank ( 4 ), the valve ( 44 ) with the return ( 14 ) and the exhaust air recooling ( 27 ) and the changeover valve ( 11 ) with the cold storage ( 6 ) and the exhaust air recooling ( 27 ) are connected.