Date of delivery: Contract No.: IEE/08/776/SI

Transcription

1 D4.2. /D 2.4. Concept for evaluation of Version 2.2 A defined methodology for calculation of the seasonal performance factor and a definition which devices of the system have to be included in this calculation. Heat s with hydronic ing systems Date of delivery: Contract No.: I/08/776/SI Authors: Andreas Zottl, AIT Roger Nordman, SP Co-Authors Michel Coevoet, df Philippe Riviere, Armines Marek Miara, IS Frauenhofer Anastasia Benou, CRS Peter Riederer, CSTB The sole responsibility for the content of this document lies with the authors. It does not necessarily reflect the opinion of the uropean Communities. The uropean Commission is not responsible for any use that may be made of the information contained therein. page 1 of 18 Version 2.0

2 Content FORWORD... 3 NOMNCLATUR... 3 SASONAL PRFORMANC FACTOR () VALUATION... 4 SYSTM BOUNDARY DSCRIPTION... 4 SYSTM BOUNDARIS HATING MOD: calculation ing mode:... 6 SYSTM BOUNDARIS COOLING MOD:... 8 calculation cooling mode:... 9 calculation simultaneous cooling and ing mode: OPRATING MODS SPAC HATING DOMOSTIC HOT WATR COOLING DFROST MOD Direct electric defrosting Hot gas defrosting Reverse cycle defrosting COMPARISON OF TH SYSTM- BOUNDARIS IN STANDARDS AND TH SYSTM BOUNDARIS OF TH -CALCULATION MTHODOLOGY LITRATUR ANNX CALCULATION XAMPL XAMPL-A HAT PUMP WITH LCTRIC BACK UP XAMPL-B HAT PUMP WITH ADDITIONAL GAS HATING page 2 of 18 Version 2.0

3 D4.2. Concept for evaluation of Foreword The aim of this document is to define the system boundaries for calculating the for ing and cooling of systems. Defining the system boundaries has direct impact on the necessary measurement equipment to measure the needed parameters for the calculation of the different. For this reason the document should be revised after the first measurement period to see if the defined system boundaries can be measured in the field or if there have to be some adoptions. Nomenclature SH space ing [-] DHW domestic hot water [-] HP [-] CU Cooling unit [-] i Seasonal performance factor (Index: H for ing, C for cooling) [-] COP Coefficient of performance [-] R nergy efficiency ratio [-] SR Seasonal energy efficiency ratio [-] For ing mode: H_hp quantity of of the HP in SH operation [kwh] W_hp quantity of of the HP in DHW operation [kwh] HW_bu quantity of of the back-up er for SH and DHW [kwh] S_fan/ electrical energy use of the HP source: fan or brine/well for [kwh] SH and DHW B_fan/ electrical energy use of the sink (building): fans or s for [kwh] SH and DHW bt_ electrical energy use of the buffer tank [kwh] HW_hp electrical energy use of the HP for SH and DHW [kwh] HW_bu energy use * of the back-up er for SH and DHW [kwh] * for additional ing other then electrical back up er the energy content of the fuel demand has to be taken For cooling mode: C produced cooling energy of the CU for cooling [kwh] S_fan/ electrical energy use of the CU- sink: fan or brine/well [kwh] B_fan/ electrical energy use of the building fans or s [kwh] CU electrical energy use of the CU [kwh] bt_ electrical energy use of the buffer tank [kwh] page 3 of 18 Version 2.0

4 D4.2. Concept for evaluation of Seasonal Performance Factor () evaluation D4.2.- Concept for evaluation of describes a standard evaluation method for monitoring results to get data for quality characteristics for systems and technologies. This calculation method also provides the possibility to include the impact of auxiliary devices like brine s and fans on the performance of the system, which will be taken into account by the definition of different system boundaries. The methodology of calculating the makes it possible to compare the system with common ing systems like oil or gas. By this comparison it is also possible to calculate the CO 2 - and primary energy reduction potential from different systems compared to other ing systems. This evaluation method is based on a harmonised monitoring methodology, also developed in the SPMO project, which allows disposing all necessary measurement data for applying the evaluation method presented in this document. System boundary description The definition of the system boundaries influences the results of the depending on the impact of the auxiliary drives. Therefore the should be calculated according to different system boundaries. This will reflect the impact of the different devices on the performance of the system. Due to the fact that the units can operate in ing and/or cooling mode the system boundaries and the -calculation methodology is separated for ing and cooling mode. According the described system boundaries the can be calculated for cooling, space ing and domestic hot water production. For systems with an additional ing system other than an electrical back up er (e.g. oil, gas or biomass) the quantity of and the energy content of the fuel demand have to be determined for calculating H3 and H4. The energy content can be determined by measuring the fuel demand and multiplying with the calorific value of the fuel. For additional solar thermal systems the electric auxiliary energy to run the system has to be measured. With the energy delivered to the ing system by the additional ing the energy supply ratio of the system is calculated. The following definitions of the system boundaries are a general description for all different ing and cooling systems considered in the project SPMO. Therefore the possibility to realise the measurement can be slightly different for the different systems, but it is possible to have correct comparisons within the different systems e.g. Air/Water with another Air/Water system. For technical reasons Air/Air systems can only be measured and analysed according to H3 / H4 and C3. page 4 of 18 Version 2.0

5 D4.2. Concept for evaluation of System boundaries ing mode: H1 : This system contains only the unit. H1 evaluate the performance of the refrigeration cycle. The system boundaries are similar to COP defined in N [1], except that the standard takes, in addition, a small part of the consumption to overcome head losses, and most part of fan consumption. H2 : This system contains of the unit and the equipment to make the source energy available for the. H2 evaluate the performance of the HP operation, and this level of system boundary responds to SCOP NT in prn [2] and the RS-Directive [3] requirements 1. Note: COP in N and SCOP NT in prn are more or less between H1 and H2 (see table 1 at the end of the document) H3 : This system contains of the unit, the equipment to make the source energy available and the back up er. H3 represents the system and thereby it can be used for comparison to conventional ing systems (e.g. oil, gas, ). This system boundary is similar to the in VDI [4], N [5] and the SCOP ON in prn For monovalent 2 systems H3 and H2 are identical. H4 : This system contains of the unit, the equipment to make the source energy available, the back up er and all auxiliary drives including the auxiliary of the sink system. H4 represents the ing system including all auxiliary drives which are installed in the ing system. H4 H3 H2 hot water tank space ig buffer tank H1 Figure 1: xample scheme for a ing system 1 For compact s having built-in electric backup ers, this would constitute a problem, since the is normally attributed the product, and then H3 is easier to evaluate in praqctice.. 2 Monovalent s are s without supplemental (backup) ing. page 5 of 18 Version 2.0

6 D4.2. Concept for evaluation of -calculation ing mode: In this chapter the formulas for calculating the for ing mode together with the energy flowcharts for the different system boundaries are described. H4 H3 H2 source fan or H1 Back-up er building fans or s H_hp W_hp HW_bu S_fan/ HW_hp bt_ HW_bu B_fan/ Figure 2: energy flow chart for the ing mode H1 H_hp H1 H source W_hp HW_hp H2 H_hp H 2 H source fan or W_hp S_fan/ HW_hp H 3 H source H3 fan or H_hp W_hp HW_bu Back-up er S_fan/ HW_hp HW_bu page 6 of 18 Version 2.0

7 D4.2. Concept for evaluation of H 4 H bt_ B _ fan/ source H4 fan or Back-up er building fans or s H_hp W_hp HW_bu S_fan/ HW_hp bt_ HW_bu B_fan/ page 7 of 18 Version 2.0

8 D4.2. Concept for evaluation of System boundaries cooling mode: C1 : This system contains only the cooling unit. C1 evaluate the performance of the refrigeration cycle. The system boundaries are similar to R defined in N [1], except that the standard takes, in addition, a small part of the consumption to overcome head losses, and most part of fan consumption. C2 : This system contains the cooling unit and the equipment to dissipate the energy. The system boundaries compares to SR ON in prn [2]. Note: R in N and SR ON in prn are more or less between C1 and C2 (see table 1 at the end of the document) C3 : This system contains the cooling unit, the equipment to dissipate the energy and all auxiliary drives of the cooling system. C3 represents the cooling system including all auxiliary drives which are installed in the cooling system. C4 : This system contains the cooling studied cooling system and possible additional cooling systems. In this analysis it is assumed that additional, supplementary, cooling systems are autonomous from the studied system. This level corresponds to the total cooling system performance for a building. C4 Supplementary cooling unit C3 C2 C1 cooling unit space cooling buffer Figure 3: xample scheme for a cooling system page 8 of 18 Version 2.0

9 D4.2. Concept for evaluation of calculation cooling mode: In this chapter the formulas for calculating the for cooling mode together with the energy flowcharts for the different system boundaries are described. C_BU C4 Supplementary cooling unit C_BU C3 C2 sink fan or C1 cooling unit building fans or s C S_fan/ CU bt_ B_fan/ Figure 4: energy flow chart for the cooling mode C1 C1 C CU sink cooling unit C CU C 2 C CU sink C2 fan or cooling unit C S_fan/ CU page 9 of 18 Version 2.0

10 D4.2. Concept for evaluation of C3 CU C bt _ B _ fan/ sink C3 fan or cooling unit building fans or s C S_fan/ CU bt_ B_fan/ C4 CU C bt_ C _ BU B _ fan/ C _ BU C_BU C4 Supplementary cooling unit C_BU C3 C2 sink fan or C1 cooling unit building fans or s C S_fan/ CU bt_ B_fan/ calculation simultaneous cooling and ing mode: For systems operating simultaneously in cooling and ing mode, e.g. for domestic hot water production, the fraction of delivered to the system has to be taken into account when calculating the different combined according to the system boundaries. page 10 of 18 Version 2.0

11 D4.2. Concept for evaluation of Operating modes The ing and cooling systems can be operated in different modes. The most common operating modes for combined systems can be defined as: space ing and domestic hot water operation cooling and domestic hot water operation space ing, cooling and domestic hot water operation Therefore the meters or flow meters and temperature sensors have to be integrated into the system as described in deliverable D4.1 - guideline for field measurements, to be able to evaluate the system efficiency according to the different system boundaries and depending on the operating modes. specially for Air to water systems the defrost mode has to be considered when calculating the. Space ing The system is operating in this mode to provide to the ing distribution system. Domostic hot water The system will operate in this mode to provide to the domestic hot water tank. For monobloc/compact s supplying space ing and domestic hot water, it is often due to practical reasons not possible to separate measurements of the delivered to space ing and to domestic hot water. In these cases the useful energy supplied by the can be identified in two ways: 1. By monitoring the total generated by the before the three-way valve 2. By monitoring the space output from the and to monitor the hot water consumed by the end user (flow and temperature), and to correct the useful energy by tank losses (based on lab measurements or calculations). The first option is the more accurate method, but needs intrusive measurements in the, which are costly and could affect end user guarantees. The second option is based on extremely good precision of the hot water measurements, and the use of either experience values or mathematical models for assessing the DHW tank losses. Depending on the installation location (living space or technical room) the useful energy can be calculated for space ing. Cooling The system will operate in this mode to cool the building. Defrost mode Air to water systems have to be operated in defrost mode for deiceing the evaporator in winter time when the air humidity causes icing of the out door exchanger. There are different possibilities for defrosting, the 3 most common strategies are: Direct electric defrosting Hot gas defrosting Reverce cycle defrosting page 11 of 18 Version 2.0

12 D4.2. Concept for evaluation of Direct electric defrosting For calculating the (Figure 5), the additional electrical energy demand for operating the defrost ing has to be added. As described in the chapter system boundaries the electric energy demand for defrosting should be a part of HW_hp. hp hp elec _ def Figure 5: direct electric defrosting Hot gas defrosting When calculating the for systems with hot gas defrosting (Figure 6) no additional measurement and calculation is necessary. The used hot gas for defrosting will decrease the ing capacity of the system, which will be recorded by the meter. hp hp Figure 6: hot gas defrosting Reverse cycle defrosting Systems with reverse cycle defrosting will extract from the ing system during defrost operation. This is not usable for the ing distrubtion system and has to be subtracted form the delivered to the system when calculating the. As described in Figure 7 it has to be differentiated between the out put of the ( hp ) and the useful delivered to the building by the ( hp-useable ). page 12 of 18 Version 2.0

13 D4.2. Concept for evaluation of hp hp_ def hp Figure 7: reverse cycle defrosting Comparison of the system- boundaries in standards and the system boundaries of the -calculation methodology There are different existing standards and regulations for calculating the. These calculation methodologies are mainly based on input from the testing standard N The system boundaries of testing standards are however focused on the ing or cooling unit itself. For comparing test results of the units with other units, the system integration is not taken into account. Therefore these standards do not include the entire energy consumption of the auxiliary drives on the sink and source side. The following descriptions show the differences between the system boundaries for field measurements and testing standards. The aim is to point out the difference between field testing and testing on a test rig, which does not necessarily mean that there should be no differences as this is not possible for practicable measurement systems in the field. The main difference of the evaluation methodologies is that testing is focused on the unit and the field measurements are focused on the system. For field measurements measuring the proportional energy input on the sink and source side requires high efforts for the measurement equipment and can not be realized within the common field measurement methodology. Hence the system boundaries for testing and field measurements will be slightly different, this has to be a taken into account when comparing calculated and measured. N 14511: This standard describes the testing procedure to calculate the COP or R. The average electrical power input of the unit within the defined interval of time is obtained from: the power input for operation of the compressor and any power input for defrosting; the power input for all control and safety devices of the unit and; the proportional power input of the conveying devices (e.g. fans, s) for ensuring the transport of the transfer media inside the unit. This equates to the system boundary of H1 / C1, with the difference being, that H1 / C1 does not include the proportional energy input of the auxiliary devices. N : This standard describes a calculation Bin method for energy consumption, starting from, among other, ing load evolution, ing curve of the, climate conditions and standard testing points. This method standardizes boundary contains the unit, the equipment to make the source energy available, internal and external boilers and back-up ers. This equates to boundary H4. The difference is that page 13 of 18 Version 2.0

14 D4.2. Concept for evaluation of H4 include the buffer tank that supplies water to the SH water circuit and that in the standard N the thermal losses of the ing system are calculated. Figure 8: system boundary N prn 14825: The calculation methodology and the measurement procedure of this standard are based on the standard N Therefore the auxiliary drives are mentioned partly in the SCOP calculation. SCOP NT is more or less similar to H2 and SCOP ON /SR ON to H3 / C2. prn makes a difference between SCOP ON / SR ON and SCOP / SR as they exclude electricity consumption of thermostat off mode, stand-by modes or crankcase er. Unlikely N , different running conditions are set, according climate (3 zones: cold, average, warm) and space ing emitters, what gives SCOP/SR for whose features are known at 6 tested conditions. uropean Directive 2009/125/C Lot 1: Calculation of energy consumption in Lot 1 is quite similar to prn 14825, except that demand included more items in addition to load, like buffer losses and distribution losses as it is mentioned in the N Lot 10: Similar to prn VDI : The calculation according to this regulation includes the source auxiliary drives, the back up er and the auxiliary drive energy for space ing (for page 14 of 18 Version 2.0

15 D4.2. Concept for evaluation of pressure losses of the condenser) as mentioned in the N This equates to the system boundary of H3, but the difference is the proportional energy input of the auxiliary devices on the sink side. The following table 1 gives an overview of the difference between the defined system boundaries for evaluating the measurement data and existing standards. Component H1/C1 N14511 N VDI prn14825* Lot 1 Lot 10 H2/C2 H3 H4/C3 Compressor x x x x x x x x x x Brine fan/ --- x x x head losses x x head losses head losses Back-up x x --- x x x x x Buffer tank SH DHW fans/s *refers to SCOP and SR head losses x --- x x x **see figure 5 (system boundary N ) head losses X** head losses head losses head losses head losses Table 1: comparison of system boundaries page 15 of 18 Version 2.0

16 D4.2. Concept for evaluation of Literature [1] N 14511, Air conditioners, liquid chilling packages and s with electrically driven compressors for space ing and cooling, March 2008 [2] prn 14825, Air conditioners, liquid chilling packages and s, with electrically compressors, for space ing and cooling- Testing and rating at part load conditions and calculation of seasonal performance, November 2009 [3] RS Directive, DIRCTIV 2009/28/C OF TH UROPAN PARLIAMNT AND OF TH COUNCIL, April 2009 [4] VDI , Calculation of s Simplified method for the calculation of the seasonal performance factor of s lectric s for space ing and domestic hot water, March 2009 [5] N , Heating systems in buildings Method for calculation of system energy requirements and system efficiencies Part 4-2: Space ing generation systems, systems, September 2008 page 16 of 18 Version 2.0

17 D4.2. Concept for evaluation of Annex calculation example xample-a: with energy supply ratio of 94 % additional electric ing additional gas ing additional solar ing H_hp [kwh] W_hp [kwh] HW_bu [kwh] * 1000 S_fan/ [kwh] B_fan/ [kwh] HW_hp [kwh] HW_bu [kwh] ** 25 *** * efficiency gas boiler 85 % ** measured fuel demand 121 m³ gas, calorific of gas 9,7 kwh/m³ *** electric energy demand of the circulating in the solar system H1 H 2 H H H 3 H 4 S _ fan / H H B _ fan / additional electric ing additional gas ing additional solar ing H1-5,0 5,0 5,0 H2-4,3 4,3 4,3 H3-3,6 3,4 4,5 H4-3,3 3,2 4,2 page 17 of 18 Version 2.0

18 D4.2. Concept for evaluation of xample-b: with energy supply ratio of 66 % additional electric ing additional gas ing additional solar ing H_hp [kwh] W_hp [kwh] HW_bu [kwh] * 5500 S_fan/ [kwh] B_fan/ [kwh] HW_hp [kwh] HW_bu [kwh] ** 140 *** * efficiency gas boiler 85 % ** measured fuel demand 667 m³ gas, calorific of gas 9,7 kwh/m³ *** electric energy demand of the circulating in the solar system H1 H 2 H H H 3 H 4 S _ fan / H H B _ fan / additional electric ing additional gas ing additional solar ing H1-5,0 5,0 5,0 H2-4,3 4,3 4,3 H3-2,0 1,8 6,2 H4-1,9 1,7 5,5 page 18 of 18 Version 2.0