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1/517Heat pumps sizing heat pump characteristics testing & operation conditions balance point storage size hydraulics
2/51Heat pumpQkrejected heatQ k Pel Q vsink sidePelQ kCOP PelQ v Q k Pel1 Qv Qk 1 COP source sideQvextracted heat
3/51Heat pumps: ground source (borehole)
4/51Heat pumps: ground source (ground HX)
5/51Heat pumps: water source (water well)
6/51Heat pumps: air source (ambient)
7/51Types of heat pumps on the market
8/51The trend is air source
9/51. also sanitary hot water HP increase
10/51Heat pumps market in Europe
11/51Top ten countries is the market
12/51Heat pump parameters heat output, heat capacity Qk [kW] – heat output from condenser coefficient of performance COP [-]at given boundary conditions tv1- tv1and- tk2- electric power Pel [kW]- evaporator input source output Qv [kW]tk2
13/51Air-water heat pump characteristics85air-waterair-water35 C35 C644COPe t [-][-]Q k, P el [kW]50 Ctk2350 C50 C2tk2235 C01-10-50t v1 [ C]510-10-50t v1 [ C]510
14/51electric power, heating capacity [kW]Air-water heat pump characteristicsconden.outputtemperatureambient air temperature
15/51COP [-]Air-water heat pump characteristicsambient air temperature
16/51Brine-water heat pump (ground source)126brine-waterbrine-water35 C1035 C550 Ctk26COPe t [-][-]Q k, P el [kW]8450 C4350 C2tk235 C02-505t v1 [ C]1015-505t v1 [ C]1015
17/51Brine-water heat pump (ground source)heating capacity [kW]conden.outputtemperaturesource temperature
18/51Water-water heat pumpheating capacity [kW]conden.outputtemperaturesource temperature
19/51Testing of heat pumps EN 14511 - Air conditioners, liquid chilling packages and heat pumpswith electrically driven compressors for space heating and cooling. EN 14511-1: dtto - Terms and definitions EN 14511-2: dtto - Test conditions EN 14511-3: dtto – Test methods EN 14511-4: dtto - Requirements EN 16147 – Heat pumps with electrically driven compressors.Testing and requirements for marking of domestic hot water units
20/51Testing conditions EN 14511: water-water W/W(W10 / W35) nominal: 10/35 C10/45 C operation:15/45 C10/55 C EN 14511: brine-water (ground-water) B/W nominal:0/35 C0/45 C operation:5/35 C5/45 C(B0 / W35)0/55 C-5/45 C EN 14511: air-water (ambient air) A/W(A2 / W35) nominal:7/35 C7/45 C operation:2/35 C2/45 C7/55 C-7/35 C-7/45 C-7/55 C-15/35 C-15/45 C
21/51Requirements on heat pump Quality label EHPA (European Heat Pump Association) minimum COP from testing according to EN 14511 in respected labbrine-waterB0/W35COP 4.3water-waterW10/W35COP 5.1air-waterA2/W35COP 3.1 declaration of sound power level documentation: planning, service and operation guides in local language customer service network, 24 h reaction time on customer complaints 2 years full warranty, spare parts inventory available for 10 years in stock21/26
22/51Seasonal performance factorhot waterSPFback-upspace heatingheat pumpCOPQsh,hwQHPQHPCOP Qel,HPSPF Q sh,hwQel,totQel,HPQel,auxQel,totQel,bu
23/51RES directive, minimum SPF heat pumps consume electric energy produced mainly from fossil fuels (primary non-renewable energysource)SPF 1,15he1heelectricity production efficiencyeuropean average 45.5 %SPF 2.5if SPF 2.5 . better to use fossil fuels directly by combustion
24/51EN 15450 – Annex C (informative)
25/51Operation modesmonovalent monovalent operation only heating deviceHP parallel bivalent operation under bivalent temperature(balance point) back-up heater isswitched-on low temperature systemsbivalent parallelBUHP
26/51Operation modesbivalent alternative alternatively bivalent operation under bivalent temperature back-upreplaced heat pump. for hightemperature heating systemsBUHPthe balance point temperatureunder which the back-up heater is required
27/51Operation modes monoenergetic operation e.g. bivalent operation of electric heat pump with electroboiler(integrated in one device) balance point according to heat output (dimensioning) acc. heating water temperature sufficient heat output from heat pump high temperatures of heating water needed, which couldnt besupplied by heat pump, esp. in extreme winter
28/51Heat pump sizing determination of heat pump type available heat source determination of (condenser) heat output Qk (for space heating) building heat loss heat output for hot water design flow temperature design source temperature
29/51Balance point according to temperatureexample of air source HP10090/70 C75/55 C9060/45 CTeplota přívodní vody [ C]flow temperature [ C]8055/40 Cradiators70max output temperature45/35 C35/30 C60504030underfloor heating20100-15-10-505Venkovní teplota [ C]10outdoor temperature [ C]1520
30/51Balance point according to heat outputheat output Q k [kW], heat load Q l [kW]30ground source HPQ25 L, desoutput temperature 35 Coutput temperature 50 Cheat loadQL2015Qk105balance point0-12-8-4048ambient temperature t e [ C]121620
31/51Balance point according to heat outputheat output Q k [kW], heat load Q l [kW]30air source HPQ25 L, desoutput temperature 35 Coutput temperature 50 Cheat loadQL20Qk,bal15Qk105balance point0-12-8-4048ambient temperature t e [ C]121620
32/51Balance point determination design heat load QL,des calculation according to EN 12 831 for design externaltemperature (e.g. -12 C, -15 C, -18 C in CZ ) heat output at balance point Qk QL e.g. from desired fraction 60 to 100 % Qk,bal / QL,desQL,desQk ,balQL t i t e,des t i t e t i t e,bal heat output Q k [kW], heat load Q l [kW]30output temperature 35 Coutput temperature 50 Cheat load2520151050-12-8-4048121620ambient temperature t e [ C]t e,bal t i Qk ,balQL,des t i t e,des if Qk konstif Qk / konst - graph
33/51Examplefamily housedesign load 15 kW fordesign temperature -15 Cheat pump (SE WPL18)heating system 50/40 Cdetermine the balance pointbalance point heat outputbalance point power inputbalance point COPQk 10.5 kW
34/51Flow temperature55tw 1 tw 1,des tw 1,des tw 1,min flow temperature [ C]5045t e t e,dest i t e,des42 C40flow tw13530return tw22520-15-10-505ambient temperature t e [ C]101520
35/51Power input at balance pointfor balance power pointtv1 -5 C, tk2 42 CP35 3.3 kWP50 4.5 kWinterpolationPtw1 P35 P50 P35 tw 1 3550 35Ptw1tw 1 35 P35 P50 P35 50 35balance power pointP42 3.9 kW
36/51ExampleCOPtw1 COP50 COP35 COP50 COP35COP5050 tw 150 35
37/51Examplefamily housedesign load 15 kW fordesign temperature -15 Cheat pump (SE WPL18)heating system 50/40 CQk 10.5 kWdetermine the balance pointbalance power pointbalance point heat outputP42 3.9 kWbalance point power inputbalance point COPbalance point COP
38/51Heat pump sizing – coverage of demand-12100%-10-8outdoor temperature te [ C]-675%-4-260%02450%681012010 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200 210 22025%days0%
39/51Heat pump sizing – coverage of demandsupplied energy by HPa r/ heating demand1,00,90,8residential sector0,7based on ,50,60,7a heating loadHP heating output / design0,80,91,0
40/51Heat pump sizing (ground source) dimensioning heat output (independent on ambient conditions) 50 % heat loss - coverage 85 % heat demand 60 % heat loss – coverage 93 % heat demand 70 % heat loss - coverage 97 % heat demandwater-water
41/51Heat pump sizing (air source) dimensioning heat output (dependent on ambient conditions) 50 % heat loss - coverage 75 % heat demand 60 % heat loss – coverage 85 % heat demand 70 % heat loss - coverage 92 % heat demandair-water
42/51Heating capacity control usual heat pumps start-stop regime cycling reduction of durability compressor elimination cycling undersizing heat storage – sizing of store for minimum operation time of heatpump heat pump with heating capacity control compressor speed control possibility for monovalent operation
43/51Heating capacity controlWithout capacity controlheat output Q k [kW], heat load Q l [kW]30output temperature 35 Coutput temperature 50 Cheat load2520backup15part load – cycling1050-12-8-4048121620ambient temperature t e [ C]backup100%With capacity controlpart load – cycling30%
44/51Heat storage for heat pump oversized storage for most of operation time balancing heat output and heat load reduction of frequency compressor on/off (1 x 10 min) longer durability of compressor heat source for outdoor units (air-water) antifreeze protection
45/51Heat storage for heat pump hydraulic decoupling of heat pump from load circuit hydraulic shunt heating systems can’t influence HP circuit providing required (higher) flowrates at condenserheatingsystemheat pumpstorage tank
46/51Sizing of storage tank balance to reduce on/off frequency minimum operation time period Dt increase of temperature Dt in store during operation of heat pump heat stored during operation of heat pumpQstored Q HP Dt V c Dt
47/51Sizing of storage tankspecific volumeDt [s]Dt [K]usuallyV1000 Dt QHP c Dtminimum operation time:increase of store temperature:15 min3-5K15 to 30 l/kWthermal capacity (momentum) of heating system results in lowervolume requirement
48/51Example calculate heat storage volume for balance point heat output 10.5 kW minimum operation time period Dt 15 min increase of temperature Dt in store 3 K1000 Dt V QHP c Dt1000 15 60V [m3 ] Q HP [kW ] 998 4187 3V 754 l
49/51Integration of storeelectronicallycontrolled pumpheat pumpcontroltemperature sensorpumpbypass valveheating systemstorage tank
50/51Hydraulics with two stores heating water store, hot water store bivalent (back-up) heater inside heat pumpHWEL.HEATERSHheatingsystemHWCW
51/51Hydraulics with central store hot water heated in heat exchanger immersed in heating water storevolume bivalent (back-up) heater: immersed in storeHWEL.HEATERheatingsystemCWHEAT PUMP
52/51Guides for design low temperature heating 45 C floor heating, wall heating radiators with larger surface pool water heating hot water low temperature 45 C air-water:advantage in summer, high ambient temperatures brine-water:reduction of borehole regeneration (!)
21/51 21/26 Requirements on heat pump Quality label EHPA (European Heat Pump Association) minimum COP from testing according to EN 14511 in respected lab brine-water B0/W35 COP 4.3 water-water W10/W35 COP 5.1 air-water A2/W35 COP 3.1 declaration of sound power level documentation: planning, service and operation guides in local language
