compression chiller. - … closed cycles liquid sorbent solid sorbent absorption
chiller adsorption chiller desiccant and evaporative cooling (DEC) liquid sorbent.
New absorption chillers for high efficient solar cooling systems
New absorption chillers for high efficient solar cooling systems Dipl.-Ing. Stefan Petersen & Dipl.-Ing. Jan Albers
Foto: TU Berlin
Foto: TU Berlin
1. 2. 3. 4.
General Technology Overview Operating data Solar cooling system layout Showcase results
Technische Universität Berlin • Institut für Energietechnik
1
New absorption chillers for high efficient solar cooling systems
Solar air-conditioning technologies electrical systems - PV + Vapor compression chiller -…
thermal systems
heat transformation processes
thermomechanical processes - steam jet cycles
closed cycles
open cycles
- rankine cycle + vapor compression chiller -…
liquid sorbent
solid sorbent
absorption chiller
adsorption chiller
liquid sorbent
solid sorbent
desiccant and evaporative cooling (DEC)
Technische Universität Berlin • Institut für Energietechnik
2
New absorption chillers for high efficient solar cooling systems
Basics –compression chiller inner cycle condenser
steam
cooling water refrigerant throttle
compressor electric power
chilled water evaporator
steam
water-cooled vapor compression chiller [1] liquid refrigerant
vaporous refrigerant
[1] Carrier
Technische Universität Berlin • Institut für Energietechnik
3
New absorption chillers for high efficient solar cooling systems
Basics – absorption chiller inner cycle condenser
steam
desorber hot water
cooling water
refrigerant throttle
Chilled water evaporator
steam
absorber cooling water
10 kW Phönix-absorption chillerTU Berlin
refrigerant
Technische Universität Berlin • Institut für Energietechnik
diluted solution
concentrated solution
4
New absorption chillers for high efficient solar cooling systems
Short general characteristic 70
0.9 0 , 8
Cooling Capacity [kW]
60
New 50 kW Chiller
0.8
0 , 7
0.7
50
0.6 High efficient10 kW
40
0 , 5
0.5
0 , 4
0.4
30
0 , 3
0.3
20
0 , 2
Nominal load
0.2
10
0.1
0
0.0 24
29
34 39 44 Reject Heat Inlet Temperature [°C]
Technische Universität Berlin • Institut für Energietechnik
49
5
COP [-]
0 , 6
New absorption chillers for high efficient solar cooling systems
System setup – thermal system configuration Heat transformation process
Basic system configuration Storage almost inevitable Technische Universität Berlin • Institut für Energietechnik
6
New absorption chillers for high efficient solar cooling systems
Variability Driving Heat Source I @ t_RH=30°C, V_RH=3,8kg/s, t_CW=21/16°C
Cooling Capacity [kW]
70 0,9 l/s 0,6 l/s
60 50
dT@40kW 13K
40
40K 0,3 l/s
30 0,1 l/s
20 10 0 50
60
70 80 90 Heat Source Inlet temperature [°C]
Technische Universität Berlin • Institut für Energietechnik
100
7
New absorption chillers for high efficient solar cooling systems
Variability Driving Heat Source II @ t_RH=30°C, V_RH=3,8kg/s, t_CW=21/16°C
0.9 0.8 0.7
dt in/out < 13K@77/64 ….. to.. ≈ 40K@97/57
COP [-]
0.6 0.5 0.4
Volume flow 0.9 l/s Volumenstrom
0.3
Volume flow 0.6 l/s Volumenstrom Volume flow 0.3 l/s Volumenstrom
0.2 0.1 0.0 0
10
20
30
40
Cooling capacity [kW]
Technische Universität Berlin • Institut für Energietechnik
50
60
70 8
New absorption chillers for high efficient solar cooling systems
Variability Reject Heat Sink I @ t_DH=90°C, V_DH=0,9kg/s, t_CW=21/16°C
60 3,8 l/s Cooling Capacity [kW]
50 2,0 l/s 40
1,5 l/s
30
Phydraulic = nominal =100%
1,0 l/s
20
Phydraulic = 1/64*nominal = 1.5%
10 0 25
30 35 40 Reject Heat Inlet Temperature [°C]
Technische Universität Berlin • Institut für Energietechnik
45 9
New absorption chillers for high efficient solar cooling systems
Energetic comparison including auxiliaries 2
auxiliary power demand pa=0
pa=1%
1,5 pa=10% break even
1
0,5
0 0
0,2
0,4
0,6
0,8
1
Solar fraction Technische Universität Berlin • Institut für Energietechnik
10
New absorption chillers for high efficient solar cooling systems
SAC-System UBA Dessau
image source: Busse
Technische Universität Berlin • Institut für Energietechnik
11
New absorption chillers for high efficient solar cooling systems
Concept for solar cooling system
(Dry) reject heat device
KKM
Compression chiller
District heating
AKA
Solar Collectors
Hot water storage
Absorptionschiller
Technische Universität Berlin • Institut für Energietechnik
Cold Chilled water consumer storage
12
New absorption chillers for high efficient solar cooling systems
SAC-System UBA Dessau
Temperature collector outlet Temperature top of storage
Solar driving temperature
Technische Universität Berlin • Institut für Energietechnik
Chilled water outlet
13
New absorption chillers for high efficient solar cooling systems
Operating data and control Temperatur / °C, Volumenstrom / (m³/h), Strahlung / (10 W/m²)
100 solar Solar Antriebstemperatur driving temperature
90 80 70
Temperatur Kollektoraustritt Temperature at collector outlet
Temperature Temperatur at Speicher 1 oben top of storage Solarstrahlung Horizontal horizontal
60
irradiation
50 40 30
Flow rate in collector circuit Volumenstrom Kollektorkreis
20 10 0 04:00
Entladevolumenstrom Driving flow rate to chiller 08:00
12:00 16:00 Uhrzeit am 03.09.2011
Technische Universität Berlin • Institut für Energietechnik
20:00
14
New absorption chillers for high efficient solar cooling systems
Regelung und Betriebsergebnisse 100 Temperatur / °C, Leistung / kW
90 80
Driving temperature Antriebstemperatur
70
Reject heat inlet temperature Temperatur Kühlwasser Eintritt
60 Antriebstemperatur Driving temperature (Sollwert) (set point
50 40
Cooling load(Sollwert) (set value) Kälteleistung
30 20 10
Cooling load Kälteleistung Reject heat inlet temp.(Sollwert) (set value) Temperatur Kühlwasser
0 04:00
08:00
Temperatur Kaltwasser Austritt Chilled water temperature
12:00 16:00 Uhrzeit am 03.09.2011
Technische Universität Berlin • Institut für Energietechnik
20:00
15
New absorption chillers for high efficient solar cooling systems
Results of first year Previous year with adsorption chiller Aug. 2010 – Jul. 2011
Change First year with new absorption chiller Aug. 2011 – Jul. 2012
Cold generation
104 MWh0
59 MWh0
Driving heat
221 MWhth
80 MWhth
Thermal efficiency
0,47 MWh0/MWhth
0,76 MWh0/MWhth
+62%
Electrical efficiency
2,9 MWh0/MWhel
4,5 MWh0/MWhel
+55%
Water consumption
4,0 m³/MWh0
1,3 m³/MWh0
68%
Technische Universität Berlin • Institut für Energietechnik
16
New absorption chillers for high efficient solar cooling systems
Control Issues: Parasitic electricity consumption
Control Strategy
SEERel
SEERth
Classic
12,4
0,76
+Reject heat, vol.flow
17,8
0,75
+Hot Water, vol.flow
13,6
0,76
+vol.flows +reject heat temp.
20,1
0,75
SEER = Seasonal Energy Efficiency Ratio Technische Universität Berlin • Institut für Energietechnik
17
New absorption chillers for high efficient solar cooling systems
Conclusion Development started in 2008 with case studies and optimization: - Thermodynamic design - Manufacturing process - Cost efficiency Final chiller concept fixed in 2009 Starting of pre-industrial manufacturing and laboratory measurements in 2010 Installation of first prototypes in Berlin and Dessau in 2011 Commercial launch in 2013: - high energy efficiency (COP > 0,75) - high energy density and compactness - high cooling water temperatures > 45°C - low driving temperatures (tstart < 60°C) - low investment (~300 €/kW) Technische Universität Berlin • Institut für Energietechnik
Foto: TU Berlin
18