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i iRepetition
Werner WeissAEE - Institute for Sustainable TechnologiesA-8200 Gleisdorf, Feldgasse 2AUSTRIA
Achievements - 2009Achievements 2009
Total Capacity in Operation [GW ], [GW ] and Produced Energy [TWh ], [TWh ], 2008el th el th B 340.0
300
325
350
Total capacity in operation [GW] 2009P d d E [TWh] 2009heat power
225
250
275Produced Energy [TWh] 2009heat power
158.0
189.0
137.0150
175
200
83.075
100
125
11.023.0
0.7 0.5
24.01.8 0.7
0
25
50
S l Th l Wi d P G th l Ph t lt i S l Th l O Tid lSolar ThermalHeat
Wind Power GeothermalPower
Photovoltaic Solar ThermalPower
Ocean TidalPower
Distribution of Collectors
Unglazed Collector Air collector Flat plateUnglazed Collector12.4%
Air collector0.8%
Flat-plate32.6%
-4.5%0%
+4.5%
Evacuated tube54 2%54.2%
Solar Heat Worldwide - 2008Solar Heat Worldwide 2008
Installed Capacity [MW ]th
13,500
15,000
Installed Capacity [MW ]th
unglazed glazed evacuated tube9.
7
10,500
12,000
80,3
2
6,000
7,500
9,000
3,000
4,500
6,000
0
1,500
China UnitedSt t
Germany Turkey Australia Japan Brazil Austria Greece IsraelStates
Installations by Economic Region 2008Installations by Economic Region 2008FlatFlat--plate and Evacuated Collectorsplate and Evacuated CollectorsFlatFlat--plate and Evacuated Collectorsplate and Evacuated Collectors
C t l + S th A iCentral + South America1.7%
AsiaEurope14.5%
Middle East0.8%
Australia + New Zealand
Others6.1%
1.7%
China78.9%
Australia + New Zealand0.8%
United States + Canada0.6%Japan0.5%
Africa0.3%0.3%
Annually installed capacity of flat-plate and evacuated tube collectorsand evacuated tube collectors
Installed capacity [kW /a/1,000 inh.]th
15 016.017.018.0
p y [ , ]
Middle East ChinaAustralia + New Zealand EuropeCentral and South America Africa
11 012.013.014.015.0
Japan United States+CanadaAsia
8.09.0
10.011.0
4.05.06.07.0
0 01.02.03.0
0.02000 2001 2002 2003 2004 2005 2006 2007 2008
Distribution of different solar thermal systems by economic regionsystems by economic region
90%
100%
Thermosiphon Systems Pumpe
70%
80%
90%
50%
60%
20%
30%
40%
0%
10%
20%
United States Europe Australia Japan Brazil China
Distribution by ApplicationDistribution by Application World’s Top 8 Countries / Related to newly installed capacity in 2008
Source: Weiss, W., Mauthner, F.: Solar Heat Worldwide, IEA SHC 2010
Cooling Systems 2009Cooling Systems 2009
Source:www.greenchiller.eu.
ApplicationsApplications
Solar Water Heating Systems
G it d i tGravity driven systems
fsol = 70 – 90%
700 1000 kWh/kW700 – 1000 kWh/kWth
Solar Water Heating Systems
Solar Water Heating Systems
Three different types of evacuated tube collectors:
all-glass U-tubeU tube heat-pipe
Pumped SWH Systems
12
1
2
6 3
7 11
5109
8
64
3
8
Small-scale Systems for Hot Water Preparationy
fsol = 80 – 90%
800 – 1000 kWh/m² collector area (Southern Africa)
Combined SWH and CoolingCombined SWH and Cooling
Solar Air Conditioning and CoolingSolar Air Conditioning and Cooling
Source : Fraunhofer ISE, Solarnext
Solar Cooling System for the German BMVBWSolar Cooling System for the German BMVBW
Solar Collectors for Cooling
Source: Jan Albers, IMBE, TU Berlin
Solar Combi Systems for SFHfsol = 50 – 90%
y
500 – 600 kWh/m² (Southern Africa)
Large-scale solar heating systemsLarge scale solar heating systems
Solar District HeatingSolar District Heating
S l i ld 400 460 kWh/ ²Solar yields: 400 – 460 kWh/m².a
Marstal Denmark 12 8 MW (18 365m2)Marstal, Denmark 12.8 MWth (18.365m )
Tyras Dairy, Trikala, GreeceTyras Dairy, Trikala, Greece
Textile Industry Hangzhou China 13000㎡ (9 MW )Textile Industry Hangzhou China 13000㎡ (9 MWth)
SEA WATER DESALINATIONSEA WATER DESALINATION
Pilot System Spain, CIEMAT, INETI252 CPC AO SOL (499 m²)
SOLAR RADIATION - 1SOLAR RADIATION - 1
SOLAR CONSTANTSOLAR CONSTANT1360 W/m²
GLOBAL IRRADIATIONGLOBAL IRRADIATION800 - 1000 W/m²
SOLAR RADIATION - 2SOLAR RADIATION 2
Clear, blue sky Scattered clouds Overcast sky, y
y
Solar irradiance [W/m²] 600 - 1000 200 - 400 50 - 150
Diffuse fraction [%] 10 - 20 20 - 80 80 - 100
Global irradiance and diffuse fraction, depending on the cloud conditions
SOLAR RADIATION - 7SOLAR RADIATION 7
Jan Feb Mar April May June July Aug Sep Oct Nov Dec Year Lat
Vienna, Austria 25.2 43 81.4 118.9 149.8 160.7 164.9 139.7 100.6 59.8 26.3 19.9 1090 48.2 N
Kampala UG 174 164 170 153 151 142 141 151 155 163 154 164 1882 00 2 N
Average monthly and yearly values of global solar radiation on a horizontal surface in kWh/m²
Kampala, UG 174 164 170 153 151 142 141 151 155 163 154 164 1882 00.2 N
Johannesburg 215 185 183 144 135 119 132 158 189 200 197 218 2076 26.1 S
g y y y g
Depending on the geographic location the yearly global insolation on a horizontal surface may vary betweeninsolation on a horizontal surface may vary between 1000 and 2200 kWh/m2
ANGLE OF TILTANGLE OF TILT
Latitude [degree]
Best collector tilt in:
June Orientation Sept./March Orientation December Orientation 50 N 26.5 S 50 S 73.5 S 40 N 16 5 S 40 S 63 5 S40 N 16.5 S 40 S 63.5 S30 N 6.5 S 30 S 53.5 S 20 N 3.5 N 20 S 43.5 S 15 N 8.5 N 15 S 38.5 S 10 N 13 5 N 10 S 33 5 S10 N 13.5 N 10 S 33.5 S
Equator = 0 23.5 N 0 - 23.5 S 10 S 33.5 N 10 N 13.5 S 15 S 38.5 N 15 N 8.5 S 20 S 43.5 N 20 N 3.5 S30 S 53.5 N 30 N 6.5 N 40 S 63.5 N 40 N 16.5 N 50 S 73.5 N 50 N 26.5 N
Maputo: Latitude -25.9
Cape Town: Latitude - 34
As a general rule, the optimum angle of tilt is equal to the degree of latitude of the site
TYPES OF COLLECTORSTYPES OF COLLECTORS
FLAT-PLATE COLLECTORFLAT PLATE COLLECTOR
TransparentTransparent cover
Absorber plate
Insulation
Tubes
Source: Consolar
Evacuated Tube Collectors – Heat Pipe p
Absorber MaterialAbsorber Material
Aluminum or Copper?
37%
63%
Aluminum
Copper
Source: Sonne, Wind und Wärme, 2009
Copper
ABSORBER COATINGABSORBER COATING
Selective coating: 0 < 0.2, > 0.9
Partially selective coating: 0.2 < 0.5, > 0.9
Non selective coating: 0.5 < 1.0, > 0.9Non selective coating: 0.5 1.0, 0.9
Plain copper black paint galvanic coating physical vapour pp p g g p y pdeposition or sputtering
COLLECTOR MATERIALS
??
ABSORBER MATERIALS THERMAL CONDUCTIVITYTHERMAL CONDUCTIVITY
absorber material thermal conductivity[W/mK][W/mK]
steel 50steel 50
aluminium 210
copper 380pp
TRANSPARENT COVER MATERIALSTRANSPARENT COVER MATERIALS
cover thickness [mm]
weight [kg/m²]
solar transmittance
Standard glass *) 4 10 0.84g )Standard glass, tempered 4 10 0.84 Iron free glass, tempered 4 10 0.91 Antireflective coated glass 4 10 0.95Antireflective coated glass 4 10 0.95PMMA, ducted plate 16 5.0 0.77 PMMA, double ducted plate 16 5.6 0.72
*) danger of breaking determined by high collector temperatures
TRANSPARENT COVER MATERIALSTRANSPARENT COVER MATERIALS
ion
AR coatedsmis
s
Uncoatedar tr
ans
Uncoated
Sola
Incident angle(42)
Physical Processes inside a Flat-Plate CollectorPhysical Processes inside a Flat Plate Collector
heat loss throughthe pane of glass
reflection on the
the pane of glassreflection on absorber
reflection on thepane of glass
occurrenceoccurrenceof solar radiation heat loss through the
rear and side walls
Losses of a basic Flat-plate CollectorLosses of a basic Flat plate Collector
Source: Source: Wagner & Co.
Characteristic Values of Flat-plate and E t d T b C ll tEvacuated Tube Collectors
Qcoll is the energy collected per unit collector area per unit timeQcoll is the energy collected per unit collector area per unit time
FR is the collector’s heat removal factor
τ is the transmittance of the cover
α i h h b i i f h b bα is the shortwave absorptivity of the absorber
G is the global incident solar radiation on the collector
UL is the overall heat loss coefficient of the collector
ΔT is the temperature differential between the heat transfer fluid entering the collector and the ambient temperature outside the collector.
Collector Efficiency Curvey
(tm – ta)/G [Km²/W]
Collector EfficiencyCollector Efficiency
eEnergieeingesetzteNutzenergi
useful energy
solar energyeEnergieeingesetztsolar energy
tta
tta amam )²()(
210
G
aG
a 210
Collector EfficiencyCollector Efficiency
s. T-Sol Collector data
Collector efficiency curvey
Optical Losses
0,7
0,8Optical Losses
0,5
0,6
Thermal Losses
0,3
0,4eta
Useful Energy
0,1
0,2
gy
00 0,04 0,08 0,12 0,16
Stagnation Point
(TKm-TA) / GT [Km²/W]
Efficiency of different collector types (calc)Efficiency of different collector types (calc)
Evacuated Tube Collector
Selective Flat-plate Collector
Uncovered Absorber
Simple Flat-plate Collector
(tm – ta)/G [Km²/W]
Capacity of a Water Storage (calc)Capacity of a Water Storage (calc)
THERMOSYPHON SYSTEMSTHERMOSYPHON SYSTEMS
insulation
float valve
cold water inletoverflow
pipe
hot waterhot water outlet
collector
Hot water storage for a thermosyphon systemfor a thermosyphon system
1 Coating
2 Insulation
3 Steel tank
4 Enamel coating
5 Electric heating element
6 Sacrificial anode
7 Thermostat
8 Double Jacket Heat Exchanger
9. Cold water inlet
10. Hot water to user
11. Heat exchanger inlet
12. Heat exchanger outlet
13. Heat Exchanger Safety ValveSource: Chromagen
Domestic Hot Water TankDomestic Hot Water Tank
Hot water tanks with stratification devicesHot water tanks with stratification devices
Sources from left to right: Solarklar, TiSun and Solvis