Solar Cooling Technologies & Applications Christodoulaki Rosie PhD cand. Mech. Eng. MSc Environmental design & engineering BSc Physics
Solar Cooling Technologies 1.
Closed Cycle i. ii.
2.
Absorption Chillers Adsorption Chillers
Open Cycle i. ii.
Solid Desiccant Evaporative Cooling Liquid Desiccant Evaporative Cooling
chilled water
heat
Thermal driven cooling process conditioned air Source : Fraunhofer ISE, Solarnext
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Closed Cycle Systems - Absorption/Adsorption - Refrigerant medium: Water - Production of chilled water - Possible use of existing fan coils, chilled ceilings, underfloor heating.
~18°C
Driving temperature > 60°C
Chilled ceiling
Supply air system
Fresh air 15 - 18°C (< 12°C)
Absorption / Adsorption Chiller
Fan coil
6 - 9°C
(thermally driven)
Conditioned area
Chilled water temperature
Source : Fraunhofer ISE
Single effect absorption process driving heat (e.g. solar collector)
pressure
heat rejection (cooling tower) condenser
throttle
useful cold
generator
solution pump solution heat exchanger
vapour evaporator
vapour
absorber
heat rejection (cooling tower) temperature
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Open Cycle Systems -
Driving temperature > 50°C
Liquid/Solid DEC Refrigerant medium: Water Production of conditioned air Possible use of existing fan coils.
Return air
Supply air
Conditioned area
Desiccant Evaporative Cooling (DEC)
Source : Fraunhofer ISE
Thermodynamic Processes driving heat high temperature, TH environment, e.g. cooling tower
solar collector heat rejection intermediate temperature, TM air-conditioning system
Coefficient of useful cooling low temperature, TC
Performance (COPthermal) = useful cooling driving heat Source : Fraunhofer ISE
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Solar Cooling Systems Overview
Source : EU Altener Project Climasol
Efficiency – Operational temperature, 2007 Open systems Liquid DEC: Τ = 60C, COP = 0.7 Solid DEC: T = 80C, COP = 0.5 Closed systems Absorption: Τ = 75C, COP = 0.7 Adsorption: T = 55C, COP = 0.5
Initial cost – Collector area needed, 2007. Open systems Liquid DEC: 4500 €/kW, 5 m2/kW Solid DEC: 3500 €/kW, 0.5 m2/kW Closed systems Absorption: 2000 €/kW, 4 m2/kW Adsorption: 5500 €/kW, 2.5 m2/kW
Source : CA Balaras, G Grossman, HM Henning, Solar Air-Conditioning in Europe - an overview, Renewable Energy & Sustainable Energy Reviews, 11, 2007, 299-314
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Solar Cooling Systems installed in Europe - Absorption: 58% - Solid DEC: 23% - Adsorption: 12% - Liquid DEC: 4%
collector area
0.6%
desiccant, liquid
cooling capacity
1.5%
number of systems
4.4%
8.7%
desiccant, rotor
14.1% 23.5%
32.7%
adsorption
26.3% 11.8%
57.8%
absorption
57.9% 58.8%
0.0%
10.0%
20.0%
30.0%
40.0%
50.0%
60.0%
70.0%
Source : HM Henning, Solar Assisted air conditioning of buildings – an overview, Applied Thermal Engineering, 27, 2007, 1734-1749.
Solar Cooling Applications
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PENA, CRES technological park, Athens, El PENA, Lavrio Solar cooling Solid DEC system Demo & research application for CRES In operation since
2007
Air conditioned area
84m²
Collector type
10 m2, Calpak flat-plate
Collector fluid
water-glycol 60°C
Operation temperature
1100 m3/h
Nominal air flow rate Min. air volume flow rate Desiccant cooling system Brand of desiccant unit
373 m3/h solid LiCl Klingenburg
Sarantis, Cosmetics industry, Inofita Viotias, El Operation 1999 - One of the largest installations in the world - 2,700 m2 flat plate collectors (SOLE) - 2 adsorption cooling machines, 350 kW cooling each - 3 compression cooling machines, 350 kW
Cost
Solar
Others sonstiges 6% 6%
Sub-structure for collectors Unterbau für 5% Kollektoren 5%
Solarkollektoren collectors 28% 28%
AdsorptionsAdsorption kältemaschinen cooling 20% machine
20%
Rückkühlwerke Cooling tower 6%
6%
Regelung, control Monitoring Monitoring 5% 5%
Installations-
Installation kosten Costs 20% 20%
Öl befeuerte Oil-driven Kessel als boiler Back-Upas back-up 10%
10%
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GICB wine cellar Banyuls/mer, Fr
-130 m² evacuated tube collectors - 52 kWcooling - Investment cost: 1,6 MF (1991)
Source : TECSOL
DIREN Guadeloupe, Fr - Chilled surface: 570 m² - 61 m² evacuated tube collectors - 35 kWcooling - Absorption chiller
Source : TECSOL
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Collectors 57%
Technical room 4%
Solar collectors Technical room Cold production Condensation Electricity Monitoring Startup Total HT: €. HT / kWf
Collectors (€ / m²)
€. HT 89 314 6 065 32 263 9 920 13 108 8 422 610 159 701 4 563
1 441
Cold production 20%
Startup 0% Condensation 6% Monitoring 5%
Electricity 8%
Source : TECSOL
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Cosmetic laboratory, Sophia Antipolis, Fr
- 570 m² evacuated tube collectors - 210 kW cooling - Investment cost: 2500 € / kWf
Academic Hospital of Freiburg, De
-
-
-
Adsorption cooling: 70 kWcooling Evacuated tube collectors direct flow: initially 90 m2, then increased at 170 m2 (2001) Air flow: 8000 m3/h
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Thank you for your attention!
Centre for Renewable Energy Sources Solar Thermal Department 19klm. Marathonos av., 19009, Pikermi tel. 00302106603300, fax. 00302106603301 www.cres.gr Rosa Christodoulaki
[email protected]
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