Solar Thermal Technology

Transcription

1 Energy Solar Thermal Technology Status and Perspectives Gerhard Stryi-Hipp Fraunhofer Institute for Solar Energy Systems ISE Warsaw, 15 November

2 Solar Thermal Energy: Underestimated Source of Power Source: IEA-SHC Solar Heat Worldwide, Edition 2011,

3 Solar Thermal World Market 2009 New Installed Collector Capacity Quelle: IEA SHC-Programm, Solar Heat Worldwide, Edition 2011

4 Flat Plate Collector - Construction n Typical high efficient aluminium framed flat plate collector Absorber from Copper or Aluminium, selective coated: high absorption of sunlight low emission of infrared-radiation Low iron solar glass = improved transparency Sometimes AR anti reflective coated Copper tubes ultrasonic or laser welded Adapter plate Aluminium profile Insulation Aluminium back board Insulation Aluminium frame Connection tube Source: GreenOneTec

5 Flat Plate Collector - Construction n Typical high efficient wooden framed flat plate collector Connection tube Aluminium profile Glass sealing Selective coated absorber Solar glass Adapter plate Insulation Wood frame Wooden back board Collecting pipe Source: GreenOneTec

6 Solar Domestic Hot Water System forced circulation Solar radiation Hot drinking water outlet Typical system in Germany (4 person household): Forced circulation 5-6 m² collector area 300 liter storage tank Glazed solar collector Flat plate collector or Evacuated tube collector Pumped solar circuit - Anti freeze heat transfer fluid - Controller - Pump - Safety (pressure) valves Solar heat store with two heat exchangers Cold drinking water inlet Auxiliary heating via natural gas, oil, wood, district heating, electricity,

7 Thermosiphon Solar Domestic Hot Water Systems are mainly used in southern countries Typical system for Southern Europe: Thermosiphon system 2-4 m² collector area liter storage tank Natural circulation Natural convection: The solar heat expands the heat transfer fluid, becomes lighter and rises to the storage tank above. Source: Schueco

8 Typical Solar Thermal Combi-System for domestic hot water and space heating Typical system in Germany: m² collector area liter storage tank % solar fraction Main store contains heating water (buffer) Domestic hot water tank contains drinking water Space heating circuit (water system) Combi-store

9 Typical Large Solar Thermal Systems Collector Loop freeze protected Solar Heat Store buffer water Domestic Hot Water supply Collector inlet temperature must be as low as possible (store stratification!) -> high collector efficiency Charge and discharge devices and strategy must lead to a good temperature stratification Cold water supply must cool down the bottom of the buffer store via heat exchanger for a high solar collector efficiency

10 Solar Thermal Technology Platform Support of technological development in Europe and Germany Concept to accelerate technological development Researcher Politicians Solar Thermal Vision 2030 Role of solar thermal energy in 2030, which technologies will be used? Industry Strategic Research Agenda Which R&D is necessary to let the vision become reality? Solar Thermal Research Agenda published in Dec 2008: Implementation Stimulation of new R&D programs, political advice, lobbying,

11 Structure n Solar Thermal is part of the European Technology Platform on Renewable Heating & Cooling n RHC-Platform is supported by the European Commission

12 Solar Thermal Vision 2030 of the Solar Thermal Technology Panel of the European Technology Platform on RHC n n n n New buildings: Active Solar House - 100% solar heated buildings will be the building standard Existing building stock: Solar Refurbishment - Solar refurbished buildings > 50% solar heated, will be the most cost effective way to refurbish the building stock Commercial + Agricultural Solar Applications - Solar thermal systems will cover process heating and cooling demands Solar district heating and cooling networks - will be widely solar assisted Source: Solifer Source: Schüco Overall goal: ca. 50% of the low temperature needs (up to 250 C) will be provided by solar thermal Source: Solvis

13 Four Strategies to develop the full potential of ST 1. The number of solar thermal systems has to be sharply increased => lower costs for standard technology, 2. The share of solar thermal energy per building has to be increased step-by-step up to 100% => system technology, storage tanks, 3. ST has to be introduced in new market segments like public buildings and the commercial sector => Adapted collector & system technology, 4. New technologies & applications have to be developed like solar assisted cooling and district and process heating => Adapt ST and application technology

14 From SDHW only.. to 100% Solar Heated Houses SDHW solar domestic hot water heating 10%-20% SDHW + space heating support 20%-30% Solar Active House mainly heated by solar SDHW + space heating support (large share) 50% % 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% Share of solar thermal energy in the heat demand of a building

15 Concept of Solar Heated Building Solar Thermal Collectors 30m² - 60m² Seasonal Heat Storage (Water) 6 10 m³ Solar Fraction (share of the overall heat demand): 60% - 70%

16 Large Solar Thermal Systems n For multi family homes, hotels, hospitals, nursing homes n Crucial: management of the different heat sources Image: Solvis Image: Wagner & Co

17 Promising Technology Solar Assisted Cooling n (Solar) thermally driven cooling machines n Cooling demand and solar supply patterns match well n There are already more than 400 pilot systems installed in Europe n Small systems are under development Adsorption cooling machine Building: Governmental Press Office Berlin Building: IHK Freiburg Source: Viessmann Source: Fraunhofer ISE

18 Promising Application Solar District Heating - will play a big role in the future Semi-detached houses in Neckarsulm, Germany Solar District Heating, Marstal, Denmark collector area 17,000 m² Arcon 12,000 m³ seasonal storage, Friedrichshafen, Germany Solites Solites

19 German Strategic Research Agenda on Solar Thermal Energy Developed by the German Solar Thermal Technology Platform DSTTP download: 19

20 Solar Thermal R&D topics covered Solar Thermal Collectors Thermal storages for single buildings Seasonal thermal storages for district heating grids System technology Solar process heat Solar cooling and refrigeration 20

21 ST flat plate collectors: R&D goals Overall goals: Cost reduction, integraton New materials - plastic, steel,... New production methods - absorber, housing,... Security, operation - avoid stagnation (switchable,..) Adapted to the application - low - high temperature - Roof / facade integration Special constructions - Air collectors - PV-Thermal hybrid collectors - Integrated storage collectors 21

22 Combi-system technology: R&D topics Goals: cost reduction, increased solar fraction (fsave: 20-30% in a well-insulated one-family home in central Europe) Improved system and storage tank design Improved controller Optimized system (solar thermal + fossil/ pellets/heat pump/...) Increased operation security

23 Conclusions n Solar thermal technology is a well established technology in Germany n Solar thermal energy can cover up to 50% of the overall energy demand for heating and cooling in Germany n Solar thermal technology has still a great potential for technological development, R&D activities are increasing n German companies do have a huge experience in system technology and offering high quality components and products for solar thermal systems

24 Thank you very much for your attention!