Heat storages 1 Doz. DR.-Ing. D. SCHMIDT, Solarzentrum Wietow Warehouses heat – whether it is possible to use winter heat stored during the summer ? 1
It is possible to use winter heat stored during the summer ? Heat storages2 The simple answer… Yes we can !!!
WHAT DO WE NEED ? Low energy buildings Low energy heating systems Heat storages3
Application Radiation heating Radiation cooling Heat storages4 Flat invisible structure Optimized heat distribution responsive comfortable Maintenance-free Economically Environmentally friendly savely Very low flow temperatures
SOLARTHERMAL SYSTEMS WITH WARM WATER AND HEATING SUPPORT Heat storages5 And the storages ?
THE PROBLEMS Storage offen to small Bad thermal stratification Standstill losses (2-8 K/d) Insufficient insulation No long-therm storages High entry flow temperatures for heating systems Solar collectors for winter time (inclination) Heat storages6
7 Temperature losses per day (K) Capacity up to 30 o C (d) storage 400 l, d=100mm,Ts=80Tu=20 Tv=3,514 D/H=5Ts=60Tu=20 Tv=2,313 Reflections on temperature losses PU-rigid foam (thermal conductivity : 0,035 W/m K). Temperature losses per day (K) Capacity up to 30 o C (d) l d=100mm,Ts=80Tu=20 Tv=1,1926 Ts=60Tu=20 Tv=0,7937 We must storage more !
CONCEPTS FOR SEASONAL HEAT STORAGE IN DISTRICT HEATING SYSTEMS Heat storages8 Hot water storage Gravel-water-storage Geothermal probes storage Aquifer storage For private (small) applications: too large, too expensive
SOME EXPERIENCES WITH STOREGES AT THE SOLARCENTER IN WIETOW Heat storages9 Wietow
SPECIAL SOLAR COLLECRTORS Heat storages10 for roofing for winter time: Vacuum concentrator flat plate collector
INFRARED REFLECTION „LUPOTHERM“ Heat storages11
12Heat storages Temperature losses per day (K) Capacity up to 30 o C (d) storage 400 l, d=100mm,Ts=80Tu=20 Tv=3,514 D/H=5Ts=60Tu=20 Tv=2,313 Temperature losses per day (K) Capacity up to 30 o C (d) l d=100mm,Ts=80Tu=20 Tv=1,1926 D/H=5Ts=60Tu=20 Tv=0,7937 Temperature losses per day (K) Capacity up to 30 o C (d) l d=210mm,Ts=80Tu=20 Tv=0,40125 D/H=6,75Ts=60Tu=20 Tv=0,27111
Heat storages13 Radiator heating Baseboard heating (tubes) Floor heating Wall radiation heating Floor radiation heating
Heat storages14 92 C 90 C 40 C 36 C 32 C 36 C 32 C 28 C 24 C 20 C
Energy Power Greenhouse 15Heat storages
16 direkt Strahlung ca. 900 W/m² Hohe Energiedichte, Konzentration 20- bis 500-fach Gekühlte Photovoltaik, ETFE-Folie, UV-durchlässig Fresnel-Linse Geringer Materialeinsatz < 10 kg/m² diffuse Strahlung direkte Strahlung Innovative Concentrator UV-transparent, with a light separation effect
17 New methods for long-term storage on glass-fiber storages for cold for heat (horizontally stratified) cold: litres x 4 heat: litres x 9
NEW REQUIREMENTS for STORAGES Heat storages18 Longtherm storage (120 to 150 days) for heating in winter time by sommer heat Optimal heat splitting (till now: slim and high) Minimal losses with maximum storage capacity New insulation systems Relation surface to volume like a sphare Cylinder with High:Diameter = 1:1 Good heat splitting and minimal intern losses (turbulences) New loading systems
Heat storages19 Storages (basic constructions) Unpressurised glassfiber storage (adaptable to different room situations) Low thermal conductivity of glassfiber Double wall principle - "I'm 2 Tanks" Reducing convection losses Curtain Wall multilayer insulation to 20 cm Temperature resistance up to 140 C Locally installation Horizontal layers storage
20Heat storages Temperature losses per day (K) Capacity up to 30 o C (d) storage 400 l, d=100mm,Ts=80Tu=20 Tv=3,514 D/H=5Ts=60Tu=20 Tv=2,313 Temperature losses per day (K) Capacity up to 30 o C (d) l d=100mm,Ts=80Tu=20 Tv=1,1926 D/H=5Ts=60Tu=20 Tv=0,7937 Temperature losses per day (K) Capacity up to 30 o C (d) l d=260mm,Ts=80Tu=20 Tv=0,40125 D/H=6,75Ts=60Tu=20 Tv=0,27111 Temperature losses per day (K) Capacity up to 30 o C (d) l d=110mm,Ts=80Tu=20 Tv=0,32156 D/H=1,2Ts=60Tu=20 Tv=0,21142
Heat storages21 New interior constructions
Heat storages22 Loading profiles Constant temperature Solar profile Step funktion Cloudy profile
Heat storages23 Storage 8 Ideal splitting
THE PERFECT SOLAR THERMAL SYSTEM Heat storages24 High temperature heating circuit Long term heat storage Low temperature heating circuits Fresh water station Highly effective solar collectors Stratified charger Extern heat exchanger
Heat storages25 Installation of cold storage for climate control with „Winter cold“ in summer time
. Haus 11, Wietow, Germany Fon/Fax: +49 (0) / Mail: Internet: Heat storages26