Tunnel Geothermics International experiences on regenerative energy concepts in tunnel projects

Transcription

1 International Symposium on Energy Geotechnics Universitat Politècnica de Catalunya (UPC) Barcelona, Spain. June 2nd to 4th 2015 Tunnel Geothermics International experiences on regenerative energy concepts in tunnel projects Dipl.-Ing. Patrik Buhmann Institute of Geotechnical Engineering, University of Stuttgart IGS Univ.-Prof. Dr.-Ing. habil. Christian Moormann Dr.-Ing. Norbert Pralle Dipl.-Ing. Wolf Friedemann

2 Overview Introduction Test Plants Measuring results Conclusions and outlook Introduction Test plants Measuring results Outlook 2

3 Introduction to tunnel geothermics geothermics Geothermie open systems closed systems heat exchanger HE hydrothermal systems wells tunnel drainages groundwater capture direct use of groundwater Introduction Test plants Measuring results Outlook 3

4 Introduction to tunnel geothermics geothermics Geothermie deep geothermics > 400 m Oberflächennahe shallow geothermics Geothermie < 400 m BHE evaporator probe surface collector hybrid Hybridsysteme systems energy piles diaphragm walls anchors Hybrid-Misch- duo-hybridsystems Systeme base slabs subsoil transportation tubes tunnel-absorber Introduction Test plants Measuring results Outlook 4

5 Basic sketch subsoil tunnel tunnelgeothermal plant (cooling mode) geothermal plant (heating mode) tunnelthermal plant (cooling mode) Duo-Hybrid-System Introduction Test plants Measuring results Outlook 5

6 External actions / interactions use of groundwater meteorology atmosphere topography temperature development surface sealing soil cover anthropogenic heat flux absorber system hydrogeology tunnel length road tunnel railway tunnel subsoil conditions excavation damage zone (EDZ) geothermal heat flux Introduction Test plants Measuring results Outlook 6

7 Overview test plants Germany Stuttgart Austria Jenbach Introduction Test plants Measuring results Outlook 7

8 General data Stuttgart Jenbach double tracked 380 m metro tunnel excavated section 72 m² mined tunnel with inner and outer shotcrete lining double tracked 3470 m railway tunnel excavated section 134 m² mechanical tunnel drive with tubbing support 800 m absorber pipes Ø 25 mm 360 m² geothermal activated area 2 x 10 m geothermal activated section 4700 m absorber pipes Ø 25 mm 2200 m² geothermal activated area 54 m geothermal activated section Introduction Test plants Measuring results Outlook 8

9 Monitoring setup Stuttgart Jenbach 6 measuring probes logging the subsoil temperature 8 measurement cross sections logging the lining temperature 8 measuring devices logging the tunnel air temperature 8 measuring devices logging the tunnel lining temperature 2 measuring devices logging the tunnel air temperature Introduction Test plants Measuring results Outlook 9

10 Hydrogeological conditions Stuttgart Jenbach Introduction Test plants Measuring results Outlook 10

11 Overview of operation temperature [C ] 25 cooling mode heating mode cooling mode no gethermal operation out of operation no gethermal operation heating mode Stuttgart 1200 flow rate [l/h] outlet temperature inlet temperature flow rate / / / / / / / / /2015 Introduction Test plants Measuring results Outlook 11

12 Cooling mode 2012 temperature [ C] flow rate V~560 l/h V~1085 l/h flow rate V [l/h] 1200 Stuttgart extraction capacity Q [W/m²] ϑ inlet temperature outlet temperature tunnel air temperature extraction capacity flow rate 04/ / / / / / / Introduction Test plants Measuring results Outlook 12

13 Subsoil temperature development Stuttgart overlapping ϑ OF + ϑ TL influence depth app. 7,0 m influence of geothermal operation tunnel air inlet temp. ϑ TL outlet temp. [ C] Introduction Test plants Measuring results Outlook 13

14 Conclusions and outlook Conclusions heat extraction rate of Stuttgart is highly influenced by the tunnel air extractions rates up to 50 W/m² and more are achievable development of simulation tools development of design and operation recommendations Outlook knowledge transfer to other subsoil constructions investigations on the seasonal heat storage capability development of the interface point between the building and the subsoil equipment Introduction Test plants Measuring results Outlook 14

15 Construction of interface point docking construction connection tube absorber pipes construction joint outer lining inner lining Thank you for your attention! Funded by: Cooperation: Institut für GebäudeEnergetik Introduction Test plants Measuring results Outlook 15