Challenges related to mapping Differences between Alpine and urban regions
07.11.2017, G. Goetzl (GBA)
GRETA midterm conference, Salzburg
The GRETA project is co-financed by the European Regional Development Fund through the Interreg Alpine Space programme. Introduction
• Motivation: why talking about mapping in Alpine territory?
• Challenges: are there different requirements on SGE use in Alpine and urban areas?
• Approaches: examples from the projects IIOG-S (Austria), GRETA, GeoPLASMA-CE and WC-33 (Austria)
• Conclusions: are there knowledge gaps to be filled, what should be considered in addition?
2 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Why talking about shallow geothermal use in Alpine territory?
… because it already exists and may play a greater future role….
P90: ~ 560 m a.s.l
P90: ~ 880 m a.s.l
Highest SGE use in Austria (2.291 m above sea level): Restaurant Rifflsee Sunna Alm (Pitztal, Tyrol) DISTRIBUTION FUNCTIONS: Elevation of SGE uses in Austria BHE combined with solarthermal panels) (Source: GRETA project). (Source: https://www.pitztal.com/de/sommer/gastronomie/restaurants- almen-huetten/rifflsee-sunna-alm). 3 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Why talking about shallow geothermal use in Alpine territory?
Spatial distribution of registered SGE uses in Austria (not including license-off uses)
4 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Why talking about shallow geothermal use in Alpine territory?
… and there is an intrinsic knowledge where to apply SGE use ….
… turn intrinsic knowledge into public accessible information and save (failed) investment costs ….
GRETA pilot area Leogang: installed SGE uses in the Leogang valley (elevation: 750 to 900 m. a.s.l).
5 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Are there different requirements on SGE use in Alpine and urban areas?
Mapping parameters
• Transnational maps • Federal state of Salzburg (scale • City of Vienna (scale ≤ 50.000) • Local case studies ~1:200.000) • Potential maps for web based • Potential maps for web based information system information system • Data for energy planning decisions
6 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Are there different requirements on SGE use in Alpine and urban areas?
Mapping parameters
Spatial resolution • Regional (≥ 1:50.000) • Local (≤ 1:50.000) • Consider areas of settlement • Consider small scale units (e.g. urban development areas)
7 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Spatial resolution, Alpine
Surface Geology Salzburg Total area: 7.161 km²
8 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Spatial resolution, Alpine
Surface Geology Salzburg …map based visualization Total area: 7.161 km² problematical…
Filtered by the area of permanent settling Intersected area: 1.297 km² (18,1%)
… why mapping potentials in areas where nobody lives?….
9 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Spatial resolution, Urban
Pilot area Vienna (districts 21 +22) Total area: 69,9 km²
Area of interest Podhagskygasse: 1,6 km² Smallest spatial unit: land property
… influences of local constraints: existing uses, contaminations, installations, land property….
10 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Are there different requirements on SGE use in Alpine and urban areas?
Mapping parameters
Geological, hydrogeological • Surface outcrops, lack of borehole • Borehole data (shallow depths) background data data • Low density of GW data • Low density of GW data • Raster based resource mapping • Data gaps • Vector based resource mapping Borehole data 0,5 /km² • < 30m: 25,3 /km² • ≥ 30m: 5.6 /km² • ≥ 100m: 0,8 /km² • ≥ 200m: 0,4 /km
Groundwater observation wells 0,3 /km²* (14% of all zones) 1,3 /km²* 11 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Mapping strategy, Alpine
Vector based approach Potential mapping groundwater heat pump use
438 hydrostratigraphic units
Statistical averaging of data per unit (P10, P50, P90) No-data areas allowed
… emphasize has to be put on definition of hydro-stratigraphic units….
Too big: levelling effects
Too small: masking effects
Project IIOG-S: number of groundwater temperature observation points wells per hydro-stratigraphic unit 12 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Mapping strategy, urban Vector based approach vs. raster approach Mapping of thermal conductivity
Project WC-31: First TC map of Vienna (2014) 13 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Mapping strategy, urban Vector based approach vs. raster approach Mapping of thermal conductivity Non saturated zone estimated Hybrid map (vector + raster)
…reduce leveling effects by calculating grids and combine with polygon approach in case of insufficient data density….
14 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Project WC-33: Updated thermal conductivity map (2017) Are there different requirements on SGE use in Alpine and urban areas?
Mapping parameters
Subsurface temperatures (soil, • Greater elevation differences • Lower elevation differences groundwater) • Topographic relief (solar radiation • Anthropogenic influence of urban balance) infrastructure • Recharge area of groundwater bodies
15 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Subsurface temperature mapping in Alpine environment
Groundwater temperature Correlation to elevation
Example Lofer (Saalach valley, 630m)
Example St. Magarethen (Mur valley, 1030m)
16 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Subsurface temperature mapping in Alpine environment
Groundwater temperature Correlation to elevation
…greater dependency on elevation of recharge area levels average….
…amplitude controlled by hydrogeology of recharge area (regional hydraulic conductivity….
17 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Subsurface temperature mapping in Alpine environment
Groundwater temperature
Correlation to elevation (recharge area, elevation of groundwater body to a minor degree)
Correlation to hydraulic conductivity of recharge area
Superimposed by local effects (geogenic, anthropogenic)
18 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Subsurface temperature mapping in Alpine environment
Subsurface temperature Correlation with elevation of site
19 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Subsurface temperature mapping in Alpine environment
Subsurface temperature Correlation with elevation of site Influence of slope orientation
20 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Subsurface temperature mapping in Alpine environment
Subsurface temperature Correlation with elevation of site Influence of slope orientation
…the slope orientation (solar energy balance) is controlling the soil temperature….
Valley (750m) S-slope (1.250m)
N-slope (1.450m)
21 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Subsurface temperature mapping urban regions
Groundwater temperature Strong influence of local installations (GW-HP, installations)
Soil temperature Long-term transient signal through sealing of surface and installations
…elimination of thermal gradient in depth >50m and raise of mean surface temperature….
22 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Are there different requirements on SGE use in Alpine and urban areas?
Mapping parameters
Conflict mapping • Higher priority of geogene factors • Higher priority of anthropogenic (e.g. Karst, swell-able rocks, factors (thermal pollution, landslides etc.) chemical pollution, barriers) • Third dimension is essential • Third dimension is essential (extrapolation of surface geology) (installations, lines etc.)
23 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Are there different requirements on SGE use in Alpine and urban areas?
Mapping parameters
Resource estimation • Open loop systems: Calculation • Open loop systems: Calculation of capacities of energy contents in place • Closed loop systems: TC models • Closed loop systems: TC models based on 3D model, validation based on borehole data, validation
24 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Resource mapping in Alpine environment
Workflow
…separate potential into sub-potentials (“productivities”) to reduce no data areas…. …consider permitted yields (intrinsic knowledge)….
…focus on capacities is sufficient in most cases….
25 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Resource mapping in urban areas
Workflow BHE …consider long term transient signals….
GW heat pumps …estimating of capacities is not enough, go for heat in place available…. 퐶 ∙ 퐴 ∙ 퐺푊푚 ∙ ∆푇 Scenario 1: balanced use 푄 = 퐸 ∙ 푅퐹 = 푉퐴 ∙ 푅퐹 𝑖푛 푀푊ℎ 1 푆푡표푟푎푔푒 3600 …use process models in case 퐸 of high user density…. 푄 = 푠푡표푟푎𝑔푒 + 퐸 + 퐸 Scenario 2: unbalanced use 2 퐿푇 푠푢푟푓푎푐푒 푢푛푑푒푟푔푟표푢푛푑
26 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Resource mapping in urban areas
Workflow BHE …consider long term transient signals….
GW heat pumps …estimating of capacities is not enough, go for heat in place available….
Resource planning map (GW heat pumps) for local scale urban development area Podhagskygasse, Vienna (2017) 27 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Conclusions
…yes, mapping challenges and approaches may differ between Alpine and urban areas…. Challenges and gaps
• Deal with low data density (HC, GWT, boreholes) • Consider anthropogenic influences (temperatures) • Deal with surface relief (in combination with hydrogeological settings) • Define resources for energy planners • Deal with subsurface geology • Spatial resolution of data models • 3D geometry is essential • Shallow geothermal use is often influenced by local settings • Validation of models 28 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Conclusions
General aspects to consider
• Resolution of produced output datasets …consider spatial and numerical discretization….
• Estimation of resources
…planers need energy and Project GeoPLASMA-CE: mastergid with minimum capacity…. resolution = 25m applied for all outputs in the pilot area Vienna
29 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Challenges related to mapping Differences between Alpine and urban regions
Thank you for your attention
See more at www.alpine-space.eu/projects/greta Find us on ______Follow us on ______Send us an email at [email protected] Geothermal potential: GRETA’s experience
Geothermal potential
Definition Thermal power which can sustainably be exchanged by a GSHP with certain characteristics (e.g., BHE length, well number) Criteria • Potential as a function of ground • Potential of the “alone well thermal properties, usage profile, doublet” as a function of plant setup hydrodynamic properties • No interference considered, since extractable/injectable flow rate BHEs operate mainly by • Potential of the “well doublet conduction over a limited space with neighbours” sustainable around them density
31 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Open-loop geothermal potential
Potential of the “alone well doublet”: The “well doublet with neighbours”: - Abstractable flow rate - Abstractable flow rate - (Injectable flow rate) - (Injectable flow rate)
Cuneo plain (~3000 km2) - Thermal plumes Interference! Casasso and Sethi, 2017
Livorno Ferraris (NW Italy) Becchio et al., 2017
Munich plain Bottcher, Zosseder et al, 2017 Urich et al., 2010 32 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Volume flux potential
33 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta Thermal potential
34 07 Nov. 2017 GRETA midterm conference. 07th November 2017, Salzburg. See more at www.alpine-space.eu/projects/greta