BIG Solar Graz: Solar district heating in the city, 450,000 m² for 20% solar fraction Results of a techno-economic feasibility study Sept. 26 th 2017
Solar Heating Solar Cooling Solar Process Heat Solar District Heating 25 YEARS OF EXPERIENCE IN LARGE SOLAR THERMAL SYSTEMS 220 PLANTS IN 20 COUNTRIES
R&D activities of SOLID 16 research projects (3 international & 13 national) > 50 different partners Special focus on collector performance, seasonal heat storage, absorption heat pumps IEA SHC Task 55 Title: Towards the integration of large SHC systems into DHC networks Exchange platform for current SDH and SDC projects Duration: September 2016 August 2020 Contact for joining IEA SHC TASK 55: Operating Agent, Sabine Putz, s.putz@solid.at More information: http://task55.iea-shc.org/
SOLIDs experience in solar district heating in Graz Development from 2002-2017 Contracting Open areas Field test
5 BIG Solar Graz [m²] [Million m³] [MW] 1. Why do we need solar energy? a seasonal pit storage? absorption heat pumps? 2. Dimensioning Solar field Storage Size Heat pumps capacity 3. Sensitivity Analysis + Collector Eff. + Heat Pump Eff. + DH Temperatures
X Why solar energy? Actual situation: Peak load: 530 MW DH demand: 1.200 GWh/a 86 % provided by CHP (gas) Future situation: Delivery contract will end by 2020 Approx. 400 MW necessary Sustainable reliable solution 2020 Quelle: geoland.at Quelle: basemap.at 6
Shares of yearly supply [%] Why solar energy? PLAN for future of DH in Graz Renwable share [%] 7 Condition today Scenario for DH supply in Greater Graz from 2030 onwards Big Solar Graz Industrial waste heat Heatpumps 2030 Mellach generation plant (CHP) solar biomass Sappi (industrial waste heat) heat plant Graz waste heat Helios renewable share other fossil heat pump BigSolarGraz (without driving heat) Source: Grazer Umweltamt & Energie Agentur, Prutsch, Götzhaber, Papousek; Vortrag bei Fernwärmetagen in Velden, 16.3.2016
8 Why big seasonal storage? Monthly demand Energy share > 85 C Energy share > 85 C Flow temperature Return temperature Winter demand Summer demand
9 Why heat pumps? District heating network from the 60ies with high temperatures: flow temperatures -> 115 C return -> 57 C Source: Henrik Lund, 4th Generation District Heating (4GDH)
10 Why heat pumps? Storage temperatures over the year Storage top Storage middle Storage bottom Without heat pump With heat pump
11 Dimensioning BIG Solar Graz Simulation Variationsrechnung Dimensionierung Zusammenhang Kollektorfläche zu Speichervolumina => Wärmegestehungskosten m² m³ 200.000 400.000 600.000 800.000 1.000.000 1.200.000 1.400.000 1.600.000 1.800.000 2.000.000 100.000 150.000 200.000 250.000 300.000 350.000 400.000 450.000 500.000 550.000 600.000 650.000 700.000 750.000 800.000 850.000 900.000 950.000 1.000.000
12 Specifications of Optimal Solution losses Solar coverage: approx. 20 % Total capital expenditures: approx. 200 Mio. EUR
Heat production / load / loss / [MWh/month] 13 Simulated Monthly Generation Shares 450,000 m 2 collectors + 1,800,000 m 3 pit heat storage + 100 MW AHP 200.000 Heat load (w/o summer) Heat losses from pit 150.000 HP driving heat Solar heat via HP 100.000 Solar heat - direct Ind. waste heat 50.000 0 J F M A M J J A S O N D Month in 2 nd simulation year
Required Space Airport Solar Motorway junction Comparison to other infrastructure areas in Graz Big Solar concept ~ 100 ha Required solar system area < 0,8 % of the city area Airport Graz ~ 300 ha Motorw. junc. Graz West ~ 40 ha Generation plant Mellach ~ 110 ha Needed space for fast growing biomass for same energy ouput factor of 30 Conventional biomass floor space requirement for same energy amount factor of 55 14
Solar yield -10%.. Systemertrag.. +10% increase decrease Relative change in solar yield 15 Sensitivity Analysis Sensitivity analysis Zoom of all relatively comparable parameters Temperatures of DH Collector parameters Heat pump parameters Relative parameter change Parameter change -10%.. Parameteränderung... +10% decrease increase
Relative change of solar yield 16 Sensitivity - Network Temperature Sensitivity analysis network temperatures Example: Reduction return 57 C 55 C Parameter change [K] increase in solar yield: 2.8 % 6.860 MWh/year increase in profit (at 35 /MWh): 240.000 /year 4th Generation, return flow 47 C increase in profit (at 35 /MWh): ~ 1 Mio /year Further increase of renewable share!
18 Current Steps According to Utility Acquisition of land Further development of the system concept: Strategy for operation and control Safety aspects Preparation of permissions and administrative procedures Targeted date for completion of approving: Utility presented this summer to public 2nd Quarter 2018
19 Summary Economic competitiveness (despite high network temperatures) geoland.at System solution for available heat at anytime Security of supply Long-term price stability refinancing costs are projectable, independent from the development of prices of fossil energy sources
Future solar-city Graz Unterstützt durch: For further information visit: www.solid.at Erneuerbare Energien 2015-3, Zeitschrift für nachhaltige Energiezukunft, AEE Intec Solarwärme neu gedacht - Fernwärme für Europas Städte http://www.aee.at/aee/index.php?option=com_content&view=article&id=874&itemid=113 Erneuerbare Energien 2016-1 BIG Solar Graz: 500.000 m² Solarkollektoren für 20 % Solaranteil bei Grazer Fernwärme http://www.aee.at/aee/index.php?option=com_content&view=article&id=908&itemid=113 City of Graz Green Future of District Heating in Graz: http://www.grazer-ea.at/cms/aktuelles/idart_2277-content.html Patrick REITER Mail: p.reiter@solid.at S.O.L.I.D. Gesellschaft für Solarinstallation und Design mbh Puchstraße 85, 8020 Graz, Austria 20