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The importance of the design phase in Energy Quality Management: an example of the application of the parametric analysisMarco Molinari, Ph.D.Department of Automatic Control, KTH1

KTH ROYAL INSTITUTEOF TECHNOLOGYOutlineBackgroundEnergy efficiency targets in the built environmentTools for analysis: S.E.P.E.S.E.P.E.in practice: performance improvement with exergy analysisGSHP improvement through integrated design Current research Conclusions

2Energy use in the world: the need for reduced and more sustainable energy useSource: IEA 2010Source: IEA 2011387%32%No wonder that EU prioritizes reduction of energy use in buildings in its energy policy3Energy and exergy efficiency4

Source: Mure Odyssey databaseSource: Fraunhofer IBPEnergy supply type in buildingsCan we improve our energy management by means of exergy concepts?Energy quality (exergy) mismatch between supply and demand indicates potential for energy management improvements

Main hindrances:Lack of a shared understanding of the advantages of the exergy approachNo standardized exergy analysis calculation tools availableNeed for demonstration projects

5Examples of available exergy analysis software programs: IEA ECBCS Annex 49Human Body Exergy CalculationCascadia An Exergetic Approach to Neighbourhood DesignPre-Design Tool for buildings exergy analysisDPV ToolS.E.P.E. Software for Exergy Performance Assessment6What we mean with exergy analysisNo commercial software programs available too specific field

6S.E.P.E. HVAC components

7GeneratorsHPs, chillersboilerssolar collectorsDHHeat exchangers

Distribution components Ducts/pipes Fans and pumpsEmission systemsradiatorsFH air unitscontrollersSimplified building envelopeComponent example: boiler8

8Example of S.E.P.E. HVAC system assembly 9

9Improvement of heat pumps COP performance with S.E.P.E.10Reservoir T0ReservoirT1Reservoir T2Floor Heating SystemDHWHeat Exchanger 2Heat Exchanger 3P2Heat Pump 2P1Heat Pump 1T4T5T7T8T6T10T9T11= 55T12= 10CT3Tset= 22CHeat Exchanger 1

Complex systemFor a defined energy (exergy) service (DHW and FH demand) we want to improve the exergy efficiency (i.e. provide less electricity)Example: how much do temperature T1 and heat exchanger area 2 affect the OVERALL performance of the system?Does the reduction of the overall exergy loss induce an increase of the COP? (of course we know that this is true but we want to quantify how much)10Results11The same physical system can achieve different performance if the subsystems are not properly matched

Add information on the variation of the overall exergy loss

Connect points with arrows11How to extend these results to other fields: design of ground source heat pumps

Building heated area: 8000 m2Locations: Stockholm and MadridParametric studyBuilding envelopeWalls and roof insulationBorehole fieldBorehole spacingNumber of boreholes

12http://sustainableenergysystemz.com/the-benefits-of-ground-source-heat-pumps/1679/Boreholes ! Why so many?

Env heat out of the ground : whats the problem? Heat & cost

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Results: Stockholm

Results: Madrid13Multiparameter analysis & optimal configurations13Current research at KTH: advanced control strategies in buildings

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Integration of a model in the controller; optimized control action based on the model predictions based on the forecast of temperature, radiation and occupancy (internal gains) and the current status.

Further development: MPC exergy:Building controlGround storage14ConclusionsConceptual and calculation tools for energy quality management already exist and are now mature enough to shift from research to applicationsThe application of exergy concepts can be highly valuable to the improvement of the design of buildings, especially in connection to parametric analysis Examples of improved design of buildings and buildings components based on exergy principles are needed to show the potential improvements in energy quality managementAdvanced controls schemes and exergy can be an innovative match to further decrease the overall energy used in buildings 15Thank you for your attention!16S.E.P.E. systems components layout

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Maybe replace pic with a video17Exergy VS energy or exergy AND energy?Energy analysis alone has shortcomingsEnergy efficiency does not introduce a unique reference to show how much a system can be improvedWe somehow account for the energy quality through primary energy: but how can we improve the building design without taking into account explicitly exergy?Exergy approach is not a standardized approachExamples of design and implementation on real buildings are limitedIt lacks standard commercial calculation software programs18Average exergy efficiency in built environment is low

18Parametric analysis19