1. THE DISTRICT COOLING NETWORK THAT OUTPERFORMS NATURALLY PAGE ENERGY IS OUR FUTURE, WE MUST SAVE IT! EEMOD’S Nantes – 15 / 09 / 2009 > Overall chiller system energy efficiency 1 Sénéjean B, Merchat M, Faurel C, Thibault S, Doucouré A, Benassis F

2. THE DISTRICT COOLING NETWORK THAT OUTPERFORMS NATURALLY PAGE ENERGY IS OUR FUTURE, WE MUST SAVE IT! EEMOD’S Nantes – 15 / 09 / 2009 > Introduction > 2 A growing demand for air-conditioning EE stakes in chilled water production: Controlling the energy consumed by existing systems Developing ever more energy efficient systems Accordingly, the need to know the true performance of chiller systems How do we assess the energy efficiency of chilled water Installations?

3. THE DISTRICT COOLING NETWORK THAT OUTPERFORMS NATURALLY PAGE ENERGY IS OUR FUTURE, WE MUST SAVE IT! EEMOD’S Nantes – 15 / 09 / 2009 > Indicators > 3 Nominal COP and EER :energy efficiency indicators established by the main installation manufacturer for nominal working conditions ESEER and SEER : energy efficiency indicators taking part- loading operations into consideration COP and EER quantified : energy efficiency indicators established as part of this study taking into account the true performances of the installation and its accessories N.B. The only difference between EER and COP is the units used EER: btu.hr -1.W -1 COP/ESEER: Wf/We

4. THE DISTRICT COOLING NETWORK THAT OUTPERFORMS NATURALLY PAGE ENERGY IS OUR FUTURE, WE MUST SAVE IT! EEMOD’S Nantes – 15 / 09 / 2009 > Measurement equipments : 31 Temperature sensors 12 Wattmeters

5. THE DISTRICT COOLING NETWORK THAT OUTPERFORMS NATURALLY PAGE ENERGY IS OUR FUTURE, WE MUST SAVE IT! EEMOD’S Nantes – 15 / 09 / 2009 > Specifications for the units selected 5 BuildingStartingCompr.Refrig. Cooling System Cooling Power (KW) Outlet evaporator water temperatur e Inlet condenso r water temperat ure A20006 screwR134A 3 cooling towers 12605°C30°C B19956 reciproc.R22 2 cooling towers 9406°C30°C C 19904 pistonR22 2 cooling towers 4846°C30°C D20088 pistonR407C 1 Dry cooler 7767°C25°C The results provided only concern 4 of the 7 plants equipped with instruments

6. THE DISTRICT COOLING NETWORK THAT OUTPERFORMS NATURALLY PAGE ENERGY IS OUR FUTURE, WE MUST SAVE IT! EEMOD’S Nantes – 15 / 09 / 2009 > Quantification methods > 6 Measurements of all electricity consumptions for each appliance Measurements of all heating power exchanged at the condensers and at the evaporators Readings recorded at 10 minute intervals over the entire year The overall energy statement is produced

7. THE DISTRICT COOLING NETWORK THAT OUTPERFORMS NATURALLY PAGE ENERGY IS OUR FUTURE, WE MUST SAVE IT! EEMOD’S Nantes – 15 / 09 / 2009 > Scope of measurements carried out Water condensers Air condensers Performance measurements for all equipment devoted to chilled water production – Does not include distribution 7

8. THE DISTRICT COOLING NETWORK THAT OUTPERFORMS NATURALLY PAGE ENERGY IS OUR FUTURE, WE MUST SAVE IT! EEMOD’S Nantes – 15 / 09 / 2009 > Weekly results > 8 Characterization of true chilled water production plant efficiency

9. THE DISTRICT COOLING NETWORK THAT OUTPERFORMS NATURALLY PAGE ENERGY IS OUR FUTURE, WE MUST SAVE IT! EEMOD’S Nantes – 15 / 09 / 2009 > Example of a fault recorded during operations Control mode modification: BeforeAfter T° average cond. before January = 34°C  COP < 1 T° average conditions after January = 21°C  COP > 1 The operator has no measurement instruments = Plant operation is not optimised 9

10. THE DISTRICT COOLING NETWORK THAT OUTPERFORMS NATURALLY PAGE ENERGY IS OUR FUTURE, WE MUST SAVE IT! EEMOD’S Nantes – 15 / 09 / 2009 > The average loading rate per machine is kept at a very low level = Performances deteriorate Example of a fault recorded during operations 10

11. THE DISTRICT COOLING NETWORK THAT OUTPERFORMS NATURALLY PAGE ENERGY IS OUR FUTURE, WE MUST SAVE IT! EEMOD’S Nantes – 15 / 09 / 2009 > Results – Distribution of units consuming energy 49% of the electricity consumed by the plant investigated is consumed by the accessories 11

12. THE DISTRICT COOLING NETWORK THAT OUTPERFORMS NATURALLY PAGE ENERGY IS OUR FUTURE, WE MUST SAVE IT! EEMOD’S Nantes – 15 / 09 / 2009 > Summary of results > 12 The results reveal major differences between measurements carried out and nominal performance levels

13. THE DISTRICT COOLING NETWORK THAT OUTPERFORMS NATURALLY PAGE ENERGY IS OUR FUTURE, WE MUST SAVE IT! EEMOD’S Nantes – 15 / 09 / 2009 > Conclusions > 13 Few or no measurement instruments on most of the installations True performance levels can only be assessed by carrying out of measurements over sufficiently lengthy periods of time The impact made by the operation cannot be assessed using tests of numerical simulation

14. THE DISTRICT COOLING NETWORK THAT OUTPERFORMS NATURALLY PAGE ENERGY IS OUR FUTURE, WE MUST SAVE IT! EEMOD’S Nantes – 15 / 09 / 2009 > Outlook > 14 Measurements Measures should be carried out on a wider sample of installations Equipment The need for specific meters for recording energy consumption and chiller energy produced by the installations Assessments and comparisons of the various technical solutions of the retrofit impact on installations involving HCFC of stand-alone installations and of centralised installations