Sustainable Energy at Georgia Tech Aquatic Center

1. The Georgia Tech Aquatic Center Georgia Institute of Technology

2. + D E F G A B C 6N N 5N 4N 3N 2N 1N 1S 2S 3S 4S 5S 6S 7S 8S 9S + 10S - 15S “string” = 12 modules in series 20S 25S - 28S

3. Section 1 Section 1 Section 1 2 2 2 Section 2 Section 2 Section 2 1 Section 3 Section 3 Section 3 String 19S String 19S String 19S String 20S String 20S String 20S Section 4 Section 4 Section 4 String 27S String 27S String 27S String 28S String 28S Column A Column G String 28S Column F PV array dc current collection on the Aquatic Center roof 3 }Columns B, C, D, E 7 feeders down to main dc combiner .... 1 1

4. Block diagram of the Aquatic Center Power Conditioning System Unfiltered ac Filtered ac 750 V dc to isola- tion trans- former dc-dc boost stage IGBT inverter bridge ac line filter PV array Output power, tempera- ture, other status signals Boost stage con- troller Inverter bridge controller dc link voltage Grid voltage/ frequency array dc power Max power tracking dc-ac inversion

5. Method of mounting PV modules to Aquatic Center roof PV MODULE ARRAY HEIGHT RIGID INSULATION STANDING SEAM ROOF MOISTURE BARRIER 1/2" LOADMASTER CORRUGATED METAL DECK STEEL TRUSS STRUCTURE

6. to: interactive displays remote computers etc. Rooftop data inputs: Global horizontal irradiation Plane-of-array global irradiation Array temperature (x 9) Wind speed } CR-10 UPS MD-9 DC-112 modem 110 Vac Rooftop DAS MD-9 Inverter room data inputs: dc string current (x 4) Array dc voltage Real and reactive 3-phase ac power Inverter status (x 6) } Data com- munications system CR-10 UPS MD-9 110 Vac Aquatic Center PV System Data Acquisition System Inverter room DAS

7. Rooftop weather station Georgia Institute of Technology

8. Measured AC power production: February 2001

9. Measured POA insolation: February 2001

10. Total efficiency of the GTAC PV system: February 2001

11. Predicted power output of the Aquatic Center PV array using PVFORM/TMY Effects included: 14% total dc-side losses (dust, conductors) north-facing modules

12. Average system efficiency of the GTAC PV system

13. Cumulative AC energy production of GTAC PV system (1997)

14. Cumulative AC energy production of GTAC PV system (1998)

15. Cumulative AC energy production of GTAC PV system (1999)

16. Cumulative AC energy production of GTAC PV system (2000)

17. Cumulative AC energy production of GTAC PV system

18. The SAC Canopy AC array Georgia Institute of Technology

19. PV system design: the AC array .... ac line/bus (grid) .... Each PV module has its own PCU; no dc-side series-parallel connection of modules; parallel ac connection. Georgia Institute of Technology

20. Predicted power output of the SAC canopy AC PV array

21. PV Systems research at GT • Monitoring of GTAC PV system • Verification of PV systems models and design • procedures • Parameter estimation and measurement • Monthly reports available on the WWW (public • education and awareness) • URL: http://www.ece.gatech.edu/research/UCEP/PVSystems • PV system power electronics • Islanding prevention • Module-integrated maximum power point • tracking • Distributed generation Georgia Institute of Technology