Tucson Solar Test Yard

Nicholas DavidsonAnd

Ryan PriceUnder the

Supervision ofDr. Alex CroninWith help from Daniel Cormode

And Vincent LonjiUniversity of

Arizona Department of

Physics

Project Background Information

• Facility is property of Tucson Electric Power

• Most Equipment Approximately 5 years old

• Dr. Cronin took over the research at the yard Fall 08

• First data collected November 13, 2008

• Financial support provided by TEP, the Arizona Research Institute for Solar Energy (AzRISE), and the National Renewable Energy Laboratory (NREL).

Project Goals• Short Term:

– Install equipment to monitor:• DC Voltage and Current• AC Power• Temperature

• Long Term:– PV performance (efficiency) in Tucson– Effect of variables such as temperature and

fill factor– Test new PV technologies

Equipment / PV Panel Types• 22 PV (Photo Voltaic) Strings

– Approximately 600 panels– 10 Manufacturers (BP, Sanyo, Shell, Global Solar)– Approximately 90 kWpeak power to grid

– Total cost

• 9 Inverter Types– Xantrex, Fronius, Beacon Power

• Each String has a DC sensors box and AC power meter

PV Panels

Inverter

ACMete

r

Sample PV String

To Grid

4 Primary PV TechnologiesMaterial: Polycrystalline SiliconEfficiency: 14.1%Cost: ~ $4 / Watt

Material: Thin Film SiliconEfficiency: 11.1%Cost: ~ $ 3 / Watt

Material: CIGS (Copper Indium Gallium Selenide)Efficiency: 5.8% Cost: ~ $ 3 / WattMade in Tucson, Arizona

Material: Monocrystalline SiliconEfficiency: 15.6%Cost: ~ $ 5 / Watt

PV Panels

Inverter

ACMete

r

Sample PV String

To Grid

DC Sensors Box

DC Sensors Box

Hall Probe

Input from Panels

Voltage Divider

Output to Inverter and Data Logger

PV Panels

Inverter

ACMete

r

Sample PV String

To Grid

DC Sensors Box

Data Acquisition System

Data Acquisition• AC Power Meter

– Special cards installed in each AC meter– Record 60 “clicks” for each kW AC to grid

• Temperature– Thermocouple for each string

• Data Loggers– Continuously monitor each of the sensor

devices– Local Network– Web Interface

Calibration and Data Analysis• Each string calibrated separately• Data collected every second

– Averaged every minute– Eliminates system noise – Makes data files more manageable

DC Voltage April 26, 2009

DC Current April 26, 2009

DC Power April 26, 2009

AC and DC Power Comparison

Inverter Efficiencies April 26, 2009

0.12

0.10

0.08

0.06

0.04

0.02

0.00

AC

Pow

er /

Lig

ht P

ower

5040302010Panel Temperature (C)

Sharp Panels & Aurora inverter(rated 14 %)

Unisolar Panels & Fronius Inverter(rated 7 %)

Occurance

Acknowledgments• UA Physics

– Dr. Alex Cronin– Daniel Cormode– Vincent Lonji– Ryan Price

• UA Optics– Ray Kostuk– Brian Myer

• UA Atmospheric Science– Bill Conant

• AzRISE• TEP

– Bill Henry

Thank You!