Subcontractor: Dr. Alex Cronin, University of Arizona
NREL Contract 99043, “Study Degradation Rates of Photovoltaic (PV) Modules Deployed in Arizona”
NREL Technical Monitor: Dr. Sarah Kurtz
Description: First Monthly Report
Author: Steve Pulver
Date: June 25, 2009
The data used for this study is expected to be collected from the Tucson Electric Power (TEP) solar yard. The majority of these modules were purchased between 2001 and 2003. There should be data from multiple years, from multiple types of modules.
Summary of what we are capable of measuring at the TEP solar yard:
A.
Types of modules and dates purchased:
PV Make
Sharp
Kyocera
BP Solar
PV Model
NE-Q5E2U
KC150G-A
BP 3150U
SC Type Inverter Make
Date
Purchased px-Si px-Si px-Si
Aurora
Xantrex
Xantrex
Mar-2003
Apr-2003
May-2003
Uni-Solar
Sanyo
BP Solar
Schott ASE
US-64 MJ-Si Fronius
HIP-G751BA2 HIT (Si)* Sunnyboy
MST50 MVHS MJ-Si
ASE-300-DGF/17 px-Si
Xantrex
Xantrex
BP Solar
Schott ASE
SX140S px-Si
ASE-300-DGF/50 px-Si
Global Solar GSE GG-112, 13309 CIGS
Shell Solar ST40 CIS
Xantrex
Xantrex
Xantrex
Xantrex
Jun-2003
May-2003
Sep 2001?
Jul-2001
2002
Aug-2001
2002
Sep-2003
Sanyo
Shell Solar
BP Solar
BP Solar
AstroPower
Solarex
Evergreen
Schott ASE
HIP-J54BA2
SQ150-PC
HIT (Si)* Fronius x-Si Xantrex
MST50 MVHS MJ-Si
MST50 MVHS MJ-Si
Beacon
Sharp
Jul-2003
Sep-2003
Feb-2004
Sep 2003?
APi-165-MCB
MST-43MV x-Si (?) Xantrex a-Si/a-SiGe Solectria
May-2004
Mar-2000
EC-115-GL unknown Soleil 2000 Sep-2007
300-315 mixed unknown 3-phase unknown
Global Solar GSE Slim-Line 62W CIGS Xantrex 2004
BP Solar BP4170S x-Si Xantrex Sep-2006
B.
Historical data:
Peak AC power output of the inverter, sampled at 15 min. intervals. This data should be going back to the time when the units were placed in operation. This information was collected by TEP, and we have been working with them over the last couple of weeks to get access to this data.
C.
Present data
Since the fall of 2008 additional measurements have begun; panel temperature, DC voltage, and DC current, all sampled at 1 second intervals

D.
Future data
Recently a weather station has been added. Data will now include Irradiance measurements, air temperature, wind speed, and wind direction sampled at 1 second intervals.
Recent work
I (Steve Pulver) have been working on the project since June 1, 2009. Most of the time has been spent working at the TEP solar yard, learning about the configuration of the hardware. In that time, the additional weather station has been added, and data collection has begun from this weather station. We will have a second, additional weather station in operation soon. Most of this work was done by other University of Arizona students including Daniel Cormode, Jason
Veatch, and Kevin Pounds under the supervision of Dr. Alex Cronin from the University of
Arizona and Mr. Bill Henry from Tucson Electric Power.
A. A Hall probe (for current measurement) has been added to the battery backup system of one inverter.
B. Attempted calibration of one DC voltage output of one of the units. There was a significant amount of noise in the measurement (with RMS values about the mean of 10% of the mean during a one minute period. We used smaller resistors in the voltage divider and this improved the signal to noise ratio.
C. First weather station was connected to an existing DAS box (Data Acquisition System) and a data logger was programmed to sample data from the weather station. An additional DAS box has been built for the second weather station and
Plans for the coming month
A.
verify calibration on our measurements: peak DC voltage and current, and panel temperature.
B.
Once we have access to the historical power output data, calculate total energy output by year.
C.
Find historical solar irradiance data that can be correlated with our TEP power data.
D.
A visit to NREL for Steve Pulver, Alex Cronin, and four other University of Arizona researchers has been planned for June 25 and 26.
Any questions can be directed to either Alex Cronin or myself, Steve Pulver.
Steve Pulver stephen_pulver@hotmail.com
520-294-6152 (Home)
Alex Cronin cronin@physics.arizona.edu
520-465-8459 (Cell)