21-kW Thin-Film PV Technology Validation -- An NREL/Solar Energy Centre of India MOU Cooperative Project Page: 3 of 5
This article is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided to Digital Library by the UNT Libraries Government Documents Department.
The following text was automatically extracted from the image on this page using optical character recognition software:
21-kW Thin-Film PV Technology Validation-
An NREL/Solar Energy Centre of India MOU Cooperative Project
P.F. McNutt and H.S. Ullal
National Renewable Energy Laboratory
Golden, CO 80401
This paper summarizes findings during a one-week
(27-31 October 2003) site visit to the Thin-Film
Technology Test Bed at India's Solar Energy Centre (SEC)
near New Delhi. The U.S. and Indian governments signed a
Memorandum of Understanding in March 2000 to undertake
a 50-50 cost-shared 21-kW thin-film PV technology
validation project to evaluate the performance of thin-film
photovoltaic (PV) modules under Indian climatic
conditions. This project benefits Indian researchers by
giving them experience with cost-effective PV materials,
and it benefits the United States because data will be sent to
the appropriate U.S. thin-film PV manufacturers for
evaluation and analysis. During the visit, NREL personnel
engaged in technical discussions regarding thin-film PV
technologies with Ministry of Non-Conventional Energy
Sources engineers and scientists. Issues included inspecting
the newly constructed arrays, discussing better methods of
electrically loading the PV arrays, taking I-V traces, and
gathering baseline I-V data.
The purpose of this site visit was for NREL personnel
to meet with SEC researchers to engage in technical
discussions regarding the five thin-film PV arrays installed
at the SEC. Tasks included discussing electrical loading of
the arrays, taking I-V traces during the visit, and gathering
baseline I-V trace data from June 2003. The visit was timed
to coincide with the time of year when the weather is
relatively mild and clear so that taking I-V curves would be
possible. These five thin-film PV arrays were installed at
the SEC to demonstrate that the different technologies
perform well in India's hot, humid, and cloudy climate. The
SEC site is located at 28 35' N, 77 12' E, and at an
elevation of 216 meters. At a 30 tilt in New Delhi, daily
mean global solar radiation values range from 4.8 kWh/n2
(July) to 6.9 kWh/m2 (November). Average monthly
temperatures range from 14C (January) to 33 C (June).
Average monthly rainfall ranges from 3 mm (November) to
200 mm (July) . SEC researchers are gaining operating
experience with the installed PV systems.
2. Technical Approach
Five separate PV systems were installed by Tata BP
Solar India between October and December 2002 (Table 1).
The Rated Power was determined from the name-plate
rating on the deployed modules. The systems are stand-
alone because of utility power quality and connection-
bureaucracy issues. The arrays charge vented Kirloskar
battery banks with 5-kVA AES inverters running various
SEC building electrical loads consisting of lamps, fans, PCs,
air conditioners, TVs, water coolers, data acquisition
systems, etc. All five PV systems became operational May
2003. Baseline IVs were taken June 2003.
The first order of business during the site visit was to
inspect the arrays and system installations. Next, I-V curve
traces were taken. Finally, NREL and SEC researchers
discussed the findings.
Table 1. Overview of SEC PV Arrays
Manu Material Module # of Rated
Modules Power (W)
BP Solarex a-Si MST-43 MV/R 110 4730
dual junction Integra Frame
DunaSolar a-Si DS40-L01-S14 93 3720
First Solar CdTe Universal 102 5100
Siemens CIS ST40 77 2880
Solar narrow frame
Uni-Solar rp Si US-64 56 3584
Total Rated Power=
3. Results and Accomplishments
The biggest problem noted with the installation of the
systems was the array wiring. The installers apparently
lacked the proper tools, parts and training in wiring together
modules, especially those that did not have "traditional"
junction boxes. Otherwise the systems were well installed
and seemed to be operating correctly.
SEC researchers complained that all five arrays were
operating at low (less than 37%) capacity factors. Capacity
factor is defined to be the ratio of an array's actual power
output to its expected output. Because the SEC electrical
loads vary unpredictably during the day, the capacity factor
could not be controlled or determined. The arrays and
systems were performing as expected.
The BP-Solarex MST-43 MV/R dual-junction a-Si
modules have Integra Frames instead of traditional junction
boxes. The installer, lacking instructions in how to wire
these modules, did not properly wire the array.
The DunaSolar glass-on-glass DS40-L01-S14 dual-
junction a-Si modules have no frames and have two leads
suspended from the back instead of junction boxes. The
installer, lacking instructions on how to wire modules, did
not properly wire the array.
Here’s what’s next.
This article can be searched. Note: Results may vary based on the legibility of text within the document.
Tools / Downloads
Get a copy of this page or view the extracted text.
Citing and Sharing
Basic information for referencing this web page. We also provide extended guidance on usage rights, references, copying or embedding.
Reference the current page of this Article.
McNutt, P. F. & Ullal, H. S. 21-kW Thin-Film PV Technology Validation -- An NREL/Solar Energy Centre of India MOU Cooperative Project, article, January 1, 2005; Golden, Colorado. (https://digital.library.unt.edu/ark:/67531/metadc783304/m1/3/: accessed April 25, 2019), University of North Texas Libraries, Digital Library, https://digital.library.unt.edu; crediting UNT Libraries Government Documents Department.