GEAR: Stion Thin-Film Solar Modules

Stion thin-film PV modules
Stion announces their new thin-film PV modules

Stion ( introduced its Elevation Series 3 copper indium gallium selenide (CIGS) thin-film PV modules, available in 140, 145, and 150 W models. Module efficiencies are listed at 13.1%, 13.5% and 14%, respectively. While thin-film modules have historically had low efficiency as a primary drawback, these efficiencies are comparable with crystalline modules that generally range from 12% to about 20%.

Advantages over crystalline include better high- temperature performance (i.e. a lower power temperature coefficient of -0.26% per °C) and less output impact from shade since it is harder to shade the entire cell because it runs the length of the module. Stion modules are available framed (STO model) or frameless (STL model), with glass-on-glass architecture, and are U.S.-made—in California and Mississippi. They are low amperage, high voltage modules (open-circuit voltage (Voc) is around 80 volts), so fewer modules are allowed in series when using string inverters.

Comments (3)

Justine Sanchez's picture

Hi Richard,
as far as cost goes, you can search them online to see how they compare. I found one online retailer selling Stion modules at prices similar to single and poly crystalline modules (also US-made)…around $1/watt.
Justine Sanchez
Home Power Magazine

Richard S. Gieser's picture

I believe that for most of us the most important "efficiency" number is dollars in, watts out. How about some price comparisons to silicon?
Also of interest is sensitivity to EMP compared to silicon. One nuclear attack strategy getting more discussion lately is to detonate high above the atmosphere to cause destruction of electrical devices while leaving most structures and roads intact. I would like to have my solar electric continue working after such an event.

Ian Woofenden's picture

Hi Richard,

It's a bit confusing to use the word "efficiency" in that way -- I think a better phrase would be "cost effectiveness". "Efficiency" in the PV world is normally used to mean energy (watt-hour) output compared to energy (solar insolation) input. And it is not a terribly crucial number in most cases because it ends up talking about _space_ on the roof or ground.

Price comparisons of upfront cost vs. lifetime output in kilowatt-hours (kWh) would be ideal. A reasonable step in that direction is the common measure of $/W -- installed cost per rated watt of capacity. As an example, larger residential PV systems may be in the range of $3 per rated watt (substantially lower than even 5 years ago). If you are comparing apples to apples -- quality of product, warranty, quality of installation and support -- $/W is a reasonable way to compare systems and technologies.

This doesn't answer all your comments, but perhaps sheds a bit of light on the language and comparison issues.

Ian Woofenden
Home Power senior editor

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