Thin Film Solar (Amorphous Solar)
Why would anyone want to invest in a product that offers half the performance in efficiency when for just a little more money you can purchase a much higher efficiency product. The discussion here pertains to thin film solar products versus crystalline solar products on residential roof tops. Year after year companies have come and gone that have tried to successfully commercialize thin film solar panels in the U.S. market. Many of those companies failed, leaving their customers with unenforceable warrantees.
In light of the developing market for solar, several companies are once again attempting to make thin film meet up to its promises of lower priced solar but at what cost.
Well for one, efficiency. Most of the thin film solar products on the market today offer efficiency ratings that are almost embarrassing when compared to conventional crystalline solar products. Try 6.3% versus 13 to 14 % for one of the more popular thin film solar panels that are being offered on today's market. If this reduced efficiency was reflected in the true cost to the consumer then thin film might be something to consider, but for residential applications ?
Consider the following:
1. Because of thin film's low efficiency ratings a thin film solar panel is approximately twice the size of a typical crystalline solar panel. Here's a graphic that was drawn to scale in Photoshop which illustrates the difference in size of a 60 Watt thin film (Amorphous) solar panel shown in purple versus a 60 Watt crystalline solar panel shown in yellow. Note how much space the less efficient thin film solar panel uses.
2. This increase in size obviously translates into increased weight. So the load that is applied to a residential rooftop is greatly increased. For example a 1,920 Watt solar system consisting of thirty two of the 60 watt thin film solar panels referenced above weigh approximately 985.6 pounds whereas a high efficiency mono-crystalline system using only twelve 170 watt solar panels with an output of 2,040 watts weighs in at only 422.40 pounds. That's almost a half a ton on the roof of your home when installing a relatively small solar system consisting of thin film solar panels and we haven't even considered the added weight of the metal mounting racks that support the solar panels.
3. Increased weight means increased shipping costs for the same distance that the product is shipped, which of course raises your acquisition cost and the products carbon footprint.
4. Along with the increased number of panels that are required, comes Increased labor costs. Remember their are thirty two 60 Watt solar panels in this thin film solar system versus only twelve 170 Watt solar panels in the mono-crystalline solar system.
5. The increased number of solar panels in the thin film solar system means that a much larger metal mounting structure will be required to attach the panels to your roof which translates into a larger number of holes that will be needed to be drilled into your roof to mount the larger mounting structure which may increase the risk of roof leaks.
6. Several new companies that have come on the thin film solar scene are touting their product's reduced impact on the environment, but the CdTe (Cadmium-Telluride) technology that is used in many of these new thin film offerings contain the toxic, heavy metal, Cadmium. Cadmium and cadmium compounds are known to be human carcinogens. Of course direct exposure would be necessary but never the less the toxicity of Cadmium and Cadmium compounds do exist.