Thin film solar PV cell panels are now being marketed in Ireland by reputed renewable energy promoters. A recent innovation, thin film solar cells are technologically different in their production while being chemical different to the traditional Mono crystalline or Polycrystalline silicon PV panels.

What are thin film solar modules?

A thin film solar module is made up of thin film solar cells (TFSC).The cell itself may be made by depositing ( by a process known as chemical vapour deposition) one or more fine layers of Photo Voltaic material on a substratum using modern technology. The substratum may be glass, plastic or metal. The thickness may vary from a few nanometres to several micrometres.

They are categorized according to the PV material used in them. As opposed to the conventional PV cell material of crystalline silicon, thin film PV cells use amorphous silicon or other thin film silicon, cadmium telluride, copper indium gallium selenide, all of which are causing a revolution in the solar power generation and sustainable building architecture.

The crystalline silicon conventional modules can reach efficiencies up to 20% in domestic applications.

The efficiency in current commercial thin film modules is less in comparison (TFSC i.e. the cell) having up to 20% while the production modules reaching only about 9 %). But in all likelihood soon TFSC modules might catch up with the established conventional panels in that aspect, due to the hectic R & D now on.

However one thing is certain. The world price of silicon material is increasing in leaps and bounds due to the heavy demand by mass producers of crystalline silicon PV modules. And if the industry and the consumer needs low prices they’ve got to look where less material is needed and where the mass production techniques lowers the prices. In this respect TFSC modules future seems to be the most secure.

Currently the problem seems to be the inability of the manufacturers to meet the demand world over.

Problems associated with conventional modules and how TFSC may be an answer

As we all are aware, PV modules present a nightmare for architects, structural engineers and designers, when installed on roof top or even at ground level. The strict requirement of southerly orientation, problems associated with shaded or low sunlight areas when the panels are installed some times in these locations are not the least. The cost of tracking systems too is prohibitive in small capacity applications.

The thin film PV panels provide you with a flexible solution for all these complications.

• They are thin composites.

• They have only a thin film of PV material coated on substrata of plastic, glass, thin metal sheet etc. and are easy to handle.

• The substratum itself could be any rigid and smooth material and not necessarily glass and less prone to damage.

• The solar PV material is totally unlike mono or poly crystalline silicon panels in that they can withstand higher temperatures.

• The thin film panels are much lighter due to their reduced dimensions and less material used.

• The efficiency is not high as in the conventional, but it is compensated by the low price (even in this initial stage) and the ability to cover a larger area easily.

• On flat roofs as well as pitched roofs the output is unaffected due to vast areas covered.