A few years back PV modules (a.k.a. PV panels) meant for domestic use has been limited in choice. The Technology, demand, interest in renewable energy etc all were limited and this in turn limited your choice in selection too. With the petroleum based fuel crises and the renewed interest in limiting the emission of green house gases Newer Technologies were developed.
However the choices for your home PV modules are still limited to only two types. i.e.
- Crystalline Type
- Thin Film Type
Crystalline PV Modules have been in use for some time now. The versatile thin film PV modules are relatively new but offer you a wider application. It is best to bear in mind that these types are not universally suited for all domestic application in every geographical locality.
Place a Thin film Module along side crystalline panel and it will become apparent to that there are some major physical differences for a start.
When you look at the specifications and performance data other major differences also will surface. One might even go to the extent to say that only major common denominator would be perhaps is the conversion of incident solar energy to Electricity!
Crystalline PV Panels
This is the currently most widely used type of Solar Modules. They are available as Single or Multi crystalline PV Panels. One of the reasons why this type is more popular with the House Owners is it’s low capital out lay. Module prices may show a vast difference in favor of Thin Film panels over crystalline modules but in reality in order to obtain the same wattage you would have to spend considerably more for the equipment plus the installation for the former. As a matter of fact about 86% of all PV panels made for terrestrial applications are of this type.
Thin film PV Panels
The term Thin Film Technology covers a vast and diverse lot of second generation PV cells and PV modules. The different module compositions categorized under this classification mainly are:
- Amorphous Silicon ( a-Si )
- Cadmium Telluride ( Cd-Te )
- Copper Indium Gallium Di Selenide ( GIGS )
Of these amorphous Silicon is the commonly used thin film PV panels as these can be easily deposited on glass or plastic (panels or as laminate).This enables it to be produced in varies profiles such as , long continuous rolls, incorporate in to a flexible substrate as a laminate, shingles, or roofing tiles.
a-Si PV Panels are preferred by architects and designers because of its uniform coloration unlike all the others. The sunlight to Electricity conversion efficiency as well as the power density is less. The conversion efficiency is incidentally about 6 to 8% .The surface area for the same power out put is about twice that of Crystalline Modules. Currently US is the largest producer of quality thin film PV modules.
If you consider a small household having a requirement of 3 kw electrical power the equipment cost would be in the region of US $ 32,000 for a thin film PV module installation where as the cost of crystalline PV Modules would be about US $ 25,000.
The extra over installation charges would be about US $ 5,000 for the former while for the latter it would be about US$ 3,500. When you consider a degradation of 0.5% the life span of both types would be 20 years ( 10% degradation) to 30 years ( 15% degradation).
In spite of the high initial cost when you consider the concessions and subsidies available for Micro Generation, Home Energy Saving schemes and the renewable energy targets of the government it is a worthwhile long term investment leading to enhanced property value and a buffer against inevitable future energy price hikes.
Thanks the Techstore Team