Are you Considering setting up a solar park, as a business , to provide electricity to grid and generate revenues ? Do you have plans to setup a roof top solar plant for your house , factory or institution ?Every requirement comes with different policy, procedures, material and questions. Do i need to sign a ppa? is there any subsidy on solar plants and how does it work ? What is the life of a solar panel system? Do I need permissions from local electricity board ?
I have answered these question in a different FAQ section. Here you will find answer to those who have made up their mind to go green with solar. The question that is acknowledged in this article is – which solar panels are right for me ?
Here are some factors to consider before choosing your panels. First thing that comes to most minds is price. However I warn you, lower prices can lead to hassles in long run. Solar panels are meant to work for minimum 25 years or more and any compromise with quality will lead to disastrous results. There are many well established brands in market, each brand provide same wattage panels at different cost based on the quality. Some provide IEC bill of material panels at higher cost and non conformity products at lower cost, others are very stringent about quality and work only IEC bill of materials ( best practices ).Best way to go about it is to go to most transparent solar panel manufacturer, a manufacture who welcome you to visit you to their factory when your panels are manufactured. Keep in mind these most important points
1 Cells – always check cells quality. Cells must be A grade solar cells with no reverse current, scratches and spots. Cells must be fresh ( 6 months is expiry date ). Cells must have silver coating and 200 microns thickness or more. Major manufacturer of cells is china. China cells has many quality a , b , c , l grade. There are different technologies available based on cell efficiency , technology and structure. Mono , multi , perc , mwt etc. If panels are respiratory system of solar plant then cells are heart of solar panel so no compromise in this department. Rule of thumb , go for taiwan cells. Some good cell companies are motech, nsp, Mhe
2 Backsheet – Tedlar based backsheets are proven to work for more than 25 years. Tedlar is a registered trade mark of dupont , which in collaboration with NASA formed Tedlar for solar panel used in satellites. Tedlar based back sheets comes in combination with pet as tpt , tpe. It is poly vinyl fluoride. Many manufactures use pvdf , pet , Kpe and other materials but these may not work for 25 years. Please click on link for detailed presentation on solar panel performance comparison based on backsheet.
3 Eva – stands for ethyl vinyl acetate. It is encapsulation for solar cells circuit and one of the most critical component to ensure anti pid panels. Main component used to manufacture Eva is resin and solution. Very few companies use Samsung resin, which is best material. Companies like 3m and Str have very good Eva.
4 Silicon Sealant – A good silicon sealant is crucial to maintain adhesion strength of junction box and frame. A good sealant keeps module safe from rain, winds , dust and harsh environmental factors. Some good solar grade sealants comes from companies like Dow Corning , tonsan , Mccoy etc. Just remember to check sealant because many companies are using tape, which provide no protection.
5 Junction box – is an assembly of diodes, PPO material case and metal rails. jbox is a device used for connecting positive and negative terminals of solar panels. Bypass diodes are used to protect the devices from reverse currents and shading effect. Diodes used in 3 terminal 4 rails diodes starts from 15 amperes and goes upto 25 amperes. Higher the better. Check ip rating of junction boxes based on usage – Ip65, ip67 and ip68. Water protecting is most important for successful solar power plant. Junction box comes with wires and mc4 connectors for joining multiple solar panels. Dc Wires must be 4 mm as per iec standard and best mc4 connectors are most advance water proof ip68
Apart from above mentioned bill of material , other raw material are equally important. Make sure you check each manufactures bill of material from quality of snpb Ratio in Ribbon to AR coating of glass. Frames must be minimum 35 mm width with 20 micron anodised frame.