120kW Solar Plant Price list and Major Components
Major components in a 120kW Solar Plant
Solar PV Panels are the most important part of any rooftop solar system. There are various variations in technology and make of the panels available, thus it is crucial to choose wisely according to the requirement. Solar Panels are mostly warrantied for 25 years (performance warranty) and have a useful life of about 30 years.
Panasonic, Trina, Canadian Solar are a few very excellent brands you can opt for. In Indian brands, Vikram, Waaree and Renewsys rule the market.
For a 120kW Solar Plant about 348 qty of poly solar panels of 345wp would be required or 240 qty of mon-perc solar panels of 500wp. For poly, Vikram / Renewsys Solar are reputable Indian brands which offer quality product at reasonable price. Trina Solar, Panasonic or Canadian solar well known brands to choose which have high generation capability even in case of low light conditions.
Solar inverters are the heart of the system. They basically convert the DC power generated by the solar panels and give AC output which is used for running our loads. They are also connected to the internet so that the energy generated by them is logged and displayed over the app.
String inverters of brands Growatt, Solis, Sofar and Delta are prominent in the market in India. For a more premium technology and service, Solaredge inverters with module level optimisers can be considered.
For 120kW Solar Plant, single phase inverters by Solis or Sofar / Growatt are excellent pick. For a more premium segment, SMA / Sungrow offers good reliability along with customer service.
Cables and Junction Boxes (DCDB and ACDB)
In any solar plant the third most important component after Solar Panels and Solar Inverter is the Junction boxes along with the cables used. DCDB or AJB is used to monitor and isolate, if need be, the solar inverter in case of any fault. Another important function of DCDB is to combine the strings from solar panels according to the Volt-Amp configuration as per the solar inverter input values. ACDB is used to majorly monitor the output from the Solar Inverter and isolate, if need be, the connected loads in case of any faults. Another combiner box is sometimes used to combine outputs in case more than one solar inverter is used.
Cables in solar plant are of two types, DC cable and AC cable. As the name suggests, DC cables are used on the DC side of the solar plant, that is inverter and to connect the solar panels to the DCDB and then finally to the solar inverter. AC cables are used to connect the output from solar inverter to the acdb and then finnaly to the loads. AC cables are also of two diffrent types, single phase and three phase, according to the Solar inverter type. Mostly, Solar Plants above 6kW are three phase and below 6kW, single phase.
For 120kW Solar Plant the junction boxes should consist of a MCB (Over ampere protection) and a SPD (Over voltage protection) in both the junction boxes. For AC cable of diameter, accurate calculations must be made according to the inverter / inverters used and the distance from the inverter output to the distribution box
Earthings and BoS
All solar plants are earthed for AC side, DC side and Lighting strikes to earth the excess current which may flow into the system and prevent electrocution. There are many cheaper diffrent variants of earthing available in the market, but 20mm diameter and 2 meter long copper bonded electrode is the one you should opt for.
BoS or Balance of System consists of all the accessories like solar plant structure, thimbles or lugs, ferrules, MC4 connectors, saddles, etc. Solar structure for rooftop and ground mounted plants is diffrent with diffrent installation procedure. Solar structure is further classified for rooftop solar plants according to the roof type.
For a 120kW Solar Plant, 2qty copper lighting arrestor along with 5 qty of earthing (2 X AC, 2 X DC and lighting arrestor) are recommended.
Price list for a 120kW Solar Plant
Rs28.8 / watt
Rs7.5 / watt
Cables and Junction Boxes
Rs3.5 / watt
Earthing and BoS + Accesories
Rs7 / watt
Total Solar Plant Kit
INR 46.8 / watt (INR 5616000)
+ applicable GST