1. Grid – Tied / On – Grid System
    Grid – Tied / On – Grid Photovoltaic Power System is electricity generating solar PV power system that is connected to the utility grid. Solar power is the primary source of electricity in such a system. This system works in conjunction with the conventional grid.
  2. Off – Grid System
    Off – Grid Photovoltaic Power System is electricity generating solar PV power system that is not connected to the utility grid. The generated energy is stored in Battery packs for future utilization. This system works independent of the conventional grid.
Grid – Tied / On – Grid Systems are mostly preferred due to lower costs and maintenance. This system works efficiently with net metering or when you have high day time power consumption. Whereas Off – Grid Systems can be used universally for any applications but involve higher upfront costs and maintenance.
Solar Panels, Mounting Structures, Inverter, Protection & Isolation Devices, Connecting Cables, Battery Packs (for Off – Grid) etc are some of the primary components of a Solar Power System.
Grid – Tied / On – Grid Systems will automatically shut itself off within a few milliseconds of a blackout to prevent back feeding into the grid. It’s a safety mechanism which shuts off solar power generation till the period of blackout.
Solar Power Systems need sunlight to product power, hence they don’t work in the night. In low lighting conditions like rains, fog etc the efficiency of solar power production drops substantially. Hence we consider 300 sunny days in a year as a thumb rule for annual solar power production in India.
If placed on a flat roof then 1KW of Solar Power System take up approximately 8-10 sq. mt. of space. The location selected for installation should be shadow free.
As India lies in the Northern Hemisphere; the sun is always in the southern half of the sky. Hence Solar Panels are placed facing south at an angle between 0 – 25˚ on a case to case basis.
Solar Panel Efficiency is the ratio of Power of the Solar Panel (KW) to its Size (m2), expressed as a percentage. Lower efficiency Solar Panels occupy greater space and provide lower power output than higher efficiency Solar Panels for the same rooftop size.
The Inverter displays the cumulative energy produced by the solar array. It also comes with a remote monitoring facility which facilitates easy tracking and analysis.
Yes, additional Solar Panels can be added in the array at any time to increase the power generating capability of the system but such an upgrade might need a bigger capacity Inverter.
If the Grid – Tied / On – Grid System is producing excess/surplus power, then its pushed back into the grid and fed to other users. The Net Meter Policy is a billing mechanism that credits the end user for feeding such excess power to the grid. Maharashtra has recently adopted the Net Meter Policy and set guidelines to avail this benefit.
Solar Energy is a clean and renewable energy source. India has 300 annual sunny days which provide for effective and optimum utilization of Solar Energy to fulfil its growing power needs. Solar Power System is a onetime investment with a minimum 25 years life span; it insulates against the rising utility tariff for the longest period. The overall cost of the Solar Power System has substantially reduced due to technological advances and government programs, making Solar Energy more lucrative, beneficial and sustainable source of clean energy.
Some of the benefits provided by the government for Solar Power Plants are:
  • 30% Government Subsidy
  • 80% Accelerated Depreciation in Income Tax
  • Customs Duty & Excise Duty Exemptions
  • 10 Years Tax Holiday on Income from Solar Power generation
  • Net Meter Policy
  • Bank Finance/Loans
1 KW Solar Power System generates 1500-1600 units of electricity per year. Assuming your power cost at Rs. 10 per unit, Solar Power Systems help save up to Rs. 16,000/- on the power bills per year. Pay back period of Solar Power System is usually 3 – 4 years for 25 – 40 years life span.
Performance warranty of 25 to 27 years and manufacturing warranty of 10 years is provided by the panel manufacturer, whereas On-Grid Inverters come with 5 years performance warranty. Installation is warranted for an year.
Grid – Tied / On – Grid Systems are maintenance free whereas Off – Grid Systems require some amount of maintenance in terms of Battery checks. For optimal performance, weekly cleaning of Solar Panels is recommended to avoid bird droppings and other dust.