Rooftop Solar Power Systems


Rooftop solar installations or Rooftop Solar PV systems on Residential and Commercial sites offer unparalleled energy and revenue generation opportunities. In fact, Residential and Commercial roofs are the most under-utilized assets. Utilizing these assets by installing Solar Power plants can bring in long term benefits.

Apollo Commitment: “Providing Sustainable & Cost-Effective Solar Power Solutions Using Underutilized Rooftops’.

Apollo offers Customized On-grid, Off-gird and Hybrid Solar solutions for Residential and Commercial purposes.

There is a lot of unused rooftop space that is underutilized in the case of large buildings. The rooftop space can be used for efficient energy production by installing Solar panels on the rooftop. This would meet the captive power requirements of the commercial buildings.

Even homes can also have solar rooftops installed to become self sustainable and reduce the dependency on grid electricity.

Salient Features of Rooftop Solutions:

  • Pure Sine Wave Inverter
  • Adjustable battery charging current based on applications
  • Compatible to mains voltage or generator power
  • Auto restart while AC is recovering
  • Smart battery charger design for optimized battery performance
  • Cold Start Function
  • Fulfills power requirements for conventional applications (Light, Fan, TV, Fridge)
  • Generates Power and Supplies even when electricity is there
  • Protects against overload, short circuit, battery discharge / overcharge
  • Easy Installation, Easy Operation and minimal Maintenance
  • Export surplus energy generated to the grid
  • 5 years of System warranty
  • 25 years of Solar module warranty

Applications of Solar Rooftop Solutions:

  • Residential Complexes
  • Villa and Row Houses
  • Office Spaces
  • Industries
  • Schools and Colleges
  • Hostels
  • Hospitals
  • Institutions
  • Eateries & Lodges
  • Places of Worship
  • Covention Centers
  • Farm Houses

Frequently Asked Questions(FAQ)

The main component of the Solar PV system is the Solar PV module/Solar Array.
The rest of the components of the Solar PV system are called Balance of the System(BOS). These
include components like Inverters, Charge Controllers, Battery, Wiring, Mounting systems, switches
and others.

  • Solar Module / Array – These are made of components called Solar cells which are made of
    semiconductor materials like silicon. The Solar cells convert the sunrays falling on the solar modules
    to electricity.(DC)
  • Balance of Components:
    Inverters : These are devices that convert Direct Current(DC) generated from the Solar Panels to
    usable AC(Alternating Current)
  • Charge Controllers: these devices control the voltage and current supplied to the battery from the
    current generated from the Solar Panels.
  • Battery: These devices store energy in the form of Direct current (DC).
  • Trackers: These are devices attached to the Solar Panels to track sunlight to get maximum Solar exposure.

PV stand for Photovoltaic where the solar cells convert incident sunlight on the solar panels into electricity.

The Solar cells are made of silicon wafers. The solar cells are made of 2 layers: Ntype and the Ptype.
The Ntype loses electrons and the Ptype accepts electrons. When sunlight falls on the solar cells, the solar cells absorb sunlight and when enough of sunlight has been absorbed, the N-type releases the outer most electrons(free electrons) and the P-type accepts the electrons. These electrons are made to flow through a circuit in the solar cells creating electricity.

  • Grid Connected – In case of a Grid Connected system, the output generated from the Solar PV system is connected to a bidirectional meter. The meter ensures current is either supplied to the the building or in case of excess current produced, is fed to the grid. Here the Grid acts as a virtual battery. The system doesn’t work if there is no grid supply.
  • Offgrid- In case of an Offgrid system, the Solar PV system is completely disconnected from the grid. The system can operate with a backup energy system like generator to provide power incase the solar is not generating power.
  • Hybrid – As the name specifies the Hybrid system works as a hybrid i.e it can work either as a grid connected or an offgrid system. This is basically an On-grid Solar PV system with a battery backup.

Both Monocrystalline and Polycrystalline solar modules are made of silicon wafers. Monocrystalline Solar Modules are made of single silicon crystal. They are a lot more efficient in the electron flow. But they are lot costly compared to Polycrystalline panels. The Polycrystalline panels are made by fusing different types of semiconductor materials and less efficient in electron flow compared to monocrystalline panels. But these are a lot cheaper compared to monocrystalline panels. Thin film modules are made by the depositing semiconductor material on a ceramic substrate. There are no silicon wafers used as in the case of Monocrystalline and Polycrystalline solar modules. These too are a lot efficient and produce more energy and are shadow tolerant.

The size of the Solar Plant depends on several factors like:

  • Load of the building
  • Rooftop space
  • Efficiency of the Solar panels

The rooftop space needed depends on the energy output of the Solar panels. More the energy output of the Solar Panels bigger is the Solar PV system and more space it occupies. On an average a 1 kW peak power capacity requires about 100 sq.ft. shadow free area on the rooftop

Major costs(around 80%) would be that of the Solar Panels. On an average a solar pv sytem with a 5 KW capacity costs around 3-4 lakh rupees.

There are a number of factors that can affect electricity produced from Solar PV systems. These include:

  • Solar PV rooftop orientation – The direction of the Solar panels in relation to the incident sunlight determines the Solar exposure that directly correlates with the energy output. Hence Solar Trackers are used along with the Solar panels to track the path of the sunlight.
  • Shading and Solar Soiling – Shading reduces the efficiency of the Solar panels due to reduced Solar exposure.Efficiency can also reduce due to Solar Soiling – It refers to things that may fall on the Solar panels like dust leaves and so on that reduces the efficiency of the Solar panels. Hence Solar Panel maintenance helps in improving the efficiency of the Solar panels.
  • Weather and climate of the place – This affects the amount of sunlight incident on the Solar Panels.
  • Efficiency of the Solar panels – This determines the amount of electricity output by the solar panels in relation to the incident sunlight.
  • Prevailing Temperature – This affects the efficiency of the Solar Panels and in turn the output of the Solar Panels.

Benefits of going Solar:

  • Attractive ROI and IRR
  • Payback of 4-6 years thereafter revenue up to 25 years
  • Reduce your Electricity Bills
  • Attractive PPA with DISCOM
  • Locked in Electricity tariffs
  • Reliable and proven technology
  • Third party sale, REC’s, Carbon Credits
  • Contribute to India’s energy independence
  • Reduce Your carbon footprint

There are several grants provided by the government of India. Banks are also availing low interest loan schemes to promote Solar. Check out the link for more info:

Home owners can avail NetMetering by which they can get credited for the surplus power supplied to the power distribution companies. It lowers energy costs by reducing the dependence on grid power. They are a secure investment unlike utilities which fluctuate from time to time. It also increases the value of the house with the demand for green sustainable homes.

Other Financial Benefits include:

Acceleration Depreciation

  • Invest in solar and claim accelerated depreciation in your business
  • 80% depreciation on WDV of asset for first 5 years reduces the effective capital cost
  • For every Rs. 100 invested in Solar, Rs. 27 is saved in Income Tax in the first year
  • Project Payback period is reduced by more than a year.

Income Tax Holiday
Income tax holiday for 10 Consecutive years for revenue generated from Solar Plant