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What is the efficiency of crystalline solar modules used in the rooftop Solar Photo Voltaic  system?

Crystalline solar modules/panels are the most commonly used solar modules for rooftop applications. Module efficiencies vary from 13-17% with the most commercially viable ones being in the 14- 15% range.

What would be an appropriate system size for my facility/home?

The sizing of the system depends on the following

  • Connected Load and energy required from Solar
  • Rooftop space available
  • Budget

Where does one need to place the SPV system?

The panels are best suited to face the south direction for maximizing generation and in a shadow free area such as the rooftop of any building.

 

What will be the approximate space requirement for a SPV system?

In general, a 1 kWp system will require approximately 120 Sq ft or 12 Sq m of shadow free space.

What maintenance is required for the Solar Photo Voltaic system?

A Solar Photo Voltaic system in a grid tie configuration requires nil or almost no maintenance as the system has no moving parts. Occasional cleaning of the panel with a low pressure water jet is advised to make sure generation is not affected.

Battery based systems require periodic maintenance of the batteries to ensure longevity. Batteries should be regularly and carefully maintained. A visual inspection should be done to assess the general state of the batteries, check for any leaks, cracks or corrosion at the terminals or connectors.  Corrosion at the battery terminals is seen as a white coating around the terminals. Cleaning should be done once a month.

How is a Solar Photo Voltaic(SPV) system installed on the roof?

The modules of the PV system are mounted on structures and placed on the roof of buildings.  These can be done with very minimal or no grouting work and limits damage to the roof top.

How much electricity will my Solar PV system produce?

The electricity generation of the PV system installed on your roof varies depending on geography, climate conditions and type of system installed.

A grid connected system is usually efficient when compared to a battery based system. A grid connected system can generate approximately 4-5 units every day, whereas a battery based system will generate 2-3.5 units every day.

 

 

 What are the rebates provided by the government for installing rooftop solar?

Homeowners have an opportunity to avail ~30% capital subsidy for your solar PV installation for up to 1kW whereas commercial or profit making enterprises can avail of a 30% capital subsidy up to a maximum system size of 100 kw.

Commercial establishments can also avail accelerated depreciation, under which 80% of the system cost maybe written down against profits in the 1st year itself, leading to a saving in tax outflow for profitable enterprises.

 

Can a solar rooftop system be installed on any kind of roof?

The Solar PV system can be installed on any kind of roof, except they may require special mounting structures. Some types of roofs are simpler to work with than others. Flat roofs facing south direction are the most appropriate and easiest to work with.

How much does a rooftop Photovoltaic system cost?

There is no single or simple answer; however solar subsidies and other incentives can reduce the cost of the PV system. Costing of the system primarily varies depending on whether it is a grid connected system or battery based system. The quality of components used also has a strong bearing on the total system cost.

A grid tie system (without batteries) can give you a payback within 4 years or less.

What are the different kinds/ types of technology/ modules available in the market now?

Crystalline and thin-film are two of the most commonly used technologies of manufacturing solar cells/modules.

In Crystalline Silicon technology, thin wafers are cut from Silicon (Si) block, from which cells are manufactured. The modules are then made by interconnecting a number of cells in various combinations.

In thin film technology solar cells are made by depositing one or more thin layers (and hence called thin film) of amorphous Silicon on a polymer substrate.