What is a Photovoltaic System?

  • The word Photovoltaic (PV) is composed of two terms: Photo - Photon which means "light" and Voltaic from "Volt" which is the unit used to measure electric potential at a given point.Photovoltaic systems use cells to convert sunlight into electricity.
  • PV system consists of multiple components, including cells, mechanical and electrical connections and mountings and means of regulating and/or modifying the electrical output.

What are the various types of Photovoltaic systems?

    a) Grid-connected photovoltaic system
  • Grid-connected PV system use PV modules - converting sunlight into electricity, an inverter to convert direct current into alternating current, sub-construction consisting of the mounting system, cabling and components used for electrical protection, and a meter to record the quantity of electric power fed into the grid.
  • b) Off-grid (stand-alone)
  • Off-grid (stand-alone) systems use charge controllers instead of inverters and have a storage battery for supplying the electric energy when there is no sunlight e.g. during night hours.
  • c) Hybrid systems
  • Hybrid systems are the PV systems supported by an additional power source for example, wind or diesel generator.

What are the different components of a solar photo voltaic system?

  • Modules: The function of modules is to turn sunlight to DC electricity.
  • Inverters: The basic function of an inverter is to convert the DC electricity produced from solar modules to AC electricity
  • Charge controller: A charge controller limits the rate at which electric current is added to or drawn from electric batteries. It prevents overcharging and may prevent against overvoltage.
  • Circuit breaker: A circuit breaker in a solar photo voltaic system protects an electrical circuit from damage caused by overload or short circuit.
  • Battery system: If the current is not fed into the grid, a well-designed battery bank is required for storing power generated.

How much do the solar PV modules weigh?

  • Empire’s EPG & EPE series 230Wp Crystalline silicon modules weigh about 20 kg each.

What are the maintenance requirements or other costs for a Photovoltaic system?

  • There is typically little or no maintenance required. Only a periodic inspection is required to ensure that the photovoltaic modules remain clear of leaves, dirt, bird droppings, etc. The modules may be cleaned with water. Other than that there should be no maintenance required, unless there is any technical failure.

How do Photovoltaic panels stand up to hail, wind, hurricanes etc..?

  • Solar electric systems are designed to withstand all weather conditions. Lightning, winds up to 80 miles per hour, snow and extreme temperatures are all things your solar system can handle. However, extreme conditions will temporarily reduce its energy production.
  • The modules are certified and tested to withstand hurricane force winds, and rainstorms. Falling stone, tree or hail do not damage the modules in most cases.

How much roof space does a Photovoltaic system need?

  • As a rule of thumb, a rooftop PV system requires 10-12 square Mtrs of shadow free space per KW of capacity installed.
  • A solar farm using crystalline silicon modules shall require about 4.5acres of land per MW installed.

What do kWp and kWh mean?

  • “Watt” is the unit used to measure power and a kilowatt is equal to 1000 watts.
  • KWp stands for kilowatt peak, which is the maximum power that a solar panel will produce under ideal conditions.
  • Colloquially known as units, kWh stands for kilowatt hour, and is the measure of energy consumed (power time).

Can i get paid for generating electricity?

  • Yes, with the Government Feed In Tariff, we can get paid for generation power using solar modules. A Feed In Tariff (FIT) is a Government incentive scheme to encourage uptake of Micro-generation.

Does Photovoltaic technology need bright sunshine to work properly?

  • Photovoltaic cells not only use the direct component of the light, but also produce electricity when the sky is overcast. PV modules will tend to generate more electricity on bright days than when skies are overcast. It is a common misconception that PV only operates in direct sunshine and is therefore not suitable for use in temperate climates. This is not correct: photovoltaic make use of diffuse solar radiation as well as direct sunlight.

Is efficiency important with solar modules?

  • The efficiency of a module relates to how effectively it can convert the sun’s light. Given that the sun’s light is free a module can simply be made larger to offset a lower efficiency. Only when suitable roof area is at a premium does it make sense to choose high efficiency modules.

How long does a PV system last?

  • Empire solar PV modules come with a 25 year power output warranty. On the electronic components and accessories (inverters, batteries, controllers), the warranties vary as per specifications. But this doesn't mean that PV systems don't produce energy after 20/25 years. Most PV systems installed more than 25 years ago, still produce energy today.

Are Empire solar PV modules certified and approved?

  • Empire Solar branded modules are certified with TUV Rheinland & MNRE compliant, and certified for use the world over.

What is the annual output of a PV system?

  • In most parts of India, a 1 KW system can generate 1250-1500 units (KWh) of electricity in a year. So, for a household using an average of 300 units a month (annual consumption of 3600 KWh), such a system can take care of roughly one-third of the annual energy requirement.

What are the benefits of using Photovoltaic solar power?

    Compared to non-renewable sources such as coal, gas, oil, and nuclear, the advantages are:
  • • Generates free energy from the sun
  • • Has no moving parts to break down thus requiring minimal maintenance
  • • Non-polluting energy reduces emissions: Has no direct impact on the environment
  • • Photovoltaic (PV) cells are modular, you can start with a small system and expand as your needs increase
  • • Systems have a long life & durability. Cells last 25-30 years
  • • Grid-Tie systems allow you to sell excess electricity back to the utility
  • • Can be installed and operated anywhere including areas of difficult access and remote locations
  • • PV cells make no noise and give off no exhaust
  • • Allow the use of electricity in remote areas where it would be expensive or impossible to run power lines
  • • Have electrical power during blackouts
  • • Rebates and incentives available. Several subsidies/ schemes from the Union government, plus state and local incentives.

How much does a solar Photovoltaic system cost?

  • The cost of the system depends on many factors like the size, location and requirement. A grid tied system costs between Rs 150/Wp to Rs. 170 /Wp. Large solar farms cost Rs 9 Crore/MW to Rs 10 crore/MW. The costs for battery-backed systems depend on the size of the battery bank.

What are the financing options for installing off-grid system under JNNSM?

  • • Capital Subsidy
  • 5 % interest bearing loan is given after due diligence of credit appraisal by FIs, NBFC, Micro finance institutions.
  • Boundary conditions for support to off-grid solar PV applications which are yearly revised by the government:
  • There are many National and state solar policies which provide subsidy on solar investment. You can visit the http://www.mnre.gov.in/ for further information.

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