Photovoltaic Energy: A Conceptual Overview

Photovoltaic energy, also known as Photovoltaic solar energy, is a pollution-free, renewable, and inexhaustible source of energy that utilizes solar power to generate electricity. 

The sunlight gets converted into electrical energy via a technology based on the principle of the photoelectric effect. As per this principle, some specific materials have the capability to absorb particles of light (photons) and release electrons to produce electricity.

Photovoltaic energy can be generated in different installations, from small generators for household consumption to large photovoltaic solar plants producing electricity on a commercial scale.

Benefits of Photovoltaic Energy

• Photovoltaic Energy is completely renewable, clean, and everlasting energy. It does not exhaust like fossil fuels or lead to the generation of any waste. Hence, it promotes sustainable development.

• Photovoltaic energy systems are modular. They can be fitted in installations varying from large-scale ground-mounted systems to smaller, residential roof-mounted solar systems.

• In photovoltaic systems, batteries can be installed for storing additional electricity. The additional electricity can be used afterward.

• PV energy systems are highly advantageous specifically for rural or remote areas. It’s perfect for places where electricity is scarce as well as for regions that receive adequate sunshine across the year.

• Photovoltaic energy systems do not need high maintenance.

• Photovoltaic energy leads to the creation of green jobs. It uplifts the local economy by way of innovative projects.

How Does Photovoltaic Energy Work?

Photovoltaic solar energy is an innovative technology that generates electrical energy from the sunlight. The PV technology involves the use of semiconductors for the creation of power via the photoelectric effect.

• In a photovoltaic cell, the sunlight dissociates electrons from their host silicon atoms. 
• The electrons then capture the micro packets of light energy known as photons and transmit sufficient energy to propel the electron from its host atom. 
• There is a one-way covering close to the surface of a PV cell, that is the PN-junction. 
• The PN-junction is created when micro quantities of phosphorus are diffused into a thin wafer of silicon to a depth of about one micrometre.

As a free electron passes through the PN-junction, it cannot go back easily. Due to this, a negative voltage gets created on the surface that faces the sunlight and a positive voltage on the back surface. 

Surfaces in the front and backside can be connected through an external circuit to draw out current and power from the solar PV cell.

What are Photovoltaic Energy Systems: A Review of PV Components

A Photovoltaic cell is the fundamental building block of a photovoltaic energy system. Individual cells are manufactured in different sizes, from 0.5 inches to around 4 inches. 

However, an individual cell usually generates only 1 to 2 Watts of power. It can only fulfill the electricity requirement for very small applications, like offering power to wristwatches.

To enlarge the power output of PV cells, they are connected electrically in a weather-tight, packed larger unit, called a Photovoltaic panel or module. 

PV panels come in varied sizes, as per the amount of electricity they can generate. Notably, the electricity production capacity in a PV panel or module expands with the number of cells (or the surface area) in the panel. 

Solar photovoltaic panels can be used individually or connected in groups to establish a photovoltaic energy system or array. 

A PV solar system can consist of two to hundreds of PV panels. In a photovoltaic solar system, the number of PV panels determines the total amount of electricity that system can produce.

Further, one or more arrays of photovoltaic energy systems are connected to the electrical grid as part of a vast photovoltaic system. Thanks to their modular structure, PV systems can be established to fulfill all types of electric power requirements from domestic to commercial-level.

Apart from PV panels, the PV solar systems also include mounting structures, solar inverters, AC and DC cables, AC and DC combiner boxes, Earthing strips, Earthing cables, lightning arrester, and MC4 connectors. All these components make a solar system complete. 

Applications of Photovoltaic solar energy

Photovoltaic energy has various applications. The smallest photovoltaic energy systems are wristwatches and power calculators. 

On the other hand, bigger solar systems can:

• Supply electricity to pump water and power communications equipment
• Supply electricity for domestic as well as commercial use.

Large photovoltaic energy systems can supply the electricity in isolated locations where the electricity distribution systems do not exist or in locations that face scarcity of electricity. 

Also, it can supply electricity to an electric power grid. Vast PV solar farms, in which PV panels are spread over many acres, can produce utility-scale power. These large PV systems supply power into municipal or regional electric grids.

Pricing and Market Analysis of Photovoltaic Energy Systems

Photovoltaics reign over the global solar market. Till now, photovoltaic energy system installations have found extended use in various niches, including the consumer electronics market, remote area power supplies market, and satellites.

Lately, there has been a considerable fall in the prices of solar PV panels. Also, the industry has scaled up significantly. 

The prices of systems are expected to range between Rs. 1,58,112 to Rs. 2,37,168 per kilowatt. But, these prices are never fixed. They change almost every month. 

Solar photovoltaic electricity costs less than both domestic-level and commercial electricity from fossil fuels. In many places, the prices are competitive with wholesale conventional electricity.

Conclusion

Photovoltaic energy is a clean, renewable source of energy that uses solar radiation to produce electricity. It works on the photoelectric principle. 

Notably, solar energy acts as a feasible alternative to conventional sources of energy. We hope that the photovoltaic solar energy systems can lead us towards independence from fossil fuels and resolve environmental issues.

FAQs

Q1. What is the life of photovoltaic solar energy panels?

The life of a solar PV panel depends on distinct variables, including the quality of the panel, the climatic conditions, etc. On average, a PV system can last for about 30 years.

Q2. Can photovoltaic energy offer standalone power?

Yes, photovoltaic systems offer standalone power. They can duly fulfill the electricity requirement of water irrigation pumps, stream-flow gauges, street lights, temporary traffic signals, parking meters, emergency phones, radio transmitters, remote guard posts, etc.

Q3. Do PV solar panels also produce power at night?

The amount of power your photovoltaic solar energy system can generate relies on sunlight. 

Therefore, your solar panels will generate less energy on cloudy days, and no energy is produced at night since there’s no sunlight.