Solar Power – What is it and how it works.

We all know (or have been told) that solar power is simply power provided by the sun. But how does the process actually work? As an amateur solar enthusiast I’ll try and explain the process for you so that you have a better understanding of the entire process from sunlight (or light source) to the end result of power being produced.

What are Photovoltaics?

The term “photovoltaics” has been gaining popularity in the energy industry. Most countries—especially the industrialized and economically prosperous ones—are finding themselves in short supply of traditional energy sources to ensure that their industries are adequately powered. Fossil fuels have been the traditional source of energy for centuries, but they are not sustainable and might run out over time. Rising oil prices have also clued many nations in how fossil fuels can be vulnerable to depletion. Plus, the rising levels of pollution in many areas of the world are ringing alarms everywhere.

Experts have been searching for clean and sustainable sources of energy for decades, and they have made a breakthrough: harvesting sunlight and turning it into energy that can power all our wonderful inventions and innovations. This method of sourcing energy from a clean and renewable source—the sun—is known as photovoltaics. This method involves collecting solar radiation and turning it into electrical power through the use of semiconductors.

The Photovoltaic Effect

Harnessing the power of the sun and turning it into electric currents is powered by the photovoltaic effect. Simply put, the photovoltaic effect involves creating electric currents or voltage in a certain material by exposing it to light. First observed by a French physicist named Edmond Becquerel in 1839, the photovoltaic effect is greatly influential in the development of the solar power industry. Becquerel is also credited for creating the first photovoltaic cell in the world.

In his experiments, he discovered that silver chloride (placed in an acidic solution) connected to several platinum electrodes could generate electric currents and voltage when placed under light. As recognition for this breakthrough experiment, the photovoltaic effect is alternately known as the Becquerel effect.

Clean and Sustainable Source of Energy

Many scientists and energy experts believe that using photovoltaics in power generation is the clean and sustainable way to go. This seemingly complex technology is powered by the best kind of renewable energy our planet has: the sun. Sunlight is not only abundant (during daytime, of course, and more so during warmer weather and in areas near the equator), but is also distributed in almost every corner of the planet.

One of the major advantages of photovoltaics is that generating power through this technology does not produce environmental emissions during the process—therefore reducing the pollutants released into the environment during power generation.

The technology of photovoltaics is well-proven and used for more than fifty years, with more and more countries and industries building their own systems to supplement their use of electricity and other sources of energy. In the future, energy experts are hoping that photovoltaics can fully take over the other means of electricity generation.

Photovoltaics Around the World

As of 2013, the use of solar power for electrical energy has reached a record height of 136 GW, which experts approximate to be enough to meet 0.85% of the world’s electricity demand. China, one of the world’s leading consumers of fossil fuels, has a fast-growing market for photovoltaics. Germany, long known to be one of the world’s leaders in technology, is the largest producer of sun-sourced electrical energy; the country uses six percent of photovoltaic energy for its electricity needs.

Photovoltaics – How It Works

How Photovoltaics Work

Solar power is credited to be one of the most important breakthroughs of the last century. Harnessing the power of the sun is seen by many scientists and energy experts as the solution to our dependency on fossil fuels, which are not only contributing to environmental pollution, but can also be depleted over time. Photovoltaics has been used in different parts of the world as a means to supplement electricity demands, and energy experts are optimistic that the growth of the solar power industry means that we could expect a higher annual generation of electricity through this process.

Photovoltaic Cells

The word “photovoltaic” was derived from the Greek word “phos” (light) and “volt,” which was derived from Alessandro Volta, the Italian physicist who invented the electrochemical cell. Photovoltaic cells, also known as solar cells, is basically a type of electric device that has the ability to convert light energy into electricity through the photovoltaic effect.

The photovoltaic effect is also known as the Becquerel effect, named after the French physicist Edmond Becquerel who discovered it in 1839. At the tender age of 19, Becquerel experimented with silver chloride (in an acidic solution) and platinum electrodes. When connected and exposed to light, the chemical and the electrodes generated electric currents and voltage. This “little” experiment won Becquerel a seat in the Royal Swedish Academy of Sciences.

Photovoltaic cells are the core of the technology. There are three basic attributes to a photovoltaic cell. First, it has the capacity to absorb light and to generate excitons or electron-hole pairs. Second, it has the capacity to separate charge carriers with opposite types. Finally, it has the capacity the separate the extraction of charge carriers to an external circuit connected to it.

Photovoltaic cells are made with semiconductor materials, with silicon as the most used material in the industry. The solar cells are semiconductor wafers, which are treated with chemicals that allow the formation of electric field.  When exposed to light, the electrons on the semiconductor material will be loosened from the atoms they are attached to. The electrical conductors connected to the positive and negative sides of the solar cell will then form an electrical circuit, and the loosened electrons will then be captured as an electrical current.

Photovoltaic Modules

When connected to each other and mounted on a frame, solar cells will form a photovoltaic module. These modules are often designed to generate and supply electricity at a specified voltage, with 12 volts being one of the most common kinds of solar modules. Since these modules depend on solar power, the amount of electricity that they can generate is dependent on the amount of light that they absorb.

Photovoltaic Arrays

When wired together, multiple modules form an array. The larger the array (or, the more modules grouped together), the higher amount of electricity it can produce. Solar arrays generate direct-current (or DC) electricity, and can be connected in either a parallel or series electrical arrangement to deliver the current and voltage combination needed.