What is Solar Energy?

According to scientific findings, the earth intercepts lots of solar power, 173 trillion terawatts to be specific. That’s literally ten thousand more power than the entire world population utilizes. This validates the fact that the sun is the most plentiful source of energy on the entire globe and that it could one day be the most reliant source of energy.

Traditionally, the world’s electrical needs have been fulfilled by fossil fuels like oil, natural gas, and coal. However, these energy sources have two main negative impacts:

They play a bigger role in global warming and acid rain pollution, which negatively impacts many animals, plants, and humans in the environment.

Few countries have full access to fossil fuel-based energy resources, which can lead to global political and economic instability.

The best alternative is solar energy, which is a renewable resource, meaning it will not become unavailable. It provides an unlimited, steady supply through time. Solar energy is also a green source of energy because it does not emit pollutants during the energy production process.


So, What is Solar Energy?

Solar energy is the energy that is produced by the sun in the form of heat and light. It is one of the most renewable and readily available source of energy on planet Earth. The fact that it is available in plenty and free and does not belong to anybody makes it one of the most important of the non-conventional sources of energy. Solar energy has been used by people since ancient times by using simple magnifying glasses to concentrate the light of the sun into beams so hot they would cause wood to catch fire.

Mainly, Solar energy can be used to convert it into heat energy or it can be converted into electricity. Solar energy is energy harnessed from the sun. It’s harnessed in 2 main ways:

  1. Through production of electricity

This technique utilizes Solar Photovoltaic (PV) devices or solar cells that convert the sun’s energy into electricity. Photovoltaic devices produce electricity right from the sunlight through an electronic process that naturally occurs in particular material types known as semiconductors.

Electrons contained in these materials are let loose by solar rays are stimulated to travel via an electronic circuit, sending power to the grid or directly powering electrical devices. This form of energy can be used to power solar watches, calculators or traffic signals. They are often used in locations that are not connected to electricity grid.

  1. Solar collector devices

A solar thermal collector harnesses heat by absorbing the sun rays. This technique harnesses the sun’s energy to heat up water (solar hot water panels) for home use such as water heaters, hot tubs, and swimming pools. The concentrated solar power plants utilize the more complex collectors to produce electricity by heating a liquid to turn a turbine connected to a generator. Simple collectors are normally utilized in commercial and residential buildings for space heating.

The solar energy converted into electricity can be instantly used to power lights or many other devices. Better still, it can be stored in batteries for future use. Solar cells normally generate direct current (DC)-type electricity. However, it can be converted into AC (alternating current) using a device known as an inverter. Solar energy converted into heat energy for the purpose of water heating can be utilized instantly or stored as hot water in tanks to be used later.

Solar energy can be broadly categorized as active or passive solar energy depending on how they are captured and utilized. In active solar energy, special solar heating equipment is used to convert solar energy to heat energy whereas in passive solar energy the mechanical equipment is not present. Active solar include the use of mechanical equipment like photovoltaic cells, solar thermal collectors or pumps and fans to trap the solar energy.

Passive solar technologies convert solar energy to heat energy without use of active mechanical systems. It is mainly the practice of using windows, walls, trees, building placement and other simple techniques to capture or deflect the sun for use. Passive solar heating is a great way to conserve energy and maximizing it’s utilization. An example of passive solar heating is what happens to your car on a hot summer day.

How Solar Energy is Converted to Electricity?

The initial step to convert solar energy to electricity is to install Photovoltaic (PV) cells or solar cells. Photovoltaic means light and electricity. These cells arrest the sun’s energy and convert it into electricity. These solar cells are made of materials that show photovoltaic effect, meaning when the sun rays strike the Photovoltaic cell, the photons of light spook the electrons inside the cell triggering them to start flowing, ultimately producing electricity.

When looking to buy solar panels, it would be beneficial to know the options available in the marketplace. Here is an outline of the main ones:

  • Polycrystalline – This utilizes Multicrystalline Silicon
  • Monocrystalline – This is ideal for small spaces
  • Thin Film – Typically bigger in size and a lot more efficient during the day

The disparity between the material used to manufacture monocrystalline and polycrystalline lies in the constitution of the silicon substrate utilized to manufacture solar cells and ultimately, solar panels. As the name suggests, polycrystalline implies numerous crystals, while monocrystalline implies a single crystal. The larger the crystal sizes, the more efficient the solar cells, which explains the reason monocrystalline cells are normally 10 – 15% more efficient than the polycrystalline crystals.


How Solar Panels Work?

The solar panel should be mounted on an open area that is not obstructed by trees or any installation. A roof is normally the best bet. It’s then wired into the building through the inverter. The inverter is a device that converts AC (alternating current) to DC (direct current). So, in this case, the alternating current is the energy created by the solar panels. This solar energy is converted into AC. The reason for converting the direct current into alternating current is to enable the energy to be used by various home appliances just the way you power your electronics with normal electricity.

Considerations to Keep in Mind Before Installing Solar Panels

Before taking any step to install solar panel in your home, make sure the solar power befits you and your home. Then, ensure that sufficient sunlight is available in your locality. The suitability of solar energy varies considerably with how much sun an area receives. If your area does not receive sufficient sunlight, investing in solar panels will not be the best cause of action.

After determining that your area receives adequate sunlight, make sure installation space is available. We’ve learned that solar panels are quintessentially set on roofs of buildings. While this is laudable, it’s not the only option. If you have an open space to spare in your backyard, it would be an ideal spot for ground mounts. The backyard option is ideal for those whose roofs are heavy shaded or not structurally essential for solar panels. Also, it is paramount to know the local laws regarding solar panel installation to avoid getting into trouble with the local authorities. You can get this information from your local solar energy consultant

Environmental Impact

Although solar energy is considered to be one of the cleanest and renewable sources of energy among the available sources but is has some environmental impacts too. Solar energy uses photovoltaic cells to produce solar power. However, manufacturing the photovoltaic cells to produces that energy requires silicon and produce some waste products. Inappropriate handling of these materials may lead to hazardous exposure to humans and the environment. Installing solar power plants may require large piece of land, which may impact existing ecosystems. Solar energy does not pollute the air when converted to electricity by solar panels. It is found in abundance and does not help in global warming.

Future of Solar Energy

Before we indulge in any discussion about the future of solar energy, we must first put some facts into perspective:

Climate change is a real phenomenon and a big threat to humans and other forms of life on planet earth.

If we are serious about reducing our children’s risk of bearing the brunt of the grave effects of climate change, we must take the front seat in minimizing the rate of greenhouse gas emissions by 80% by the turn of 2050. Because 60% of global emissions results from energy use, we have the duty to initiate low carbon emission technologies at a huge scale beginning today.

Solar Energy is the largest energy resource, by far

Whether renewable or not, other sources of energy apart from geothermal, nuclear and tidal, stem from sunlight. Fossil fuels are simply solar power incorporated over decades (using remains of animals and plant life) as batteries. Wave and wind power owe their origin to solar power. Amongst low-carbon emission energy sources, it’s just wind, solar and maybe nuclear that can achieve the terawatt (TW)-level deployment required to satisfy the constantly growing energy demand.

There is significant scale up of solar photovoltaic technologies.

Photovoltaic technology is scaling up quicker than any energy technology. The capacity of all installed photovoltaic devices has doubled every 2 years since 2000, going up to 200 gigawatts-peaks (GWp) in the year 2014. This exponential growth shows no sign of abating. If the fast growth of photovoltaic technologies continues at such extraordinary rates, solar energy, without any shadow of doubt, would satisfy the entire world’s power demand within the next decade.

That said, the future of solar energy is nothing but bright considering large economies like U.S.A, and China are committing billions of dollars to the development and installation of solar energy technologies. Also, the fact that solar energy is a renewable resource makes it appealing to most governments that are scaling down on dependence on fossils fuels.

Image credit: WDnetStudio , succo


Rinkesh is passionate about clean and green energy. He is running this site since 2009 and writes on various environmental and renewable energy related topics. He lives a green lifestyle and is often looking for ways to improve the environment around him.