The purpose of this report is to discuss the history of solar energy and walk through the inventions which have made modern days solar panels possible, the benefits of using solar panels and how effective they can be in the areas where the weather is not suitable for electricity generation using solar panels mostly due to overcast conditions.

Background and History of Solar panel

In theory, solar energy was used by humans very early in history. The first use of solar by humans was in 7^th century B.C. when sunlight was used to light fires with magnifying glass materials. Some centuries later, somewhere in 3^rd B.C. the Romans and Greeks used to harness solar power with mirrors to light fire torches in their religious ceremonies. These types of mirrors were called as burning mirrors. The documented history also tells that Chinese civilization used these mirrors for the same purpose later somewhere in 20 A.D. Another earliest use of solar energy was “sunrooms” which is quite popular these days as well. Direct sunlight is concentrated into a single area using massive windows in these sunrooms. In about 1200 A.D. the Anasazi which is ancestors to the Native Americans used the concepts similar to these sunrooms to capture the sun's warmth during the cold winter season. In the late 17^th and 18^th centuries, researchers and scientists used sunlight to light ovens during their long travels. Sunlight was also used to power steamboats. So, even centuries before the invention of solar panels, the sun's power was used and manipulated for different purposes.

Many scientists have been given the credit for the invention of the solar cells but it can be safely said that it the contribution of all those men we have the present-day solar cells. French scientist Edmond Becquerel is given credit for the invention of solar cells because he was the one to determine that placing two metal electrodes in a conducting solution increases electricity production using light. This phenomenon known as the "photovoltaic effect" proved instrumental in later PV developments using selenium. In 1876 Richard Evans Day and William Grylls Adams discovered that electricity is produced whenever selenium is exposed to sunlight. After a few years of this discovery in 1883, Charles Fritts was the first person who produced the first solar cell which was made from selenium wafers and this is the reason he is most credited with the invention of solar cells. Nowadays, solar cells are made from silicon so some historians consider the actual inventors of the solar cells to be Gerald Pearson, Calvin Fuller, and Daryl Chapin who created the first silicon-based photovoltaic cell at Bell Labs in 1954. This is considered the truest invention of solar cells as this solar cell could power electric devices for several hours of the day. This solar cell could only convert the solar cell to electric energy at only 4% efficiency which is quite low according to modern standards (Solar).

The modern solar cells have evolved a lot over time. Present-day solar cells cost a lot less than they used to in the past and due to this, the commercial use of solar panels is increasing at a rapid rate as more and more people can afford it. In 1956, a solar panel used to cost $300 per watt which reduced to around $100 per watt in 1975 and nowadays this has reduced to only $0.5 per watt.

Benefits of Using Solar Panels

There are many benefits of using solar panels using other energy sources. They save a lot of costs compared with other energy sources and they are also environmentally friendly. They also contribute to energy independence which means producing own energy for your needs. These are the main benefits of using solar panels:

Reduction in energy bills of Solar panel

The energy produced by solar panels is very cheap compared with energy produced from other sources. The solar energy is produced using the sunlight which is always available, hence the cost of production is reduced a lot; there is just the initial cost of buying solar panels and installing them. The maintenance cost is also non-existent which makes energy produced from solar panel super cheap. Even on cloudy days, the diffused sunlight is good enough for producing some energy.

Reduction in air pollution of Solar panel

A lot of pollutants are produced using fossil fuels and these are responsible for the increase in air pollution. The increase in air pollution is also responsible for the production of smog which has devastating effects on the environment and also on the general public's health. The energy produced by solar panels has no such side effects making it environmentally friendly. This is the reason the energy produced by solar panels is called clean energy which has zero contribution toward air pollution (Solar).

Reduction in water usage of Solar panel

If the energy production does not use fossil fuels like coal etc. it usually uses water somewhere in the production process. Both hydroelectric and nuclear energy production uses water in an enormous amount of water; the water can be used somewhere else. Water scarcity is increasing and it poses a threat to all life forms on this planet. Also, dams that are used to store water have irreversible and damaging effects on the local ecosystem and animal habitats. As no water is used during the solar energy production, the water scarcity issue can be reduced if not resolved.

Reduction of dependency on non-renewable energy sources of Solar panel

Solar energy makes people energy independent as they can produce energy for their own needs and wants. But at the same time, solar energy will reduce our dependence on the use of non-renewable energy sources. The non-renewable sources like petroleum, coal, etc. are called non-renewable for a reason because one day even if not in the near future these resources will deplete. So, it's better for mankind to shift from non-renewable sources to renewable sources as soon as possible so that we can keep on using those non-renewable resources in places where we don’t alternatives to those (Holowka).

Helps fight climate change of Solar panel

As we keep on using fossil fuels, we keep on dumping more pollutants are carbon dioxide into the air around us. As the levels of these pollutants are carbon dioxide is increasing, the climate is changing a lot. The ozone layer is depleting a lot and it is causing global warming. The earth's temperature is increasing day by day, which is also a threat to a lot of species. The weather patterns are changing around the globe and these have become volatile and sudden. Solar energy is one of the many ways which can equip us to combat this ever-changing climate issue.

Discussion of Solar panel

The integral part of the solar system is a solar panel, where the solar panel collects sunlight and converts it into another form of energy. Now discuss some types of solar panels

Types of solar panel of Solar panel
Monocrystalline solar panel of Solar panel

The purest form of the solar panel is called monocrystalline solar panel. It salient features are uniform dark look and round edges. The take less space, they produce the highest electrical power per area unit, and they also have the longest life. These features also make them the costliest type of solar panels. Their main selling point is that they are least influenced by high temperatures and can still work pretty effectively.

Polycrystalline solar panel

These solar panels usually have square shape, and their edges are not cut. They usually have a spotted look with blue color. They are cheaper than Monocrystalline solar panels as they are made by softening crude silicon. They have less efficiency compared to Monocrystalline usually around 15%. Their life expectancy is also lesser than Monocrystalline solar panel and higher temperatures have a greater impact on these.

Thin-film: Amorphous silicon solar panel

Thin film solar panels are made using thin films photovoltaic material such as silicon or cadmium etc. These materials are deposited on a substrate such as glass or metal etc. Their demand is the lowest compared with the other types of solar panels and due to this reason they are the cheapest as well. Their cell efficiencies are high They are also not greatly influenced by high temperatures which is a plus point.

Concentrated PV cell of Solar panel

Concentrated PV cells are somewhat different from conventional photovoltaic cells. They usually use curved mirrors or lenses to focus sunlight onto a solar cells which enhances the energy produced by them. They have an efficiency in the 40 percent range which makes them light years ahead of other technologies. They also usually have a cooling system in them as well which also contributes to an increase in the efficiency as well (Premierenergy).

Cost of Solar Panel

The usages of the electricity averages annually are approximate 11,00KWh in the United States. Where the solar panel generates their own power which is therefore offset by the monthly electricity bill. By the installation, the solar panel is not cheap, where the average residential is 5kWh by the size of the system among the $3 and $5 per watt or the $15,000 to $25000 before the tax credit. Whereas most of the systems do not obtain great maintenance as well as it is also designed for 20 years which also has a little change amount of electricity produced.

Solar Panel used in rainy, cloudy areas and snowy areas of Solar panel

The solar installations generate renewable, clean energy around the year-round, where the solar panel produced the electricity more efficiently in the cold weather. During the winter season, the solar panel would also brighten the day and home. The working of the solar panel, even in the winter months is that the sunlight hitting the solar panel which would also generate electricity. Then in the cold climate and rainy areas are optimal; for the efficiency of the solar panel. In the cold climates, the solar panel supplies dependable energy. From the winter conditions, the solar panel protects your home, where the cold temperatures also increase the production of solar electricity which could also be used to store for the future. In winter conditions, the energy production as well as efficiency which diminish somewhat (Sunrun.com). By the cold temperature, the energy production, as well as the efficiency of the solar panel, also improved. Whereas solar panel creates the electricity from the sunlight and forms the sun's heat. By the lighter snow, the sunlight navigates the around the solar panels which also maintain energy production. It may sound counter-intuitive but the energy produced by solar panels in low temperatures is more compared to the energy produced on hotter days. As the temperature is low in the solar panel, the electrons have low energy compared to the hotter days, so the sunlight excites these electrons and causes a greater energy differential which causes more energy to be produced. Panels are equipped to deal with snow as well but they should be installed at an angle so that snow clears itself without any other intervention. And in case there is a lot of snow and it's not falling itself, people must contact professionals and do not take matters into their own hands as they can damage the panel (Igs.com).

Conclusion of Solar panel

Summing up all discussion it is concluded that, humans have been using solar energy way before the invention of solar panels to perform different tasks. Solar panels have revolutionized the energy industry. Solar energy empowers people to be energy independent and at the same time reducing the environmental impacts caused by other energy sources. Modern solar panels are equipped to deal with extreme weather conditions and at low temperature, the energy produced by solar panels is high compared to the energy produced at high temperatures.

Works Cited of Solar panel

Holowka, Taryn. Top four benefits of installing solar panels on your home. 5 April 2017. <https://www.usgbc.org/articles/top-four-benefits-installing-solar-panels-your-home?fbclid=IwAR3SairIwF3bF3h5flCT4OiFrxb6k2AWdmgod_NBVVmF1KO0gCzGhWjJNKk>.

Igs.com. HOW DO SOLAR PANELS WORK IN SHADE OR BAD WEATHER? 2019. <https://www.igs.com/energy-resource-center/energy-101/how-do-solar-panels-work-in-shade-or-bad-weather>.

Premierenergy. 2019. <https://www.premierenergy.com.pk/solar-panels-in-pakistan/>.

Solar. 5 Benefits of Solar Energy to the Environment. 2 February 2019. <https://www.vivintsolar.com/blog/benefits-of-solar-energy-to-the-environment?fbclid=IwAR1u19MMZLS7SDTKRWLyqHGkjn562VVRtj6QpMoeGU99xknLqxHl7mqjcy8>.

—. History of Solar Energy: Who Invented Solar Panels? 24 October 2018. <https://www.vivintsolar.com/blog/history-of-solar-energy>.

Sunrun.com. Do Solar Panels Work in Cold Weather? 2019. <https://www.sunrun.com/go-solar-center/solar-articles/do-solar-panels-work-in-cold-weather>.