As we enter 2019, solar energy is a term that is heard almost every day, in one form or another. The history of solar energy is as old as mankind.
Until the middle of the 18th century, renewable sources of energy were the only forms of energy available, but then, with the emergence of the Industrial Revolution, fossil fuels began to be exploited. Fossil fuels are a non-renewable energy source. Once a fossil fuel is extracted it does not replenish itself. Burning fossil fuels emits a number of air pollutants that are harmful to the environment and human health. These gases are contributing to the greenhouse effect and could lead to major changes in the Earth’s climate. Thus, leading to more sustainable solutions for renewable energy.
Over the past two centuries, humankind began using the sun’s energy directly to make electricity.
In 1839, Alexandre Edmond Becquerel, a French physicist, discovered that certain materials produced small amounts of electrical current when exposed to light, the photovoltaic effect. He claimed, “shining light on an electrode submerged in a conductive solution would create an electric current”. The photovoltaic effect is similarly related to the photoelectric effect. With both effects, light is absorbed, creating excitation of an electron or other charge carrier (a particle that carries an electric charge) to a higher energy state.
The photovoltaic effect is used when the excited charge carrier is still contained within the material. Thus creating, electric potential or voltage by the separation of charges. The light being absorbed has to have a sufficient amount of energy to conquer the potential barrier for excitation.
The first solar cell was experimented by Charles Fritts in 1883. The world’s first rooftop solar arrangement was installed in 1884 in New York City, but had poor efficiency. The cell was thin, gold coated, selenium. At the time, the cell was less than one percent efficient at converting sunlight to electricity. Fritts’ cell could not compete with Edison’s coal fired power plants.
Almost 60 years later, solar cells became more effective for power usage. In 1941, Russel Ohl developed a silicon p/n junction cell. These cells reached efficiencies above 5% by the 1950’s. To put that into perspective, today, the best silicon solar cells are over 40% efficient.
So why solar? As the Earth’s population continues to grow and electricity prices rise, change needs to occur. The Earth’s population has grown by 173.4 million people since 1950 and electricity prices have risen by 4% over the course of 10 years. The world will continue to grow, and prices will continue to rise as more and more electricity is needed.
By going solar, you will be able to generate your own electricity from the sun and save money over time. The amount you save will vary. This will vary depending on where you live, the system size you decide on, possible shade, climate, and utility rates.
Why go solar in 2019? There is a U.S. Federal Solar Investment Tax Credit, also known as the ITC. The ITC allows the tax payer to take a reduction of up to 30% that is invested into the solar system. This year, 2019, is the last year to receive the full 30%. The reduction will drop to 26% in 2020, 22% in 2022, and 0% after that. Get a head start and take advantage before the year is up.