What does solar energy mean to you? If you’re reading this, there’s a good chance you have a sense of humor about the topic and can answer that question with a giggle. For the rest of us, let’s dive into the world of solar energy and try to put a new term or definition in every article. Ready? Let’s go.
Solar
Let’s start with the basics and work our way up: Solar is the scientific name for the energy derived from the Sun. The Sun is the source of all life on Earth, and thanks to solar energy, we can use light to illuminate our homes at night and power our electronics with clean electricity in the day. In addition to the Sun, solar energy can be found on planets like Venus, Mars and Jupiter. While they don’t have a solid surface, the Sun’s heat is still able to reach the surface, causing it to glow. This is why we can see the dark side of the Moon from the Earth. When the Sun is directly overhead, we can typically see it illuminated by the afternoon sun glow, which is a beautiful sight and a testament to its energy.
The most recognizable symbol or name for solar energy is, of course, the Sun. As far back as 1847, scientists were able to isolate and identify the Sun’s chemical composition. We now know that the Sun is composed of hundreds of elements (more than 99% of it is hydrogen and helium), which are all produced as a result of nuclear fusion in the star’s core. However, it is very unlikely that any of these elements were present in the star’s original state. The elements were either formed as a result of supernovae (Type Ia or Ib) or became available for use in stellar interiors as a result of thermonuclear burning (Type II and III supernovae, as well as novae and hypernovae).
Energy
Like many renewable energy sources, solar energy is a form of sustainable energy. Unlike other renewable energy sources, however, solar energy is always available and doesn’t require very specific environmental conditions to generate it. The amount of solar energy we can get depends on many factors, including the size of the Earth, the inclination of the Sun’s axis and the distance between us and the Sun. Luckily for us, the Sun is always providing energy to our planet, so we don’t need to worry about running out.
When the Sun shines on a surface, it heats the surface and in turn the air around it up to a certain point. Once the air reaches a certain temperature, it becomes lighter and thus more buoyant. This is why when the Sun shines down on a surface, you generally feel warmer than you would if you were outside in the cold. This is why when the Sun shines in the sky, we can see its warmth reflected by the colors of the Sun coming through the clouds and diffused by the atmosphere. If we look at the sky during the day, we can see that the Sun is generally surrounded by a band of blue sky. This is due to the presence of many molecules in the atmosphere that scatter blue light more than red light. When you look at the Sun this way, it gives the Sun a glow that is mostly red in color.
Another way we can represent solar energy is in terms of Joules. One Watt is equal to one joule per second. One wattage hour is equal to one joule per hour. One kilowatt hour is equal to one thousand Joules. These units are used because the power generated by the Sun, or any other source of solar energy for that matter, fluctuates based on many factors. The fluctuation is generally expressed in terms of Wattage (W), and there are many different units of Wattage, including the venerable Watt and the more modern version, the watt. Let’s use Watts as an example: we’ll refer to one particular watt of solar energy here on Earth as one solar Watt. If we have 10 Watts of solar power, we’ll say that it is 10 solar Watts or 10 solar W. If 10 solar W are available, we could use them to power a home appliance such as a water heater or a refrigerator. If we have 100 solar W, we’ll write it as 100 solar W or 100 solar W. If 100 solar W are available, we could use them to run a whole house or an entire office building. Remember, you can’t always assume that more is better. Sometimes less is more, and in this case, the less wattage the better, especially if you want to keep the cost of your electricity as low as possible.
Photovoltaic
The power that comes from the Sun isn’t limited to heat; it can also be converted into electricity through the use of a device known as a photovoltaic cell (or simply a solar cell). A photovoltaic cell is made of layers of atoms arranged in such a way as to allow the free movement of electrons. When light of a particular wavelength strikes a photovoltaic cell, electrons are excited and move about within the atom. This creates an electric field within the cell and allows for the flow of electrons through the external circuit. Photovoltaic cells have the property that when light is shined on them, they convert the light into electricity, which means they don’t consume energy when there is no input. This efficiency reduces our dependence on fossil fuels and decreases our carbon footprint. In addition, the photovoltaic cell doesn’t generate any harmful byproducts during its operation. This is one reason why many people choose solar energy over other, more traditional sources of electricity when it comes down to powering their homes.
In 1847, German physicist Georges Cleanthes first discovered that certain elements could produce electricity when exposed to light. Over the years, chemists and physicists have determined that there are more than 180 elements that can be used to create photovoltaic cells. However, only the top three elements, namely, silicon, germanium and cadmium telluride, are economical and efficient under normal circumstances. Most solar cells are silicon based, which makes up the majority of cell membranes today. Cadmium telluride cells are most efficient when converted into solar panels but are very expensive to produce. On the other hand, germanium cells can also be used to make flat-panel displays and laser diodes. The most widely used semiconductor is, of course, silicon, which is why most cells are made of this material. In addition to giving us electricity, most solar cells can also be used to detect light and thus can be used as photosensors. This is why many people choose solar energy over other, more traditional sources of electricity when it comes down to powering their homes.
PV (photo-voltaic)
In addition to being used for solar cells, the term PV (photo-voltaic) can also be used to describe any device that can generate electricity from light. The most well-known photovoltaic cell is the solar cell, but as we discussed above, not all solar cells are created equal. There are many different types of solar cells with varying properties and efficiencies, which are all measured in terms of photosensitivity, or how well they are able to convert light into electricity. In order to choose the right type of solar cell for your needs, it is essential to know the amount of light that you will be receiving. This is where most people run into trouble because they either don’t know how much light they are receiving or can’t calculate it accurately based on the location of your solar panel and the amount of time it takes to get to that location. The further you are from the Sun, the less efficient your solar cell will be. This is why some people choose to locate their solar panel near a window, where they can get the maximum amount of light possible. Once you know the amount of light that you are receiving, it is much easier to choose a solar cell that will be effective in converting it into electricity. This brings us to our next topic…