The sun is incredibly powerful with energy that’s unfathomable. Its luminosity (referenced in Joule per second) is 3.8 x 1026 and when converted into mass of energy, it equates to approximately 4,000,000 tons a second. On earth, the energy we receive from the sun is a mere 4.5 pounds per second, but amazingly, it only takes less than 10 seconds of that energy to power an entire day.
With such abundance of energy from the sun, we can easily use it to power almost anything we can think of. With the advancements in solar technology, we can bring clean, renewable energy into our homes and businesses to power our machines, products, and devices. Today’s modern photovoltaic solar panels have much higher energy conversion rates between 15% to 23%, a far cry from the first ever solar panel developed in 1883[1] with an efficiency rating of only one to two percent.
How we achieve electricity
Since the start of the industrial revolution in the mid-1700s, we’ve consistently used a variety of means to create energy including the burning of fossil fuels and other natural resources. That energy was applied to mainly power machines for building things, and today we use it for practically everything. For decades, the way we generate electricity for most of the U.S. is from electric power plants that use a turbine or similar machine to drive electricity generators. “The fuels or energy sources used for steam turbines include biomass, coal, petroleum fuels, natural gas, as well as geothermal energy, nuclear energy, and solar thermal energy.”[2] It’s now being realized by society and government that we don’t have an infinite amount of natural resources to sustain our rising energy consumption which is why there’s a big movement to significantly reduce our reliance on fossil-based energy. This not only saves on earth’s natural resources but also lessens the pollutants we throw into the air and water.
Alternative Renewable Energy
There are different types of alternative energy including wind, hydrogen gas, tidal, biomass, biofuels, and solar. The best alternative energy available today is clearly solar power. A solar energy system is the most effective and practical way to renewable energy for most people. As long as there’s ample space to accommodate panels, anyone can utilize the sun’s powerful energy to produce electricity without adverse effects to the environment.
In actuality, a solar power system is really rather simple and involves only three or four parts: solar panels, inverter, mounts & peripherals, and battery (optional).
Solar Panels
The most notable part of an energy system is the solar panel(s), which is responsible for converting sunlight into electricity by what is called the photovoltaic effect. Utilizing Photovoltaic cell, aka solar cell, the energy of light (not the heat) from the sun is turned into direct current (DC) electricity. This solar irradiation process stimulates electrons to move through the solar cells.
There are different types of solar cell materials available including thin-film, monocrystalline, and polycrystalline[3] used in solar panels that vary in price, appearance, and cost. Each of these technologies have their advantages and disadvantages. In appearance, monocrystalline panels are black, polycrystalline have a blue hue, and a thin-film can be found in blue and black hues depending on the material they’re made from. For the most part, the type used in Southern California residential applications are the monocrystalline panels due to their higher efficiency, performance and attractive appearance.
| Solar panel Type | Advantages | Disadvantages |
| Monocrystalline | High efficiency/performanceAesthetics | Higher cost |
| Polycrystalline | Low cost | Lower efficiency/performance |
| Thin-film | Portable and flexibleLightweightAesthetics | Lowest efficiency/performance |
Today’s solar panel technology allows us to apply it on rooftops and/or on the ground where they’re most effective. It is imperative that solar panels are exposed to the sun for the longest part of the day and for us in California, application should be south-facing. The longest exposure and line-of-sight to the sun will in turn dictate where they’ll be installed on homes and businesses, while also avoiding other barriers that cause shading such as trees and buildings.
Inverters
The inverter is an essential part of the solar power system. This is the device that turns the direct current (DC) produced by solar panels into the practical form of alternating current (AC) electricity that we use in the United States at 110-120 Volts. Inverters are considered the work horse of the solar energy system and the first to likely have issues or fail. Inverters will usually have a shorter warranty compared to solar panels.
There are two types of inverters: string inverter and microinverter. A string inverter is usually mounted at a central location of a home, such as a wall inside or outside the garage, and it converts the direct current from the “string” of panels into alternating current. A potential drawback to a string inverter is the effect of a partially shaded panel lowering the performance of other panels since it is part of the string sequence. With a microinverter application, a small device is attached to each solar panel, allowing the conversion to work independently of each other. Microinverters are ideal in situations when shading is expected, but they do come with a higher price tag.
Mounts and Peripherals
Proper mounting is essential in the installation process of solar panels, not only to hold them down to the mounting surface but also for proper angling towards the sun’s rays. A reputable company will use high quality mounts/racks and peripherals that should last for the lifetime of the solar panels. Because of the size and weight of solar panels and the harsh outdoor environment all parts used for the installation should be strong and reliable.
Battery (optional)
Depending on the user’s requirements, a backup battery may or may not be necessary. The main purpose of a backup battery is to store the excess energy produced by the solar power system so it can be used later such as during nights, in bad weather, and in power outages. In most areas where homes are tied to the “grid,” a battery is often unnecessary. In this situation, excess power produced by a solar energy system is sent to the local utility company and claimed back as a form of exchange called net metering.
Those who prefer to be completely “off-grid” or wanting the assurance of always having power will need to install a backup battery system. The number of batteries required will depend on the individual’s consumption.
In general, batteries are normally the most expensive part of a solar energy system. There are different types of batteries available, and the most advanced and highest performing ones use lithium ion due to their fast response, charge and discharge speed, stability and longevity. However, in addition to higher prices, batteries usually have the shortest life span of all the solar components.
The goal
The objective of a solar power system is to utilize the vast energy of the sun to create your own power source, greatly reducing or virtually eliminating the need to purchase (in retail price) electricity from the local utility company. However, having a solar power system doesn’t mean you have endless energy for consumption. The size of the system you end up with is determined by the average amount of power use in a year, all measured in kilowatts (kW). As long as you stick to your normal usage, you will generally not have an additional bill from the utility company. But, if you do end up with one, it should be significantly less.
[1] Smithsonian magazine (https://www.smithsonianmag.com/sponsored/brief-history-solar-panels-180972006/#:~:text=Take%20a%20light%20step%20back,a%20thin%20layer%20of%20gold.)
[2] eia.gov – (Electricity Explained) https://www.eia.gov/energyexplained/electricity/how-electricity-is-generated.php#:~:text=Most%20of%20U.S.%20electricity%20generation,machine%20to%20drive%20electricity%20generators.&text=The%20fuels%20or%20energy%20sources,energy%2C%20and%20solar%20thermal%20energy.
[3] Energy.gov (https://www.energy.gov/eere/solar/articles/solar-photovoltaic-cell-basics)
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