By Mirela Niculae
For many homeowners who want to lower their carbon footprint, switching to solar energy is a no-brainer. But while some people are familiar with how solar panels work, many are not aware of the roles played by supporting pieces of the solar system.
Below is a breakdown of a standard solar system and how each piece works to create energy for your home.
Photovoltaic (PV) panels
Everything starts with the solar panels. Each panel is comprised of silicon solar cells, interconnected with each other using conductors at their positive and negative poles. When photons from sunlight are absorbed by the solar cells, the electrons will be knocked loose from their atoms and then conducted (using the solar cell structure) through the panel, generating electricity.
Solar panels should be placed in an area where they will receive the maximum amount of sunlight, which is why the roof is the ideal place for them. However, not all roofs are oriented for solar energy, which is why you may need to purchase a rack that allows the panels to move according to the sun’s position. If your roof receives a lot of direct sunlight, you’ll only have to buy a fixed mount, which will save some money. If the roof is not a good option, you may have to sacrifice a piece of your property so the panels can be installed on the ground.
Proper mounting racks can make the difference between a highly efficient solar system and one that’s less productive. Racks are also important for the safety of your panels.
First, a mounting rack must be solid and stable so it can support the solar module or array all year long. This means protecting the panels against the wind, rain, snow or even earthquakes.
Homeowners have the choice between fixed mounts, which are generally used on roofs. Fixed racks secure the solar panels to the roof, not allowing them to move. The other option is a tracking mount; primarily used for ground panels, tracking mounts automatically adjust your solar panel to the optimum angle for sunlight absorbtion.
In terms of material, producers tend to use several options such as aluminum, stainless steel, wood, plastic or iron. Aluminum and stainless steel are often the best options because they’re lightweight, corrosion-resistant and strong, but this may vary depending on the project.
DC to AC power inverter
The inverter is an essential part of the solar system. Its role is to transform the direct current (DC) produced by your solar panels into the alternative current (AC) that powers your home.
Standard inverters, known as string inverters or centralized inverters, service an entire string of panels, meaning your solar system is only as powerful as its lowest-performing panel.
Alternatively, a more efficient – albeit more expensive – option is the Module-Level Power Electronics (MLPEs), also known as a centralized inverter or micro-inverters. With this type of system, each panel has its own inverter. As a result, the array of panels can work at optimum capacity even when one of the panels doesn’t work at full power. With a string inverter, if one panel is in the shade or the surface is dirty, the entire production of energy suffers. With micro-inverters, the problem panels will produce less energy, but the rest will work as expected.
If your solar system is connected to the local energy grid, the excess solar energy your system produces will go into the grid. In exchange, you will receive a credit on your utility bill.
Your net meter is used to measure how much energy your system is producing and how much energy is being sent to the grid. If your system is powerful enough to sustain the house all year round, you won’t have to worry about paying any electricity bills, but if you do need the grid, your bills will still be significantly lower than if you didn’t use solar.
If your solar system is not connected to the energy grid, a battery will act as a backup power source should your system produce less energy than expected. With this system, the energy stored in the batteries during the day can be used at nighttime. However, batteries are still quite expensive and require storage space themselves.
As you can see, a solar system is not extremely complex and each piece has its logical place in the hierarchy. As long as it is properly installed and the panels have enough sunlight, this is a highly rewarding investment, both environmentally and financially.