Step 2: Collect The Sun's Rays With Photovoltaic Cells
What Are Photovoltaic Cells?
A photovoltaic cell is a form of technology that converts solar energy into electricity using the photovoltaic effect. It is comprised of several layers, the most important is the semiconductor layer.
The semiconductor layer is comprised of two distinct layers (P-type and N-type) and the semiconductor layer is what does the work of converting the visible light of the sun’s rays into useful electricity.
The semiconductor is layered with conducting material on both sides. This conducting material collects the electricity produced by the semiconductor.
The final layer is the anti-reflective layer. This is applied to the sun facing side of the solar cell. As all semiconductors are naturally reflective, energy lost from reflection can be significant. To prevent reflected energy being lost the anti-reflective coating is applied like coatings used on eyeglasses and cameras.
Poly Versus Mono Crystalline Architecture
Monocrystalline solar panels are produced from one large silicon block and are produced in wafers. They are made by cutting individual wafers of silicon that can be affixed to a solar panel. Monocrystalline cells are more efficient than poly and amorphous solar cells. Monocrystalline wafers are more labor intensive to manufacture, and as such can be more expensive.
Polycrystalline cells are also made from silicon, but they are made by fusing multiple silicon crystals together into a large block. The silicon molecules are melted then re-fused together into the panel directly. Polycrystalline cells are less efficient than monocrystalline, but more cost effective. The polycrystalline cells have a blue hue.
Why Do Houses Use AC?
AC electricity is used in most electrical distribution systems such as the power grid for many reasons, but the most important one is the ease at which AC electricity can be transformed from one voltage to another. AC power has the advantage of low energy loss during any voltage transformations that may take place, allowing you to maximize the energy received from your home solar panel system.
Converting Solar Power To Usable Energy
How Do You Convert DC-AC
DC energy is converted to AC energy by using electronic components and capacitors to alternate the flow of electricity gradually in both directions. The alternating in flow directions of power make the DC energy into usable AC power in your home.
Where Does The Energy Go Once It Is Inverted?
Once the home solar panel system inverter has done its job and converted the DC power from your solar panels into AC power, it is ready for your home to use. In most home solar installations this energy will be made available at your breaker box for your home to pull from. If you have a battery backup system installed, some of the excess electricity generated from your solar panel system is used to charge the batteries.
String Inverter Versus Micro-inverter
Micro-inverters allow all the cells of the solar panel to gather energy individually. The advantage to micro-inverters is that if one cell or cell block is obstructed by a leaf or other lawn debris, the remaining unaffected panels can still perform at their optimum capacity.
String inverters can only perform as well as the lowest performing panel in a system. In the case of string inverters, if there is a leaf or other obstruction of a solar panel on your roof, the string inverter will only be able to perform as well as the lowest performing panel in the system. This means you could lose a lot of your potential energy generation and savings from your home solar panel system.
Step 4: Converted Electricity Gets Used
Your Home Gets Power First
Once the AC power from your inverter is ready to be used, it passes through your home’s breaker box. This allows your home and appliances the opportunity to use the solar power generated energy first. Any excess power generated is then passed to your battery backup system if you have one installed, and on to the grid via net metering for credits on your energy bill.
What Happens To The Extra Energy Your System Produces?
Battery Storage Charging
Battery backup systems will charge up using the excess electricity being generated by your home solar panel system during peak hours. This energy is stored and can be used later during low production times like at night or during overcast days. This stored power in your battery backup system can also be used in the event of a power grid outage, keeping your home powered even while your neighbors are without power.
Net Metering
Net metering is what we call the process of allowing power from your electric meter on your home to flow in both directions. This process allows you to send unused solar power energy generated to the electrical grid for a credit on your energy bill from the power company. This same process allows you to continue to pull energy from the electrical grid during periods when your home solar panel system may not be able to generate enough power for your needs, using the credits that you’ve generated first, to help keep your utility bill as low as possible.
Solar Panel F.A.Q.
Solar panels require sunlight to produce energy. Due to this requirement solar panels do not work at night. At night and during low production times for your home solar panel system, net metering and battery backups instead help to provide your home with power.
The photovoltaic cells in your home solar panels can use direct or indirect sunlight to generate power. During cloudy or overcast days, your panels will still work by absorbing the sunlight that is reflected off the clouds or manages to pass by the clouds completely. Though your system will still collect solar power it will not generate as much during these weather conditions.
Your home solar panels can gather the sun’s rays even during rain. As the rain and clouds do not absorb 100% of the sun’s rays, the remaining sunlight that is reflected or passed through can still be absorbed and converted by your home solar panel system. Rain can also help improve your system performance by cleaning away any dust or dirt that may have accumulated on the panels.
Solar panels do work during the winter months. During winter months your home solar panel system will still collect and convert the sun’s rays into energy for your home. Winter electricity production is lower during winter months though due to shorter days than during peak mid-summer. Your solar panels can even work during the snowy months, though the panels will not generate electricity if they are blanketed with snow. Due to the angle, ability to absorb the suns heat, and placement of the panels to have the most sun during any given day, solar panels will tend to shed any accumulated snow rather quickly.
The answer is yes, if you have a battery backup system installed as well. During periods when the power grid is out, your solar system will continue to generate power, but your home has nowhere to store it to be used without a battery backup system. For this reason, we highly recommend investing in a home solar panel system battery backup. The battery backup can continue collecting energy for you to use later in your home even when the grid is out, keeping your home comfortable and allowing appliances like your refrigerator to continue running, even preventing food from spoiling in the case of a long grid power outage.
During low production times such as at night or during extremely overcast days a battery backup system can keep your home powered without relying on the grid. Battery backup systems are a great way to maximize the savings of your home solar panel system. Most homes that have solar panel systems installed are on a net metering grid. This means that excess produced energy is sent to the grid for a credit on your energy bill. In reverse, during periods when your solar panel system is not generating enough power for your home, you can then in turn use those energy credits to buy back power from the grid. With a battery backup system, you limit how often and how much power you need to pull from the grid during these low production hours, increasing the savings generated by your excess solar credits.