Solar System Components

If you are browsing solar panels you may have come across the terms Monocrystalline and Polycrystalline solar panels. So, what do those terms mean? Monocrystalline and polycrystalline describe the manufacturing process of solar panels.

Monocrystalline solar panels use solar cells made from a single silicon crystal.

Polycrystalline solar panels use solar cells made from multiple silicon crystals.

Monocrystalline panels are more efficient because the cell uses one crystal vs several crystals. Mono panels used to be more expensive because the manufacturing process was more complex; however, that is no longer true. Solar panel manufacturers have geared their production lines to mono panels because of the increased efficiency. You can tell the difference between mono and poly panels by the color. Poly panels have a blue hue, while the mono panels are all black.

Your solar panels will need a system to attach them to your roof or to hold on a ground mount. Solar panels perform best when they are perpendicular to the sun’s rays. Since this angle constantly changes, we usually mount our panels facing south since we are in the northern hemisphere. Solar Panel mounting is the only one of the solar system components that we manufacture in-house here at Belmont Solar. We build Tough Trac, a solar panel racking system that integrates wire management into the rails. This system also features adjustable L foot mounts, allowing the system to account for uneven or bowed rafters. As the mounting system is designed for strength this system allows for fewer roof penetrations than other mounting systems. This makes our in-house developed mounting system unique, check out our Tough Trac page to learn more about the system.

Solar panels create DC power, but our houses run off of AC. The inverter turns the DC power to AC and sends the current to your electrical panel. Inverters also route power between solar system components, allowing you to monitor performance and track your savings. Depending on the situation, we use Sol Ark, Solar Edge, and Tesla inverters, all of which allow you to monitor the system performance with an app or on your computer.

An energy storage system is one of the essential solar system components for off-grid systems and is also used to create hybrid solar systems. A battery bank on a hybrid system allows you to use the energy created during the day to reduce your energy consumption at night and help run essential appliances during a power outage. Three main types of batteries are used for battery backup systems: flooded lead-acid, sealed lead-acid, and lithium batteries. Let’s look at the pros and cons of each type.

Flooded lead-acid batteries have liquid electrolytes, which can be accessed by removing the caps. Flooded lead-acid batteries are the oldest battery design and are not the best choice for a battery backup. FLA batteries are prone to failure when not maintained. You must maintain the batteries each month, which must be refilled with distilled water. Flooded lead-acid batteries are cheap, but there are much better options.

Sealed lead-acid batteries are sealed with the electrolyte inside. They do not need to be refilled and do not emit toxic fumes. They have fewer maintenance requirements than a flooded lead battery but are still old technology. You must use a float charge since overcharging the battery will break down the water and cause premature aging. Undercharging the battery will cause lead sulfate to remain on the electrodes, reducing the charge. If the batteries are discharged for too long, the battery will not be able to recover and will need to be replaced. SLA batteries are better than flooded lead acid batteries but still have quirks.

Lithium batteries are more expensive, but their advantages over lead batteries make lithium the best choice. Lithium batteries have a higher energy density than lead batteries, allowing you to store more energy in less space. Because you store more energy, you can use more energy to reduce your reliability on the grid. The depth of discharge is another critical area where lithium batteries shine. Lead batteries should not discharge past 50 percent since it will negatively affect the battery life. It is normal to use 85 percent of the charge each cycle in a lithium battery, giving lithium a higher effective capacity than all lead batteries. Lastly, studies have shown that lithium batteries can last 20 years depending on use. Lead Acid batteries will only last around 8 years. We only install lithium batteries when installing off-grid and hybrid residential solar systems. We are a Tesla Powerwall installer and install Rubix batteries. In 2024, Tesla is launching the Powerwall 3, which will integrate an inverter into the powerwall. The Powerwall has a 13.5 capacity, however, Rubix batteries are modular, allowing you to stack them like blocks. Each module has a 5.0 KWH capacity, giving you a range of 5.0 to 30 KWH per stack. If you want to expand your system, add another module.

Tesla’s Powerwall and the Rubix batteries can be monitored via an app that is supplied by the inverter. Tesla’s app can be downloaded from Google or Apple to monitor day-to-day operations. Rubix batteries have a communication cable that connects to your Sol Ark inverter. You can monitor the system operations and performance using Sol-Ark’s app.