Solar Components

Understanding the products or components that enable a solar energy system to function properly is important. Any potential solar power system owner should take the time to understand what summarizes a photovoltaic array and how those components work to enable electrical generation for the energy needs.

It is important to remember that each system is unique in its size and structure, therefore application of a photovoltaic array will differ from another.

A Solar Energy System is a renewable energy generating system that collects photovoltaic energy from the sun and converts it into usable electricity. Often found as roof-top PV arrays, these systems can range in size and are able to power different types of properties - such as residential, commercial, and utility-scale zones.

Photovoltaic systems can be used in multiple applications: standard arrays such as roof-top or ground mount serve to generate energy for a residence or building, while other non-traditional systems can be utilized to power other objects or function (such as space satellites, hand-held calculators or vehicles).

Standard residential or commercial solar power systems consist of a core set of components - (Solar Panels, Inverters, DC/AC Disconnects, Meters, Wiring, Racking and Mounting), these are usually grid-tied. Some systems require additional components added to the core set to function – (Charge Controllers, Batteries, Additional Balance of Systems items and more), these are usually off-grid.

Solar Panels or PV modules are the most commonly known component in a photovoltaic array. Made up of mostly solar cells, framing, and glass; solar panels work by collecting and harnessing photovoltaic energy from the sun, and delivering that energy as ‘direct current’ (DC) power to an inverter or converter component (may be a charge controller in some instances).

The DC power generated by a solar module is an electric current that flows in a constant direction. This type of power is generally not readily useable for standard electric demands, and must be translated into ‘alternating current’ (AC) power before it can be used for standard electric devices inside a home or building.

Solar Panels consist of two most well-known types of solar cells, Polycrystalline and Monocrystalline. The difference consists of how silicon crystals in the ingots or wafers are harvested, developed and formed, each creating a different look and color to their appearance. Both types of PV cells are known to be effective in their general ability to produce solar electricity.

Inverters come in different types of sizes and use various technologies to enable efficiency in the function to produce AC power. The most common inverters are; String Inverters, Central Inverters, Microinverters, and Battery-based Inverters. Each will carry different mechanical and technical characteristics.

String Inverters can be wired for a row of solar panels to connect to one of several strings inside the inverter to accommodate a series of modules, while Microinverters are generally mounted to the back of each panel or (every other panel), to convert energy per module into AC power. Each type of inverter is not necessarily better than another as each one has its benefits and drawbacks, and their technologies are specifically used for application purposes in certain circumstances.

*In addition to Microinverter technology, PV Optimizers are applied similarly to the back of each Solar Module, and connect directly to a concurrent Inverter – which helps maximize yields drawn for the solar panels.

Monitoring technology is able to display information ranging from energy generated by the solar panels, to real-time data, to immediate fault detection and troubleshooting, to energy yield data over a set amount of time. A comprehensive Monitoring system can benefit the system operator to better understand the way the solar energy system is operating, (and measures that can be taken to better increase yields, productivity, maintenance and other variables) in real time or over the course of the systems lifespan.

Most racking systems will use a combination of: Rails, Flashings, Lugs, Mounting Brackets, Wire Clips, Splice Kits, Braces, End Caps, Attachments, Tilt Legs - and other components to complete a full racking and mounting system. Ground mount systems will require concrete and steel piping in addition to a complete racking kit to be placed onto land.

Racking and Mounting is an essential part of any solar energy system. Both roof-top and ground mount arrays need to be set atop a sound and reliable structure to ensure the system can maintain integrity and operate for an extended period of time.

Commonly, most items that make up Balance of Systems products include: DC/AC Disconnects, Junction Boxes, Combiner Boxes, Circuit Breakers, Fuses, Load Centers, Rapid Shutdowns, Surge Devices, among other components that may vary from system to system. These components will differ per individual solar energy system, as some systems will need more or less power control and distribution depending on their application.

Every photovoltaic array needs a series of safeguards and power control options to be available at any time - whether it be for the safety or integrity of the system, or to enable emergency maintenance in case of a fire or other potential issue that may arise. Power Control is necessary in any electric generating system.

Wires will generally be made of aluminum or copper, be solid or standard, are insulated, and meant to either pass through DC current or AC current depending on where they are positioned and connected. Wires will also be color coded for safety and identification purposes by a system operator or inspector who needs to understand which wire controls a certain current, (Positive, Negative, Grounded, etc.)

Standard systems will utilize wires which can hold and pass through certain voltages and wire gauges depending on the PV array setup. These values are commonly dependent upon the voltage of the system and its concurring components used within the interconnected stream of items.

Charge Controllers come with various types of sizes and technologies that enable generally an off-grid (Battery Bank) system to function properly. These two types of technologies are MPPT (Maximum Power Point Tracking) and PWM (Pulse Width Modulation). Charge Controllers are often used within an off-grid or hybrid with battery back-up solar energy system.

A series of Charge Controllers are important for maintaining battery integrity with a system that utilizes them. Due to the sensitive nature of power storage components, it is vital to regulate their ongoing activity to derive the maximum lifespan possible, and helping to reduce future maintenance costs and upkeep.

Off-grid and hybrid systems will often utilize a Battery, (or series of Batteries), to store collected energy delivered by a Charge Controller, Inverter or both – then making the resulting energy ready for withdrawal on demand when a system operator requires it.

Batteries will utilize different types of technologies and materials to enable power storage capability. Usually there are four types of Batteries; AGM, GEL, Flooded, and Lithium Ion – each type uses different fluids and acids that can hold on to energy for an extended period, with slow power depletion.

Each type of Battery will require different amounts of maintenance per technology, and expected lifespans for each technology will be influenced from how a system operator charges, stores, and takes power from the Batteries.