What are the components of a PV system? Go Back
Author: Marisan Hallett Date: 28 November 2022
From the sun to the solar cell, the solar cell to current, with words such as hybrid, and maximum power point, you may feel a bit lost when considering a PV system. The PV (photovoltaic) system consists of different components, each with a specific role, depending on the type of system:
1. PV module
The solar panel also called a PV module, consists of an assembly of PV cells. Most modules use wafer-based crystalline silicon cells or thin-film cells. These solar cells convert sunlight into electricity.
JA Solar JAM72S30-545/MR 545W PV Module
2. Inverter
Arrays (collection of PV modules) are connected to meet the voltage requirements of the inverter where electrical current is converted from direct current (DC) to alternating current (AC). The inverter samples the output power from the PV cell and applies proper resistance to obtain maximum power. Solar inverters also detect abnormal currents and grid outages protecting your PV panels from damage.
The maximum power point tracker (MPPT) increases energy produced per module. It monitors the direction of the sun and adjusts the module as needed for maximum exposure.
The four types of inverters:
String inverters are an older inverter technology. Unfortunately, because the panels are wired in series, should one panel’s output decrease, all the other panels’ output will also drop.
Micro inverters and power optimizers are attached to each panel to increase the system’s energy production. The power optimizers (DC power converters) assure individual panel monitoring, maximizing each panel’s output to a string inverter, where DC is converted to AC.
Hybrid inverters convert DC from your panels to AC, to power your home. It can also convert AC from the grid to DC to charge your battery. Hybrid inverters have different modes to provide power to essential appliances in your home in case of a blackout.
Off-grid inverters are designed to work without the grid. This means the inverter uses the energy generated by the PV modules and draws power from the battery. It converts DC directly to AC, to power your home.
3. Charge Controller
The charge controller regulates the amount of charge going into the battery from the system to keep it from overcharging. It regulates the power that is delivered to the load and excess power is delivered to the battery. The controller monitors the battery’s energy to ensure that the battery stays fully charged.
Victron PMP485027010 Easysolar 48/5000/70-100 Inverter/Charger combo
4. Combiner box
The PV array’s multiple strings have positive and negative leads. Positive leads are connected to fuses and the negative leads to a busbar in an enclosure. This is the source circuit. The multiple DC inputs from the panels are combined into a single parallel DC output in the combiner box.
5. Battery
The battery is used to store energy. Types of batteries available:
Lead acid batteries are a cost-effective storage option. These are reliable batteries and works great with off-grid PV systems and as emergency backup storage. Lithium-ion batteries have a long lifespan and does not require regular maintenance. These batteries have a higher depth of discharge meaning you can use more of the stored energy within the battery before it needs to recharge.
Other types of batteries are Nickel cadmium batteries and Flow batteries.
Freedom Won Lite Commercial 200/160HV Battery
6. Other Components
PV disconnect installed between the inverter load and the solar array. It serves as a safety measure by de-energising the array and isolating the inverter from the power source.
AC disconnect to isolate the inverter from the AC panel in a grid connected PV system.
Mounting to support the PV structure including brackets, rails, mid- and end clamps.
PV installations can be simple or complex. They range from small, rooftop mounted or building integrated systems to large scale utility power stations.
When purchasing components for your PV system, do your research. A Herholdt’s trusted installer will be able to source bankable products and install your system.
