Most DC-coupled off-grid solar system includes four basic components: solar panels, a controller for charging the batteries, an inverter, and the battery bank. In this post, we’ll focus on the four most important components of a solar system: the panels, the batteries, and the solar concentrator.
The solar panels themselves are the most readily apparent component of an off-grid solar system. 60, 72, 120, 132, or 144-cell solar panels are now the most cost-effective. All of the panels are made up of solar cells, which are the tiny squares that cover the surface. Monocrystalline panels have become the industry standard in most systems today.
Why choose monocrystalline ones?
It ultimately boils down to two factors: availability and price. Most of the time monocrystalline panels are utilized in off-grid solar systems as the industry has transitioned to creating cost-effective monocrystalline modules. Polycrystalline panels had an early edge since they were less expensive to produce. There is no longer a real advantage to utilizing polycrystalline now that monocrystalline has become the norm, is more efficient, and is more inexpensive.
Solar panels are connected to a charge controller, which controls the flow of electricity from them to the battery bank. To ensure the battery bank lasts as long as possible, charge controllers monitor and prevent overcharging. Generally speaking, charge controllers can be divided into two categories: MPPT (Maximum Power Point Tracking) and PWM (Pulse Width Modulation).
Since the input voltage from the solar panels must be 30 percent greater than the battery voltage before using an MPPT charge controller (up to the charge controller’s limit), it is less important which voltage of the solar panel is utilized in the system.
An inverter would be the next component in an off-grid solar system design. Almost all battery-based inverters are used in off-grid solar installations. With the inverter, you may use the battery bank’s DC electricity to power your loads in the same way you would if you were plugging into an AC outlet at home, by converting it to usable AC power.
Depending on the off-grid load, inverters exist in various sizes that can accommodate smaller or higher loads. Another issue is to make sure the inverter can manage all of the loads in the system at once.
The inverter battery bank is the final major part of the solar system, and it is both an important factor and a costly one. Lead-acid and lithium are the two most prevalent battery chemistries in the solar power sector.
In the solar power business, lithium iron phosphate (LiFePO4) is the most used chemical for lithium batteries. As well as in terms of size/weight and charging/discharging capabilities, lithium batteries differ greatly from both flooded lead-acid and AGM batteries.
Lithium Iron Phosphate is a chemical that can be safely stored without the requirement for ventilation because it emits no fumes. Unlike lead-acid batteries, lithium batteries do not need to be fully charged and do not require any further maintenance.
Additionally, the chemistry of LiFePO4 is optimized for a large number of charging cycles. When it comes to off-grid solar applications, lithium batteries have several distinct advantages.
Lithium batteries have a built-in battery management system (BMS), which provides an additional benefit (battery management system). The battery’s health is always being monitored by the BMS. For example, an overcharged battery will be forced to shut down by the BMS, as will a battery that is too hot or too cold due to a parameter violation.
To put it another way, the BMS acts as a layer of defense for the batteries, making it nearly impossible to harm them.