With the development of the economy and the progress of society, people have put forward higher and higher requirements for energy, and the search for new energy has become an urgent issue facing mankind. Because solar power has the advantages of cleanliness, safety, and versatility, and adequacy of resources that are unmatched by thermal power, hydropower, and nuclear power, solar power is considered the most important energy source in the 21st century.
An off-grid solar system relies on energy from the sun to run homes, off-grid builds, or even recreational vehicles. Unlike grid-tied solar systems, batteries store any solar energy collected from panels in order to run some of, or your entire home. Off-grid solar system setups give you the freedom to live comfortably, and the option to run almost any appliance, rain or shine, morning or night.
Off-grid solar systems include 4 major components: solar panels, solar charge controller, solar battery, and solar inverter.
Solar panel is a device that converts sunlight into electricity by using photovoltaic (PV) cells. PV cells are made of materials that produce excited electrons when exposed to light. The electrons flow through a circuit and produce direct current (DC) electricity, which can be used to power various devices or be stored in batteries. Solar panels are also known as solar cell panels, solar electric panels, or PV modules.
Solar charge controllers are used in off-grid systems to maintain batteries at their highest state of charge without overcharging them to avoid gassing and battery damage. This helps to prolong battery life. Charge controllers also deliver proper current and voltage that meets the rated capacity of electrical loads. Without a charge controller connected to the PV array, the array would deliver too much power which would destroy the batteries and loads.
Solar charge controllers typically deploy either pulse width modulation (PWM) or maximum power point tracking (MPPT) technology to regulate and deliver the right amount of current and voltage from PV arrays to run electrical loads and safely charge batteries during the day. Then during the evening when there is no sunshine, the controller allows the battery bank to run the electrical loads. Solar controllers have electronic protections to protect against nighttime reverse current, short circuiting, high voltage, high temperatures, and battery reverse polarity. Additionally some controllers have low voltage disconnect capabilities and are equipped with LED warning lights to alert about installation errors and faults within the system.
Solar battery, also known as solar battery storage systems, work by storing the excess energy produced by solar panels (also referred to as solar PV panels) during the day, for later use when the sun isn’t shining. There are two main battery technologies currently used, lithium-ion and lead-acid, both of which are designed to handle the cyclic charging and discharging required for solar energy storage.
When sunlight hits a solar panel, the solar cells in the panel convert the sunlight into electrical energy in the form of direct current (DC). This DC electricity then flows to the inverter, which converts the DC into alternating current (AC) that can be used to power household appliances and devices. If the demand for electricity in your home is less than that being generated, then the DC can be taken from the solar panels and used to charge a battery.
During the night, when your home demands electricity your solar battery discharges to power your appliances and devices, so you’re reaping the benefits of solar PV long after the sun has set.
Solar inverter main function is to accept DC power input and turn it into AC power. They also act as the primary connection between the panels and the electrical distribution panel in the house. Modern inverters contain switches that can connect or isolate your solar energy system from the power grid and provide detailed information to your system’s monitoring equipment.