How do Solar Generators Work?
A solar generator works by converting sunlight into DC electricity, which is then stored in a battery and/or converted into AC power to be used for operating electrical appliances. A solar generator is mainly made of solar panels, a charge controller, a battery, and an inverter. Solar generators are available as assembled units. You can, however, purchase the individual components mentioned above to build one yourself.
Solar generators are mostly portable units that can be carried along in vehicles and set up in camping locations. They are also used as backup generators in the event of a power outage. Solar generators are rapidly replacing gasoline and diesel-powered generators, which makes it possible to generate emission-free power without any recurring costs.
Understanding a Solar Generator
As mentioned before, a solar generator converts clean energy from the sun into electric current – which is one of the significant advantages of solar energy. The amount of power generated depends on the size of the solar panels. Understanding how a solar generator works requires an understanding of each component and how it works.
Some people also construct their own solar portable generators using a general guide to solar or a specific sizing guide for a home solar generator. Nowadays, solar companies offer several options of solar power generators with multiple components integrated inside a single unit.
While new and renewable energy technologies such as a solar wall or a solar roof are slowly becoming common, traditional solar applications like these will never go away. Some effective solar + gasoline hybrid energy generators are also available, but we won’t cover them here.
Let’s look at the components of a solar energy generator and their functions in a little more detail.
Components of a Solar Generator
Any generator solar power will use the following components:
Solar panels – the power source – are the most important component of the generator. Made from semiconductor materials such as silicon, the solar photovoltaic cells in the panels produce a current by harnessing the sun’s radiating energy. The electrons in these photovoltaic cells are knocked off their orbits by photons from the sun. These electrons flow in a circuit, thus resulting in electricity production.
Solar panels can come in a large variety of sizes. Most solar generators usually employ 100 or 200 watt solar panels, which helps keep the generator portable.
Since solar energy only works during the day, having energy storage helps. Batteries thus become the energy source in hours of darkness or cloudy days. As an important piece of solar equipment, batteries convert electrical energy from the panels into chemical energy. This chemical energy is again converted into electrical energy when needed.
Batteries usually come with a 12V voltage rating. The solar panels used in generators are normally rated to power 12V batteries (i.e. around 18V). Batteries usually come in two types – lead-acid and lithium-ion.
A charge controller helps modify the current coming from the solar panel to make it more uniform and safer for the battery. At their peak capacity, solar panels generate about 18V. At such times, the charge controller brings this voltage down to 15V so the 12V battery can be charged smoothly. This improves battery performance and lifespan.
Charge controllers prevent overcharging the battery. They also prevent reverse current flow from the battery to the panel, avoiding damage to the energy generator’s panel. These are normally small units which often come integrated in a solar generator.
The inverter is sometimes called the second most important component of any solar system. Sometimes even dubbed as the ‘heart’ of the system, its function is to convert direct current from the panels or the battery into alternating current.
AC power is the most used type of energy worldwide. It is easier to transport power to farther distances without significant losses. All the big or small appliances we use daily are suited to utilize AC power.
Solar power makes it possible to eliminate the need of AC, as transmission to long distances is no longer in question. Therefore, there are a few appliances in the market that work on DC directly, such as some LED lights and fans. Solar energy generators often have DC ports to operate DC appliances directly.
However, when having to use more complex appliances like laptops, it makes sense just to use an additional device to convert the DC power to AC – hence the need of an inverter.
Step-by-step Working of a Solar Generator
Now that we are versed in the components and their functions, it will be easier to understand how the solar generator works.
- When the panels are connected to the battery unit (via charge controller), and exposed to sunlight, they start generating DC power that flows to the charge controller. Depending on the intensity of sunlight and panel surface (clean and scratch-free is the best), the voltage generated can be anywhere between 12V and 18V.
- If the incoming voltage is more than 12-13V, the charge controller will pass this power to the battery. It will first convert this variable DC power into more constant DC power. When the battery is full, the charge controller will automatically stop power transfer from the energy source.
- Current coming from the charge controller will create a chemical reaction inside the battery, where the product is energy being stored as potential chemical energy. When any load is connected to the battery, a reverse chemical reaction allows the conversion of this potential chemical energy back to electrical energy. The current going out from the battery is still direct current, and if the electrical load in question is suited for AC, an inverter is needed in the setup.
- If the appliances you are trying to run using the solar generator are suited for direct current and are rated for 12V current, they can be directly connected to the battery/panel. This is one of the advantages of solar energy. Portable generators usually come with posts for 12V DC output, which can be used for DC loads. However, if the appliances support only AC input, the power is sent further for conversion to an inverter.
- For AC supporting appliances such as laptops carried on a camping trip, an inverter modifies the 12V DC power coming from the battery. This power is converted to 110-120V AC, like an outlet plug in homes. Any portable solar generator comes with a similar output plug on its casing that reads 120V AC. Appliances such as laptops or mini refrigerators can be directly powered through this plug, just like in a home. Allowing AC appliances to be operated makes solar generators as good as backup generators in terms of versatility.
As the solar industry advances with technology, solar power generators will become smaller, lighter, simpler to use, and cheaper, as the solar panel cost keeps dropping. While choosing among solar powered generators, it is important to select one that suits your needs in terms of size and capacity while choosing a reliable brand with a long solar panel lifespan. Finally, make sure you go through some trustworthy solar generator reviews before making a decision.