A solar generator is a system that captures sunlight through solar panels, converts it to electrical energy, stores it in batteries for later use, and provides a means to use that stored energy for powering electrical devices.
Here’s a breakdown of the four primary components and their functions in a portable solar generator:
Solar Panels
Solar cells, primarily made from silicon, exhibit conductive properties.
When exposed to light, the electrical characteristics of silicon alter, producing an electric current.
A cell comprises a small silicon square (around 6” x 6”) with electrical contact plates on its face.
Solar panels are constructed by arranging a grid of these cells on a protective back sheet and covering them with glass on the front.
Solar panels come in three main types: monocrystalline, polycrystalline, and thin-film, each with its unique attributes and efficiency levels.
To power a typical home or office, multiple panels are required. In a solar panel system, a collection of panels is termed an array.
Solar panels connected to the same inverter are collectively referred to as a string of panels. (Inverters have a maximum string size, indicating the upper limit of panels they can support.)
For instance, a system may have two inverters, each supporting a string of 10 panels, culminating in a 20-panel array.
Manufacturers often provide a warranty guaranteeing their panels will retain at least 80% efficiency for 25 years.
Post-warranty, the panels don’t cease functioning; they operate at a diminished output.
For example, a 300-watt rated panel would still deliver 240 watts of output at the 25-year point.
Panels have shown remarkable reliability.
A study by the National Renewable Energy Laboratory (NREL) revealed that over 75% of panels surpassed their warranty performance.
P-type and N-type Solar Panels:
These terms p-type and n-type refer to the doping process of silicon which creates a material that can either accept or donate free electrons – a crucial aspect for solar electricity generation.
- P-type (Positive-type) Silicon: Doped with boron, creating “holes” that accept electrons.
- N-type (Negative-type) Silicon: Doped with phosphorus, contributing extra electrons.
Charge Controller
Charge controllers are vital in battery-based renewable energy systems, acting as a regulator to prevent battery overcharging, thus ensuring the longevity of deep-cycle batteries.
They serve as a strict intermediary between solar panels and batteries, halting power delivery once a full charge is achieved to avoid battery damage and potential hazards.
This is crucial as most 12-volt solar panels have an output ranging from 16 to 20 volts, while 12-volt solar batteries require 14-14.5 volts for a full charge, showcasing the ease of overcharging.
Understanding the basics of a charge controller is beneficial, regardless of a DIY or professional solar installation.
The fundamental roles of a controller include blocking reverse current, preventing overcharge, and sometimes averting battery over-discharge, electrical overload protection, along displaying battery status and power flow.
Modern solar charge controllers monitor the battery’s voltage level and regulate current flow from panels to the battery.
They optimize battery charging in three stages: initially maximizing current to charge the battery swiftly up to about 80% (bulk charging stage), then reducing the current as the battery nears full charge (absorb stage), and lastly, maintaining a float or trickle charge to keep the battery fully charged and ready for use.
Batteries
Without a storage solution for the energy harnessed by your solar generators, solar power could be rather inefficient—your appliances would only function when the sun is shining, and any unused energy would be wasted, leaving you powerless at night.
This is where solar batteries step in, storing the energy generated by your solar generators for use when required.
They offer an alternative or an addition to sending energy back to the grid, aiding in making your home or facility more resilient to power outages, and potentially enabling a complete off-grid setup.
Solar batteries are pivotal in realizing the full promise of renewable energy.
They capture and store any surplus energy generated during sunny intervals, ensuring a steady power supply throughout the year.
As solar panels convert sunlight into electricity, the excess energy is stored within these batteries for later use.
Within the solar battery, chemical reactions occur to hold the extra electricity as potential energy.
So, when the sun isn’t shining, like during the night or on cloudy days, the stored energy is converted back into usable electricity and supplied to your home.
Solar batteries empower homeowners to optimize their solar energy usage, enhancing the reliability of solar power systems while reducing reliance on the traditional power grid.
With the capacity to store and utilize solar energy even during sunlight-scarce periods, solar power becomes a more viable and efficient renewable energy choice.
There are four types of batteries used in the world of solar power: lead-acid, lithium ion, nickel cadmium, and flow batteries.
Lead-acid batteries typically last between 3-7 years based on maintenance, while premium lithium batteries come with a 10-15 year warranty.
Inverter
A solar inverter plays a pivotal role in a solar power system, acting as a bridge between the solar panels and the electricity that powers your home or workplace.
It essentially translates the energy harvested by the solar panels into a format that your appliances can utilize.
Here’s how it works: Solar panels absorb sunlight and produce a type of electricity known as direct current (DC).
However, the appliances in your home require alternating current (AC), which has a different electrical waveform.
This is where the solar inverter comes into play.
It takes the DC output from your solar panels and transforms it into the 120V/240V AC output that your appliances need.
Let’s delve a bit deeper into the process.
The sunlight hits your solar panels, which consist of photovoltaic (PV) cells made from semiconductor materials like crystalline silicon or gallium arsenide.
These PV cells have layers with different electrical properties, creating a junction where the magic happens.
When sunlight energy hits these layers, it excites the electrons, causing them to move and create an electric current—this is DC electricity.
Now, this DC electricity can either be stored in a battery for later use or sent straight to the solar inverter, depending on your solar system setup.
Once the DC electricity reaches the inverter, it’s time to make it usable for your home.
The inverter processes the DC electricity, changing its waveform using a transformer.
This transformation involves a clever use of electronics, employing transistors that switch on and off at high speeds, effectively mimicking the waveform of AC electricity and tricking the transformer to output AC electricity.
In essence, the solar inverter performs a kind of electrical alchemy, taking the raw energy harvested by your solar panels and refining it into the electricity that keeps your home humming along.
Solar inverters usually come with a 10-20-year warranty, implying a replacement once or twice during the system’s lifespan.
