When you think about electricity, you think about gird, but today in this blog we will be talking about a system that provides electricity without the involvement of gird. How? Simply with an off-grid solar system.

In this blog will aim to provide you with all necessary information about an off-grid system so that you can avail a booster of knowledge in simple terms. The basic question that haunts many is what is an

off-grid system and without a grid how can we have access to electricity? So let me start off by telling you what is an off-grid solar system?

An off-grid system is also known as a standalone PV system, where electricity is harnessed by solar panels and then stored inside a battery. This process is not connected to any grid and provides an independent power supply to your home/office, anywhere where you can use electricity.

Thinking about where to use an off-grid system?

Well, the most commonly used areas are where there is no grid available like remote faraway places, places with frequency power cut issues, remote/rural locations where access to the grid is difficult and costly.

Using electricity without grid-connected is confusing? Okay, so now let's talk about it’s working to give you a better picture.

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Working of an off-grid solar system.

As the system is not connected to the grid, the battery plays an important role in energy storage. The process goes as When the solar radiation fall on the solar panel it generates energy in the form of direct current (DC) which then goes to the charge controller that regulates the flow of charge and supplies the regulated power to the battery. In an off-grid system, battery is a showman that stores all the energy to supply power during the night or on non-sunny days. Like on

a sunny day when the solar panel is operating on full efficiently and produces enough power to feed the load and also to charge the battery, this charged battery is then used to power the load in the night or where the grid is not connected. The energy stored in the battery is in the direct current (DC) from, so this (DC) is converted into alternating current (ac) with the help of an inverter. This converted AC energy is supplied to the loads connected to power the load with energy. And dim, your place is all light up!

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On the basis of its energy form, There are typically five types of off-grid solar systems, which you can choose according to the useage of power.

1. DC ONLY SYSTEM

This system is perfect to use on dc-powered appliances having 12 voltages or lower and is mainly designed to power low energy consuming devices. Here there is no solar inverter as DC power is directly fed to the appliances and no backup generator.

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2. AC only system

This system is designed to handle bigger loads and is equipped with a solar array. Here there is an inverter that converts the DC power into ac power that can be used to run your all household appliances. The backup generator is absent, so do ensure that your system can handle your loads in case of power outages and emergencies.

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3. Mixed DC and AC system.

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This is designed for powering light or low energy equipment, kind of similar to DC only system but have the addition of an ac inverter with no backup generator

4. AC system with backup generator

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Same as ac system but with back up generator. Generator is adding advantage for proving continuous power even during emergencies or power outages.

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5. AC system with wind and solar

This system run on both source of energy, solar and wind energies. During sunny days it works on solar and if there is cloudy and windy outside, wind energy is collected via wind turbine.

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The basic components of an off-grid system

1. Solar panels- (link)
2. Charge Controller

This component is necessary to regulate the current going to the batteries from the solar panels. They maintain batteries at a high state of charge without overcharging them.

3. Battery bank

This is used to store the excess solar power that’s generated beyond the needs of your appliances.

4. Generator (optional)

This is for backup purposes, just in case your batteries malfunction or there’s an overcast and your batteries are drained.

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5. Solar Inverter (AC)
   

Converting the DC power into AC power

A solar inverter is perhaps the most important component in the off-grid system. There are 3 types of inverters available in the market to choose from depending on the output waveform. What to choose is your next big question? Then read further to know the answer

1. Modified sine wave inverter

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This inverter is less expensive and has a time interval between the maximum positive and maximum negative points also called as a modified square wave inverter. You can not use this in an inductive load as it causes excessive heating that can affect the durability of the appliances. On the beneficial side of it, low-cost one can use it for

small devices.

2. Pure sine wave inverter
   

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Pure sine wave comes with a stable sin wave output and is also called a true value inverter. It is a good choice for sensitive electronic appliances. Further, it is classified on the basis of its frequency.

Low frequency; These inverters generate a high starting current, so it is more beneficial for compressors and air-conditioners that can be used for long run time.

High frequency: These inverters are free from electromagnetic effects and offer a higher power conversion rate with an ability to run both inductive as well as a resistive load. They are reliable and efficient with minimum losses.

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3. Square wave inverter;

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these inverters are not currently in use due to their instability and harmonic distortion. They generate poor quality unstable square wave ac output that can affect the durability of the inverter and also

So out of the mentioned 3 inverters, two inverters that you can buy is pure and modified sine wave inverter. The below table will help you to make your firm choice as to what to get.

Now you know what to choose and why.

The last thing to get into is the allover advantages and disadvantages of the system

Advantages:

• It is independent of a grid
• Easy to install in any remote area
• Output voltage can be regulated
• No need of synchronisation of frequency and voltage between grid and inverter

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Disadvantages

• Limited backup hours
• Complex to installed

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