How an off-grid Solar power inverter system works

Posted by Felix Okoli on Wednesday October 21, 2015 at 17:0:55:

An off-grid Solar power system is an electric power system in which the main power is supplied by the sun to the batteries connected to the inverter. Unlike an on-grid Solar power system, it doesn't make use of power from the grid or power company and in this way, reduces your bills and makes you less reliant on the power company. It's an independent power generation system that is eco-friendly since it only depends n the Sun.

An off-grid Solar power inverter system makes use of solar panels, a conducting wire, a charger controller, an inverter and deep cycle batteries only to provide power to your electrical devices. It can come with easy to install instructions or you can just get a technician setup one for you.

Sunlight is converted to electricity through the means of photo-voltaic(light sensitive) cells. When sunlight falls on certain elements, they naturally tend to give up electrons and hence produces electricity which can be transmitted from one spot to another. That is basically how electricity is generated from the sun. It requires sunlight and a material whose ions gain energy to produce electricity when it comes in contact with light. In this case, Solar panels are the materials specially designed to produce electrical energy when they get sunlight and this electricity is supplied to your inverter and batteries for storage through charging so that it can be use later on when needed.

A solar powered inverter works best in locations where there is an abundant supply of sunlight and that's why it would do well in many tropical African countries like Nigeria where the sun is available for most parts of the year. Considering the rising costs of electrical energy and the fact that supply is barely meeting demand, the Nigerian government is encouraging Solar power investors to set up businesses in Nigeria that would help provide electricity to many remote areas of Nigeria since they have good sunlight.

More and more businesses and families are gradually switching over to solar energy as a means of generating their electricity needs. I read a story about a barbing salon guy in northern Nigeria who generated enough electricity to power his electric clipper and fan for the day and that saved him money considering the fact that he had been spending more to buy petrol to power his generator in an isolated village in Nigeria. For them, a solar powered inverter system has helped to provide what the power companies had not been able to provide for a long time. Solar powered systems make people less dependent on power companies and end up having to pay little or no bills to them. The only cost of using an off-grid solar powered inverter system is the equipment and setup cost. Once installed, such power systems can last for up to 10 years or more.

How much power a solar panel can generate depends on the Power capacity of the solar panel as they come with different specifications such as 100 watts, 200 watts and so on. How much electrical power your inverter system can store wouldl also depend on the capacity of the deep cycle batteries connected to your inverter. The more batteries or battery capacity that you have, the more space it would have to store more power which you can use for the longer term. So, a single deep cycle battery may not store as much power as 2 or 4 batteries would be able to. Also, the amount of power you electronic devices normally consume would also depend on how long the inverter can keep supplying power. So, if you were using just a light bulb, your power can last for up to 10 hrs while if you include an electric fan and a TV with decoder, it may last less than that because of usage. The bottom line is that the more money you invest in a solar powered inverter system in terms of batteries and solar panels, the longer it would be able to keep supplying electricity to you. If you are on a tight budget, you can just go with 1 battery and a single solar panel which should be able to power your lights and tv for up to 4 hrs a day.

A 100 watt solar panel is built to supply 100 watts every hour and for 4 hrs, it should ideally be able to supply 400 Watts. However, we need to deduct energy losses during electricity generation using 0.85 as a factor and that means it would be able to supply about 340 watts for the 4 hrs giving 340 Watts-Hours.

We also need to know the type of battery that we need to work with the 100 watts solar panel that can generate 340 WH. Let's assume that it's a 12 Volt battery, then we can calculate the Amp Hours(AH) using the forumula: WH/V and hence; 340/12 gives 28 AH indicating the type of battery that we need that would be able to store the energy generated by the 100 watt Solar panel. You can probably use a battery with a higher capacity or use a lower power solar panel e.g. 50 watts.

In your Solar power connected inverter, you will also need a charge controller connected in between the solar panel cable and the batteries so that they don't get over-charged or discharged. The charge controller is normally one that corresponds with your battery charging capacity in Amps such as 10A, 20A and so on. Without a solar charge controller, your battery could get damaged and it's better to protect it.

One of the things you'll need to decide on first before setting up a solar power system of this kind is how much power you really need. You can decide to power your entire home or you can choose to only power a few devices. An easy way to find out how much power your electronic devices use is by looking at their manuals or specs printed at their backs. At the back of your TV, you may see something like 200 Watts and that means it uses that much power in 1 hr. It's about the same thing for all your other devices such as your electric fan and light bulbs. Just check their power usage and add the Watts up so that you know how much power you really need to generate and store for later use with your inverter.

A Solar powered inverter system is something everyone can install at his home or office independently without having to wait for the power company. It's normally ideal in isolated places but also recommended for people who don't want to keep paying bills to the power company and keep the world greener.