It’s no secret that Nigeria is practically in darkness. The power sector is still trying to get its act together after its privatization. This has led many citizens to seek alternative forms of power. In the not too distant past, generators (diesel & fuel) were the popular choice, however, recent technology advances have birthed other forms of alternative energy. Solar PV, wind, biogas, inverters, etc. have all been introduced and used in Nigeria. Of these mentioned, standalone inverters are probably the cheapest.
Read: Best Power Alternatives
It is important to understand what the right inverter for your home is. The power requirement at your home can be different from that of your friend or neighbour. Do not blindly install the same inverter. Before picking an inverter, you must do some homework and understand the basics.
Here are some things to know before picking an inverter:
You Must Know Your Power Requirement
One important factor to note before buying an inverter is your power requirement. Your power requirement is the total load of all the electrical appliances you want to run with the inverter. You have to consider how many appliances you intend to run and the voltage of each one. For example, if you want to run 3 CFL light bulbs, 2 fans, 1 laptop, 1 television and 1 refrigerator, you’ll have to consider the load for each one.
3 CFL light bulbs- 25W x 3= 75W
2 Fans- 70W x 2= 140W
1 Laptop- 50W
1 Television- 120W
1 refrigerator- 150W
Total power requirement- 535W
Find the VA rating of the Inverter
VA stands for Volt Ampere rating. It is the voltage and current supplied by the inverter to the appliances. If an inverter operates with 100% efficiency, then the power requirement of the electrical appliances and power supplied by the inverter is the same. However, 100% efficiency does not exist. Most inverters have an efficiency range of 60-80%. This efficiency is also called the power factor of an inverter and is simply the ratio of power required by the appliances to power supplied by an inverter.
With the above example, let’s consider the power factor to be 0.7. The VA of the inverter then becomes 765VA (535 / 0.7). The right inverter to pick with this power rating is an 800VA inverter.
Know the battery your inverter needs
The battery is the backbone of a standalone inverter system. The life and performance of an inverter largely depend on the battery quality. The next big question is “how much back up will an inverter provide?” or for “how many hours it can run all of your appliances?” This is what is called the battery capacity. It is the battery capacity that decides the backup hours. It is expressed in Ah (Ampere Hours).
Batteries with a capacity of 100 Ah, 150 Ah, 180 Ah etc. are readily available. To find out which works for you, you must calculate the battery capacity.
Battery capacity = (Power requirement (in watts) * Back up/running hours) / Battery Voltage (in volts).
Using the above example:
Battery Capacity = (535 * 6) / 24 = 133.75 Ah
** Value of Battery voltage is taken 24V
Therefore a battery with a capacity of 130 Ah will work for you.
By understanding this simple calculation you not only save yourself from the misleading information shared by inverter dealers but also help yourself in taking the correct decision.
Pay Attention to the Type of Inverter
Inverter types depend on the kind of AC wave they produce. The common types are the pure sine wave and the modified sine wave.
The pure sine wave inverter produces the type of power you get from the grid or a generator. The advantage of this type of inverter is that all electrical appliances are designed for a sine wave. This guarantees that appliances will work to its full specifications. Some appliances like motors and microwave ovens will work to full efficiency only on sine wave power. Sine wave inverters are more expensive.
The modified sine wave inverter produces a waveform similar to a square wave but with an extra step. A modified sine wave inverter will work fine with most appliances but their efficiency will be reduced. Some appliances like refrigerators, fans, etc. will use more power due to reduced efficiency. Most appliances will use 20% more power and may make a buzzing sound. They are however cheaper than the pure sine wave.