Tips to buy inverter and battery for home to survive power cuts
Thinking of buying inverter and battery for home? How do you decide which inverter to buy or what specification of battery to go for?
You can take advice from your friends and family to decide which brand to buy, but it’s not just inverter and battery brand that you must think of. They can suggest you most popular brands to buy which are advertised on TV like Exide inverter battery, Luminous, Microtek, Sukam, etc. But, just because they are advertised on TV, does not mean they are the best brands to go for or the best models to cater to your requirement.
Also, how would you know what power and capacity to look for? Other parameters that can help you make an informed decision include the power requirement, maintenance, etc.
Role of inverter and battery
Appliances in our home need electricity to run, which comes in the form of AC (Alternate Current). At the time of power failure, the supply of AC is cut and hence you need alternate source of power generation to run your appliances.
One option is to buy a battery to generate power at home for few hours.
But batteries generate electricity in the form of DC (Direct Current), whereas our appliances run on AC. So, that’s where you need an inverter. An inverter sits between the battery and the appliances and converts DC output of battery into AC input for your appliances.
INVERTER BATTERY TYPES
First of all, batteries used for inverters are different from automotive battery. You cannot use your car or truck battery to run the inverter.
All inverter batteries in Indian market are rechargeable lead acid batteries. Some require more maintenance, and some are ‘almost’ maintenance free. Broadly speaking, there are two ways to categorize lead acid inverter batteries.
When differentiating batteries based on electrolyte technology, the two battery types are:
Flooded lead acid batteries or Wet Cell batteries
Sealed Lead Acid (SLA) or Gel Cell batteries
Flooded or wet cell batteries are the standard lead acid batteries which requires more maintenance and needs to be kept upright all the time.
SLA batteries are also known as maintenance free batteries, although it still requires some sort of cleaning and is more expensive than flooded ones. SLA battery are also known as VRLA (Valve regulated lead acid) battery
When differentiating batteries based on plate technology, the two battery types are:
Tubular inverter batteries
Tubular inverter batteries are more sophisticated with life span that could be 8- 10 years and are more efficient than flat plate lead acid batteries.
T-plate battery is a type of flat plate battery and uses advanced technology. T-plate inverter battery has been patented by Exide.
Note: You’ll find wet cell battery with flat and tubular plate and similarly you’ll get gel cell battery with flat and tubular plates.
There are two types of inverters in the market- sine wave inverter and square wave inverters. When nothing is mentioned, by default, it is a square wave inverter. read more about sine wave inverter and its comparison with square wave.
POWER REQUIREMENT OF INVERTER AND BATTERY
You don’t want to end up buying an inverter that can power 8 CFLs and 8 fans when your requirement is to create power backup for only 2 CFLs and 2 fans. Why? With increased power of inverter, battery capacity will also increase. And that will cost you more! Ideally, whatever electricity requirement is to be met by the inverter, go for the one with around 20% more capacity.
Now that you understand the function of inverter and battery for home use, it’ll be simpler make an informed decision while buying.
1. Identify the appliances you want to connect to the inverter to be able to use them in case of power failure. Let’s say you decide to connect 1 fan and 2 CFL.
1 + 1
2. Calculate the power consumption of these appliances.
1 —> approx 70 Watts
1 —-> approx 50 Watts
Power requirement= (1 X 70) + (1 X 50) = 120 watts
So, your total power requirement is 120 watts
3. To be able to buy inverter, find the power of inverter measured in VA, for which the formula is:
Power of Inverter (VA) = Power requirement (watts)/ Power Factor (efficiency)
= 120 watts/.7 [Assumed efficiency of 70%]
300 VA inverters are available in the market which is closest to 171.43VA. So an inverter with 300 VA will be a good choice for your home if you want to connect 1 fan and 1 CFL for three hours.
4. Find out how many hours of backup can be provided.
- Assumed value of battery voltage —> 12 V
- Battery Ampere = 171.43 VA / 12 V = 14.3 A
- Battery Size —> 100 Ah
- Assuming 90% efficiency of battery, available battery capacity —>90Ah
Battery Capacity Ah = Battery Ampere X hours
90 Ah = 14.3 A X hours
hours= 6.25 hours
Another thing you must check is the warranty period of inverter and battery. For inverters, usually 2-3 year warranty is offered.
You must consider the space required to install inverter and battery. For example, if you buy lead acid inverter battery, then you must place it in well ventilated area. Also from maintenance point of view, the area should be approachable.
Many people get inverters installed in store room or kitchens. That must be avoided.
There are many well known inverter brands in the market like Exide inverters, Luminous inverters, Microtek inverter, Sukam and Genus inverter.
Good Inverter battery brands include Exide inverter battery, Luminous, Amaron.
Electromatic Sales is a multi-brand dealer of inverter and inverter batteries in Kanpur.