Off-Grid Solar System
This solar system is a battery based solar system which does not need a grid. It is a complete solar setup with solar panels, solar battery, and solar inverter, and it comes with a power backup.
HOW DOES AN OFF-GRID SYSTEM WORKS?
An off-grid solar system uses a solar panel to absorb sunlight and convert it into electricity. In the day time solar will run the connected load and balance energy will be stored in the solar battery. In the daytime, the solar system runs appliances generating electricity using sunlight and stores the extra energy into the battery bank. And at night when there is no sunlight, the appliances draw energy from the battery to keep running. Hence, the system works day and night
Components of Off-Grid Solar System
Following are the components of an ON-GRID solar system:-
SNo. | Description of Component | Warranty |
1 | Solar Panels – Monocrystalline OR Polycrystalline | Manufacturing Warranty: 10 yrs Performance Warranty: 25 yrs |
2 | Off-Grid Inverter | Warranty 10 yrs |
3 | Solar Battery (Lead Acid or Lithium Ion) | Lead Acid Battery 3-5 yrs Lithium Ion Battery – 10 yrs |
4 | Standards Mounting Structure | Standard 12 Months |
5 | ACDB & DCDB | Standard 12 Months |
6 | DC & AC Cables, Earthing Cables | Standard 12 Months |
7 | MC 4 Connecters | Standard 12 Months |
8 | Earthing Electrodes & Lightening Arresters | Standard 12 Months |
9 | Other Accessories such as cable tie, crimping tools | Standard 12 Months |
All components are MNRE approved.
ADVANTAGES & DISADVANTAGES OF ON-GRID SOLAR SYSTEM ADVANTAGES:-
- System provides you a battery backup as per requirement.
- Dependency on Grid connectivity not required.
- Works without electricity, hence do not have to deal with electricity bill.
- ROI in 5 to 7 years.
- It can install anywhere.
DIS-ADVANTAGES:-
- More expensive & less efficient than ON-GRID Solar
- Wastage of Power if not in use & batteries are fully charged.
- Lead acid batteries need to replace after warranty period.
- Lead acid batteries need to add water frequently.
- Does not saves electricity bills to extent 90% as compared to On-Grid System
- Cannot add more loads due to system Load limitations.
INVERTER BATTERY BACKUP TIME FORMULA:
FORMULA:
Backup Time (in hours) = Battery Capacity (in Ah) x Input Voltage (V) x Efficiency %(n) / Total Load (In Watts)
To understand this formula, let’s assume you have an inverter battery with 150AH capacity, 12 V of input voltage, and 80% discharge Efficiency. You have 2 tube lights of 40 watts, 2 fans of 75 watts, and 1 Wi-Fi router of 20 watts working on this battery.
How long will it last in this case? Let’s calculate:
Let’s first figure out what the total load per hour is:
2 Tube lights = 40 x 2 = 80 Watts
2 Fans = 75 x 2 = 150 Watts
1 Wi-Fi Router = 1 x 20 = 20 Watts
The total load, in this case, is 80+150+20 = 250 Watts. Now, let’s put these values in our formula:
Backup Time (in hours) = 150 x 12 x 0.8 / 250 = 5.76 Hours
So, your 150 AH inverter battery is expected to provide 5.76 hours in this case.
Does the smaller or larger capacity of the battery make a difference?
Obviously, it would make a huge difference. Here are calculations of a smaller and a larger capacity of batteries:
If the capacity would be 100Ah:
Backup Time (in hours) = 100 x 12 x 0.8 / 250 = 3.84 hours
So, with a 100 AH battery, we would’ve got a backup of just 3.84 hours. If the capacity would be 220Ah:
Backup Time (in hours) = 220 x 12 x 0.8/ 250 = 8.448
With a 220 AH battery, We would’ve got a backup of 8.448 hours, which is much more.
So, you can see that battery capacity, whether 100, 120, 135, 150, 200, 220, or 240 Ah, plays a massive role in how much backup you’ll have.
The more capacity, the more backup time you’ll get.
But that doesn’t mean you need to purchase a higher AH battery.
Observe your battery backup time needs and choose accordingly. One should have a min 3 hours of backup time in India.
Inverter Battery backup time calculation table:
CAPACITY VS LOAD | 100 WATT | 200 WATT | 300 WATT | 400 WATT | 500 WATT | 600 WATT | 700 WATT |
80 AH | 7.68 Hrs | 4.08 Hrs | 2.72 Hrs | 2.04 Hrs | 1.64 Hrs | 1.36 Hrs | 1.16 Hrs |
100 AH | 9.60 Hrs | 4.80 Hrs | 3.20 Hrs | 2.40 Hrs | 1.92 Hrs | 1.60 Hrs | 1.37 Hrs |
120 AH | 11.52 Hrs | 5.76 Hrs | 3.84 Hrs | 2.88 Hrs | 2.30 Hrs | 1.92 Hrs | 1.65 Hrs |
135 AH | 12.96 Hrs | 6.48 Hrs | 4.32 Hrs | 3.24 Hrs | 2.60 Hrs | 2.16 Hrs | 1.85 Hrs |
150 AH | 14.40 Hrs | 7.20 Hrs | 4.80 Hrs | 3.60 Hrs | 2.88 Hrs | 2.40 Hrs | 2.05 Hrs |
180 AH | 17.28 Hrs | 8.64 Hrs | 5.76 Hrs | 4.32 Hrs | 3.46 Hrs | 2.88 Hrs | 2.46 Hrs |
200 AH | 19.20 Hrs | 9.60 Hrs | 6.40 Hrs | 4.80 Hrs | 3.84 Hrs | 3.20 Hrs | 2.74 Hrs |
220 AH | 21.20 Hrs | 10.56 Hrs | 7.04 Hrs | 5.28 Hrs | 4.23 Hrs | 3.52 Hrs | 3.01 Hrs |
240 AH | 23.40 Hrs | 11.52 Hrs | 7.68 Hrs | 5.76 Hrs | 4.60 Hrs | 3.84 Hrs | 3.30 Hrs |
Remember, you need a capacity that will give you at least 3 hours of backup time at a given appliance’s watt load.
Honest Advice:
An off-grid solar system is ideal for those who want to get rid of frequent electricity cuts. This solar system is the ultimate solution for those who are suffering from a shortage of electricity and who do not have a reliable grid (government electricity supply). It is a self-sustainable system that ensures power supply throughout the day and at night as well.
As the name indicates, this system switches off the grid (main power grid) as a result of which you stop getting monthly electricity bills. This system allows you to live in any part of the country no matter how far it is from the power grid.