Solar Power Backup Systems
Solar power backup systems provide
a safe and reliable alternative when a blackout occurs. Depending on your
needs, an appropriately size reserve system can meet your electrical load
and up-time requirement. If you have critical energy needs for computers,
communication equipment or electric heaters, such a system may be
right for you.
Backup power is usually provided by gas or diesel generators to
create electricity. However, they cannot provide immediate power
since they need to be primed and started before delivering power.
In addition, regular maintenance is also required to ensure the
motors are in good working order and the fuel is not contaminated
A backup solar power system, on the other hand, works quietly
and efficiently in the background during the day, ensuring the battery
banks are continuously charged. A non-interruptible power supply can
be created for critical applications, like computer and communication
systems, so important data or functions will not be suspended when the
main power goes out. The following 5 components make up a complete system:
1. Solar Panels
The number of solar panels depends on the load and the up-time duration.
First, determine how much energy your electrical equipment requires. All
equipment will state the amount of power in Watts that are needed for
peak operation. Once you know the total power requirement, use this number
to determine how many of solar panels needed for your application.
many solar panels does it take to make one kilowatt?]
2. Charge Controller
A charge controller is necessary to maximize the amount of current
generated from the solar panels. Ensure that the controller has an
auto-disconnect feature that will disengage the batteries from the
solar panels once they're fully charged. This will prevent damage
to the batteries that can be caused by overcharging and will also
prevent any charge leakage from the batteries when the solar panels
3. Battery Bank
The number of batteries you'll use again depends on the load and up-time
requirements. Once you determine your energy requirements and estimate
how long a blackout may last in your area, you can then determine how
many batteries you need. For example, if your equipment requires 300 W
of power, then the battery requirement will be as follows:
One 20 AH battery operating at 12 V will be able to supply 240 WH:
20 AH x 12 V = 240 WH
Five 20 AH batteries operating at 12 V will be able to supply 1200 WH:
(5 * 20 AH) x 12 V = 1200 WH
A battery bank with 5 batteries will be able to supply:
1200 W for 1 hour or
600 W for 2 hours or
400 W for 3 hours.
Batteries should be checked regularly for fluid levels and leaks.
They can be placed outdoors but should be kept out of the cold and
have proper ventilation (small amounts of hydrogen gas will be
expelled during the recharging phase).
An inverter is necessary for converting DC power from the batteries
into AC power for your equipment. There is a small energy loss in
the circuitry but is usually about 95% efficient.
Using the above calculation, five 20 AH batteries will supply 1200 WH
of power. If the inverter is 95% efficient, then the usage will be as
1200 WH x 95% efficiency = 1140 WH
1140 WH for 1 hour or
570 WH for 2 hours or
380 WH for 3 hours.
5. Transfer Switch
A transfer switch is a circuit that can quickly switch the input
power from the grid to the battery backup. The operation should
be instantaneous to provide an uninterruptable power supply to
your load. Look for a unit that mechanically separates the two
supplies with a relay so current will not leak from the batteries
out to the grid and vice-versa.
Solar power backup is a reliable system for critical equipment.
It is more costly than having the batteries recharge directly from
the grid but will continuously top up the reserve whenever the sun