1. CLEAN THE SOLAR PANEL REGULARLY
Most permanent solar panels sit sitting nearly flat on the roof, which means dirt and dust that has been collecting on the surface of the solar panel has nowhere to go. Cleaning the solar panel periodically will ensure the solar cells are achieving maximum exposure to the sun, thus maximising their overall efficiency.
2. MINIMISE VOLTAGE DROP BY INSTALLING YOUR REGULATOR CLOSE TO THE BATTERY
Voltage drop can wreak havoc on a solar system, especially if it confuses the solar charger/regulator. For example, if there is 0.5V voltage drop between the solar regulator and the battery, a 14.4V charging voltage from the regulator will be received as just 13.9V at the battery.
The problem is, the regulator does not pick up on this voltage drop and will still think the battery is fully charged when, in fact, it’s not. In short, voltage drop will mess up the communication between the regulator and the battery, and best way to eliminate this problem is to simply install the regulator as close to the battery as possible, and use electrical cable thick enough for the job.
3. HAVE A BATTERY BANK THAT IS A BIT LARGER THAN NEEDED
Having two batteries as opposed to one can actually increase the lifespan of both batteries in the long run. The reason being, most AGM batteries have a rated cycle life of about 500 at 50 per cent depth of discharge (DOD) and more than 1200 at 25 per cent DOD.
This means in standard testing conditions, the battery will last for 500 cycles if it’s discharged to 50 per cent for every cycle and it will last for more than 1200 cycles if it’s only discharged for 25 per cent every cycle instead. This means, theoretically, when we double the size of our battery bank (two batteries), we will reduce our DOD from 50 per cent to 25 per cent and the lifespan of our batteries will extend more than twice! So what do we get? Well, basically you get a battery system that cost less money in the long run, and is larger in overall capacity.
Rule of thumb: If your battery bank goes down to 12V quite often, it’s worth increasing the capacity of your whole battery bank.
COMMON QUESTIONS – SIMPLE ANSWERS
Why is it the more I clean the panels the dirtier they get?
If you tend to use a polishing motion to clean your solar panel, there’s a good chance you’re actually creating a static charge, which attracts dust particles. The best way to keep your solar panel clean is to wipe it over with a water/detergent mix, before rinsing it with clean water (with a small amount of detergent) and letting it dry on its own. The detergent actually acts as an anti-static agent.
Is it normal for my solar charger to reduce in the afternoon?
Yes. This is mainly because as the battery increases in charge the solar regulator consequently reduces its output accordingly. Plus the sunlight is usually fading, which does help much!
My solar charge is higher than the maximum output of the solar modules, is this normal?
In some locations, it is possible for solar panels to receive reflective sunlight in addition to the direct sunlight. This is usually around water or sand where light reflects upwards towards the underside of a cloud and back down. It’s usually a short-lived occurrence due to the angles of sunlight that need to line up perfectly to make it happen, but it can boost solar input by up to 30 per cent which is nothing to sneeze at.
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