Here are a few common questions with Absorb Solar’s answers to help you, however, if you have a solar related question not listed below that you need an answer to, please ask using the contact form on our site.
What size system should I go for 12v, 24v or 48v?
The higher the current (measured in Amps) the bigger the components need to be. High currents require large diameter cables and fuses, both of which are expensive. By doubling the voltage you get double the power (Watt) at the same current. However if you were using 2v cells to create your system voltage your number of batteries double as you change from 12 to 24 and then to 48 which will also have an increase on system cost.
Standard Charge controller or MPPT?
Standard PMW charge controllers are a usually a low cost charge controller which is matched in voltage to your battery bank they vary in Amp input depending on your solar array. MPPT controllers are far more sophisticated, you can add multiple strings of panels increasing the voltage therefore decreasing the Amps and cable size. MPPT also maximize the solar power by adjusting the input voltage depending on condition of sun and load.
How long will solar panels last?
Most manufactures guarantee a lifespan of 20 to 25 years with performance dropping off after 20 years.
Do lead acid batteries require a lot of maintenance?
The specific gravity of each battery should be tested monthly this is an easy task which involves checking the quality of the battery acid using a hydrometer.
A visual check should also be done monthly to check the water level in each battery, if low distilled water should be added.
What are the main components of a stand alone system?
- Solar panels
- Charge controller
- Inverter / Charger
- Battery bank