Stand-alone solar backup system

What is a stand-alone solar backup system?


Stand-alone solar backup systems are completely independent from the power grid. They are perfect in areas where it is too expensive or remote to connect to the power grid. They have the added bonus of giving you backup power during load shedding. They work as follows:


Solar panels produce electricity that power appliances while excess energy is stored in battery banks. In the event that solar panels cannot supply sufficient electricity, backup power is drawn from the batteries.


In situations where it is important that power is available around the clock, other sources of power such as wind turbines or diesel generators may be connected to the system.


The components of a solar backup system


Power generated by the solar panels flows to the batteries as direct current (DC) and needs to be converted to alternating current (AC) before it powers the appliances.


Consequently the stand alone system requires different components for this to happen. These components are:


Photovoltaic Solar Panels


Solar panels need to produce more power than a battery uses to charge.


As an example, a 12V battery will use 14.4V to charge.


Therefore, in order to charge a 12V battery, a solar panel with a Voc of about 20V is needed.


Charge Controllers


Their two main functions are:


To prevent batteries from overcharging by stopping power flow from the solar panels once they have sufficient charge. Power then goes directly to the inverter and appliances.


To provide batteries with protection from negative flow. When a small amount or no power is produced at all and power flows from the batteries to the solar panels.




Batteries that can handle near constant charging and discharging are known as deep cycle batteries. Good deep cycle batteries require high charging efficiency low charging currents and low self-discharge.




Inverters turn DC power that comes from the batteries into AC current, which is what most of the appliances in the house run on.


What are the advantages of having a standalone system?


  • They protect you against electricity rate hikes
  • Your lights stay on during load shedding
  • It adds value to your property
  • It reduces harmful greenhouse gas emissions
  • Minimal maintenance costs
  • In remote areas it is cheaper than connecting to the electricity grid


If you require more information on the system or would like to arrange for installation of a Battery Backup System, simply complete our contact form.