PV Hybrid solutions are a combination of multiple energy sources to fulfill two main objectives - back-up power and energy saving. These solutions can either supplement power usage directly and use a generator or battery storage as back-up power.



A system that utilizes a PV grid-tie system with a back-up inverter is called an AC-coupled PV Hybrid solution. An alternative solution is the DC-coupled PV Hybrid solution where the MPPT solar charge controllers are coupled to the battery to utilize energy, or offer around the clock energy saving when the sun goes down. 



  • Generator

  • Generator & back-up inverter/online UPS

  • Back-up inverter/online UPS


PV Grid-Tie with backup inverter large enough to carry PV Grid-Tie with or without online UPS.


PV Hybrid solution with solar chargers coupled to DC bus.


PV Hybrid solution


  • Double-Conversion Online UPS’ isolate the supply from the load, the result is no transfer time at all, and the load has a constant voltage source with no fluctuations.

  • No maintenance

  • No noise


  • No maintenance

  • No noise

  • No delay in transfer time


  • Lower cost




The recommended inverter topology is a low frequency transformer-based inverter. The loads connected to systems like these are generally highly inductive and capacitive loads as well as the longevity of the inverter running such loads depend on the topology.

Especially if the system is to be AC coupled with PV, only LFTB inverters are Bi-directional and can handle the back feed of excess energy from PV Grid-tie inverters for battery charging.

The storage technology would depend on the frequency of the battery cycling, the temperature the batteries will be exposed to and whether or not the solution will be expanded to a solar PV solution in the future that might utilize battery storage for additional energy saving.

For solutions where the batteries will only be used for standby and the frequency of the battery utilization is less than once per week, the ambient temperature of the batteries are fairly constant and not exceeding 35°C; lead-acid batteries will suffice. Applications with the inverse of any of the above factors should utilize lithium batteries.


Online UPS’ are made for sensitive loads and the inverter topology is less robust – in most cases high frequency switching transformer-less technology is used. This makes it a more feasible solution.

Most online UPS’s have unconventional voltage range which make them incompatible with conventional PV technology like MPPT solar chargers, for this reason, they won’t be cycled frequently also very often these batteries are installed in server rooms which have temperature control implemented, for both of the above mentioned, in most cases UPS’s make use of lead-acid battery technology.


Small (<12kVA) portable generators should include functionality as: 

  • Pull or electric start. 

  • With or without an automatic voltage regulator (AVR) if used with an inverter or UPS then it should include this.

  • Generally, petrol engines. 

  • Generally, they aren't silent types. 

Large (>12kVA) stationary generators can include functionality as:

  • Manual or automatic start based on mains failure

  • Should have a decent automatic voltage regulator (AVR) – especially if it is to be used with inverter or UPS technologies.

  • Fuel type can be Gas (LPG or Natural) or Diesel engines

  • Automatic Transfer Switch (ATS) 

  • Protection devices that take care of overheating, oil pressure, output quality monitoring with automatic shutdown and more. 

  • Generally, they are silent types.


  • For AC coupled solutions The Grid-tie inverters used for PV Hybrid solutions run in parallel with the load and do not physically support the capacity thereof, for this reason High frequency transformer-less topology is suitable and mostly used. 

  • For DC coupled solutions the MPPT solar chargers should be matched with the brand of inverter for best functionality, monitoring and reliability. 

  • The elaboration on various PV panels technologies and which is best is quite elongated. However, the conclusion we have derived is. 

    • If you have a space restraint mono-crystalline 

    • If space is no concern poly/multi crystalline



The criteria here would be dependent on feasibility and reliability. The solution is a combination of back-up power and PV power.


The back-up portion's storage may be sized only to:

  • Carry critical loads for the duration of power outages

  • Keep the entire load connected for a set duration

  • or to mostly or completely alleviate the utility supply usage


 The most independent solution may not always be the most viable one, the load profile, maximum demand, consumption and tariff structure play a key role in determining the most viable solution. The solutions are also scalable; however, it is best to establish what the result should be and then break up the solution into acceptable portions. 


We design, supply and install these based on the customer’s needs.

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