PV Solar Electricity Generation Systems

Basics of each type of system of PV System

GRID-TIED SYSTEM

  • Electricity from this PV installation is consumed directly at home or business.
  • No batteries = No electricity from the PV installation when very cloudy or at night.
  • Low maintenance, depending on the dust in the area cleaning of the panels may be needed.
  • Approximately 20 year life span, but you may have to replace the inverter after 10 years.
  • Some municipalities allow you to feed electricity back into the grid and will compensate you for this. If you live in an area where this is not allowed, or should you choose a tariff structure with no grid feed back allowed, the generated electricity that is not immediately used, will be lost.

A grid-tied system requires an active grid connection to operate, thus the PV system will not produce electricity during load shedding.

 
OFF-GRID SYSTEM

  • The system consists of PV panels, invertor and battery pack.
  • The sizing of batteries depends on your required load (kWh used) and solar resource in the area (the number of days without sun you need to energize: the more cloudy days, the bigger the battery).
  • Batteries require regular maintenance. The batteries will need to be checked weekly by the owner. It is best to have your system serviced yearly.
  • Approximately 20 year life span, but you may have to replace the in-verter after 10 years. Batteries will last from 2 to 10 years, depending on the usage profile and maintenance record.

For off-grid systems use gas or solar thermal energy for heating applications to reduce the required battery capacity, for example use a solar water heater for water heating and cook with gas.

 
HYBRID SYSTEM

  • The hybrid system consists of PV panels, invertor, grid connection and battery pack.
  • Backup power is limited to the capacity of the battery bank.
  • Batteries require regular maintenance. The batteries will need to be checked weekly by the homeowner. It is best to have your system serviced yearly.
  • Approximately 20 year life span, but you may have to replace the in-vertor after 10 years. Batteries will last from 2 to 10 years, depending on the usage profile and maintenance record.

If you have a hybrid system installed, the batteries should only power essential loads, for example lights, computers and freezer/refrigerator.