A PV system can be ground mounted or freestanding, fitted on a residential or commercially owned roof, or even used as an alternative to traditional building materials (for e.g. roof tiles, paving on roads, etc.).
There has been an increasing customer interest for rooftop PV installations in Pakistan, even though there is an absence of policies and standards for the promotion of PV technology. Electricity generated from a rooftop installation can be used to supplement the building’s own electrical requirements as well as be directed back into the grid as and where permitted by AEDB and NEPRA.
Classification off Rooftop PV Systems
The most common way to differentiate a solar rooftop installation is via the connection to the electrical load/grid.
- Grid Tied System with Reverse Power Blocking: The property is connected to the national grid in order to receive electricity, but any surplus electricity generated by the system is prevented from being directed back into the grid.
- Grid Tied Connected (Net Metered): Electricity generated can be used at the property and any surplus can be directed back into the grid. In some cases, this feed-back is compensated for.
- Off-Grid / Standalone: The PV system generates electricity for use on-site, and operates completely independent of the national grid. In this case, it necessary to have additional components such as a charge controller and battery storage.