Grid Connection System

What is Grid Connected System

How do we feed solar generated energy back to the grid?

When Solar PV system comes into mind, most people would think of battery storage, using energy generated to be self sufficient and be independent of the grid. While this is true for a standalone system (or Off-Grid System), we will try to illustrate a different and somewhat new concept of Grid Connected System which is also known as On-Grid System.

On-Grid vs Off Grid

Standalone PV System (Off Grid)

  • 1. Employed in remote locations without access to utility grids
  • 2. Completely relieves you from dependency on electrical grids
  • 3. Typically require larger up-front investment cost due to additional components
  • 4. Generally larger system compared to grid connected system
  • 5. Has more number of solar modules and battery for storage

How Off Grid PV System Works?

The basic concept for standalone system is that; since electricity generated by sunlight is not constant (intermittent), batteries have to store electricity produced by solar PV to provide constant flow of electricity when needed!

Grid Connected PV System (On Grid)

  • 1. Generate electricity, sending this energy back to TNB power grid.
  • 2. TNB will be paying you to produce energy for them, since the energy you produce offsets the energy your home or business uses.
  • 3. TNB meter will credit your account for the electricity you sell to them and offset your monthly utility bill under “net metering concept.”
  • 4. Electricity produced is not stored
  • 5. System is disconnected from grid during power failure for safety reasons

How Grid Connected PV System Works?

  • 1. The basic concept for grid connected system is that; since electricity generated by sunlight is not constant (intermittent), whatever electricity produced is fed to the grid and production recorded by outgoing meter.
  • 2. Electricity is drawn from grid when needed.
  • 3. Effectively same as a function of a battery at lower cost and same environmental benefit!

A typical residential layout of components for Grid Connected System