A Grid Export Control is a type of device/technology which is used to limit/control the amount of power produced by a power plant that is injected into the grid. In India, it is used to control or limit fully against injection where either the customer opts for it or the DISCOM/Grid-Operator doesn't support/accept the injection. In this case, it becomes a Zero Grid Export Control or simply a Zero Export Device/Control.
In many cases, it is used due to Time-of-Day (TOD) practices, where during certain time window(s) of the day the DISCOM, could be operating under different load conditions, tariff rates, performing maintenance, etc, that could affect the grid-stability and health.
Let us consider a Solar Photo-Voltaic Power Plant, where a Zero Grid Export Control/Device limits the active power injection into the grid. This setup might be needed to alleviate the grid network from power overloading and decrease the cost of grid-infrastructure upgrade which this could imply otherwise.
Zero grid export is being eliminated across many states in India as well as around the world and now zero export becomes the priority of the day. Modern Solar Inverters have the Export-Control functionality built-in to their system and might need only measuring devices (such as CTs to monitor and interact). Urja GreEnergy with its Power Control Device has the ability to dynamically control the energy output from older Solar Inverters & thus achieve Zero-Grid-Export of electrical energy to the DISCOM grid.
During Zero-Grid Export, the power generated from the Solar PV Power Plant will be used only for self-consumption or limits any grid injection. However. In some nations, the grid operator does not allow energy injection into the grid. This is known as zero grid export or injection limitation.
Zero grid exports ensure that the inverter is instantly ramped down at an appropriate speed which ensures there isn’t a reverse feed to the grid, and solar power is generated at the optimal/required speed according to the load requirements.
However, there is one highlighted use-case scenario where there is a need to control the export of energy to avoid catastrophic collateral damage to the power backup setup. It is the Generator Set that cannot handle reverse feed-in of power that needs to be controlled/stopped to avoid burn-out of the alternator as well as the engine connected to it.
