Curtailment (export limiting)
The deliberate reduction of an inverter's output below what the array could deliver, in order to respect an export limit set by the network operator. Zero export means the system is curtailed whenever generation exceeds on-site demand.
Curtailment is implemented with a meter at the connection point feeding a signal back to the inverter, which then modulates its output within a required response time. It is increasingly common where distribution networks are constrained, and zero-export conditions are a normal outcome of connection applications in some regions. Design consequences follow directly: with export capped, a larger array only pays if the surplus can be self-consumed or stored, and the case for battery storage strengthens. Do not confuse curtailment with clipping — one is a regulatory instruction, the other an inverter capacity limit.