The boom of fluctuating renewable energies puts forward higher requirements on reserve capacity for maintaining the power system balance. To address this issue, this letter investigates a novel distributed event-triggered consensus control (ETCC) method of large-scale inverter air conditioners (IACs) for demand response, which can achieve the same regulation objective and response speed while significantly relieving the communication burden compared with traditional time-scheduled consensus control methods. Based on Lyapunov stability theorem, we also prove the convergence of the ETCC with nonlinear protocol for massive IACs. Finally, the above models and methods are verified by numerical studies.