Ice accretion is one of the potential dangers of the aircraft. Surface dielectric barrier discharge (SDBD) based plasma anti-icing is one of the novel methods that has the advantage of energy efficient, fast response and geometrical simplicity. A "stream-wise plasma heat knife" configuration was proposed based on nanosecond pulsed SDBD for better anti-icing performance. A set of wind tunnel experiments were conducted to study the performance of the "stream-wise plasma heat knife" quantitatively. Spatial-temporal distribution and the dynamic process of icing on a NACA0012 airfoil model were obtained. An analysis of the balance between discharge energy and anti-icing energy was introduced, an energy efficiency eta(total) approximate to 15.6-21.6% was found to be appropriate as the ratio between heating energy and total deposited energy during discharge. A good agreement between analytical results and existing experiments was achieved, providing a good prediction of the anti-icing performance for nSDBD based plasma anti-icing devices. (C) 2019 Elsevier Ltd. All rights reserved.