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Electron Cyclotron Resonance Heating (ECRH) is the main heating system for the W7‐X stellarator and the only one for CW‐operation in the first stage. The mission of W7‐X, which is presently under construction at IPP‐Greifswald, is to demonstrate the inherent steady state capability of stellarators at reactor relevant plasma parameters. W7‐X is therefore equipped with a superconducting coil system operating at 3 T and a divertor for 10 MW steady state heat removal. A 10 MW ECRH plant with CW‐capability at 140 GHz is under construction to meet the scientific objectives. The commissioning of the ECRH plant is well under way, the status of the project and first full power, cw test results are reported.

A multi parameter statistical analysis of Lower Hybrid Current Drive (LHCD) efficiency has been carried out on all the data available for the Frascati Tokamak Upgrade (FTU). The volume of the parameters space scanned is quite large and of direct interest for ITER. The positive dependence of the CD efficiency with 〈Te〉 has been confirmed. Comparing the results with the expectations for the CD process, a reasonable agreement is found for the ion charge, Zeff, dependence (CD efficiency ∝1/(Zeff+5)), while the influence of other parameters (like qa, ne, BT, N∥) is discussed in detail. Clear evidence of the synergy between the lower hybrid and electron cyclotron (EC) waves is found, provided the EC power is directly absorbed on the fast e− tails. The effect of different N∥ (LH parallel refraction index) spectra is also investigated.

The ECRH experiment (up to 2 MW for 0.5 s) planned on the FTU tokamak (major radius R=0.93 m; minor radius a=0.3 m; toroidal magnetic field Bt up to 8 T) has now reached its realization phase. A preliminary system with only a fraction of the full power (0.5 MW for 15 ms) has already been installed and tested. The simulations here presented refer to these data. Moreover predictive computations for the global experiment are discussed.