The ongoing projects of heavy ion accelerators, like LHC at CERN and at GSI in Darmstadt, will require high-intensity ion beams, ≈ 1 emA, of heavy elements like Pb27+. Electron cyclotron resonance ion sources (ECRIS) are good candidates for delivering such beams. Now they reach the domain of multi-Tesla magnetic fields and they can be realized almost only by superconducting windings. Correspondingly, the rf generators that can supply these ECRIS are gyrotrons in the 28–37 GHz frequency range, powerful enough to ionize and to heat up the large ECRIS plasmas. The first ECRIS operation at 28 GHz using a gyrotron, which is reported in this paper, was carried out on the superconducting device SERSE. Other ECRIS projects of this new generation are now under-way; they are shortly presented with their expected performances, together with some ECRIS prospects.