A bipolar electrosurgical system is provided. The system includes at least one pair of active and return electrodes each including thermally-conductive tubular members with closed distal ends. Each of the tubular members include electrically conductive portions which are adapted to connect to an electrical energy source. The active and return electrodes are further configured to penetrate tissue and create at least one generally elliptical lesion therebetween upon activation of electrical energy. The system also includes a multiplexer disposed between the electrical energy source and each pair of electrically conductive active and return portions. The multiplexer is adapted to selectively switch electrical potentials of each pair of active and return electrically conductive portions to create lesions of varying geometry.