(1) No person shall be excused from testifying or from producing evidence in any proceeding held by the Public Utility Commission on the ground that the testimony or evidence required of the person may tend to incriminate the person or subject the person to prosecution, penalty or forfeiture if:
(a) The person has been directed by the commission to testify or produce evidence under oath;
(b) The person claims, at the time the person is directed by the commission to testify or produce evidence, that the testimony or evidence required of the person may tend to incriminate the person or subject the person to prosecution, penalty or forfeiture; and
(c) The commission specifically grants the person immunity from prosecution, penalty or forfeiture regarding those matters about which the person testifies or produces evidence as directed.
(2) Except for prosecution and punishment for perjury, no person who testifies or produces evidence in accordance with subsection (1) of this section shall be prosecuted or subjected to any penalty or forfeiture concerning any matter about which the person so testified or produced evidence.