The Commission may authorize a financial contribution only for participants who meet all of the following criteria:

(a) The participant represents particular interest, expertise or point of view that can reasonably be expected to contribute substantially to a full and fair determination of the issues involved in the proceeding;

(b) The economic interest of the participant in any Commission determination related to the proceeding is small in comparison to the participant's costs of effective participation in the proceeding. If the participant consists of more than one individual or group, the economic interest of each of the individuals or groups comprising the participant shall also be considered, if practicable and appropriate; and

(c) The participant does not have sufficient financial resources available for effective participation in the proceeding, in the absence of a financial contribution.