As used in this article, the term:

(1) "Adequate market conditions" means the existence of market conditions in relation to distribution service within a particular delivery group that have been determined pursuant to subsection (b) of Code Section 46-4-156 to warrant customer assignment.

(2) "Affiliate" means another person which controls, is controlled by, or is under common control with such person.

(3) "Ancillary service" means a service that is ancillary to the receipt or delivery of natural gas, including without limitation storage, balancing, peaking, and customer services.

(4) "Commodity sales service" means the sale of natural gas exclusive of any distribution or ancillary service.

(5) "Control" includes without limitation the possession, directly or indirectly and whether acting alone or in conjunction with others, of the authority to direct or cause the direction of the management or policies of a person. A voting interest of 10 percent or more creates a rebuttable presumption of control. A voting interest of 25 percent or more is deemed to constitute control. The term control includes the terms controlling, controlled by, and under control with.

(6) "Customer assignment" means the process described in subsection (e) of Code Section 46-4-156 whereby retail customers within a particular distribution group who are not under contract for distribution service from a marketer are randomly assigned to certificated marketers.

(7) "Customer service" means a function related to serving a retail customer including without limitation billing, meter reading, turn-on service, and turn-off service.

(8) "Delivery group" means a set of individual delivery points on one or more interstate pipeline suppliers to a gas company that may be aggregated and utilized for the distribution of gas to a particular set of retail customers.

(9) "Distribution service" means the delivery of natural gas by and through the intrastate instrumentalities and facilities of a gas company or of a marketer certificated pursuant to Code Section 46-4-153, regardless of the party having title to the natural gas.

(10) "Electing distribution company" means a gas company which elects to become subject to the provisions of this article and satisfies the requirements of Code Section 46-4-154.

(11) "Firm" means a type of distribution service which ordinarily is not subject to interruption or curtailment.

(12) "Interruptible" means a type of distribution service which is subject to interruption or curtailment.

(13) "Marketer" means any person certificated by the commission to provide commodity sales service or distribution service pursuant to Code Section 46-4-153 or ancillary services incident thereto.

(14) "Person" means any corporation, whether public or private; company; individual; firm; partnership; or association.

(15) "Retail customer" or "retail purchaser" means a person who purchases commodity sales service or distribution service and such purchase is not for the purpose of resale.

(16) "Straight fixed variable" means a rate form in which the fixed costs of providing distribution service are recovered through one or more fixed components and the variable costs are recovered through one or more variable components.

(17) "Winter heating season" means the calendar days from October 1 of one year through March 31, inclusive, of the following year.