The “service” that natural gas and electric end users receive actually comprises two services: commodity (the supply of natural gas or electricity) as well as delivery of the commodity from the source of production and/or an interconnection with a transmission system. Unbundled service happens when the distribution company provides the delivery service but another entity such as a marketer or aggregator provides the commodity service. While the delivery of the commodity on the distribution system remains a monopoly service, in many regions some or all customers have a choice of commodity supplier.
Below is an example of unbundled service:
The opposite of unbundled service is bundled service in which the distribution company provides both distribution and commodity.