279 Paragraph replacedwith The Energy Services Interface (ESI) is the external face of the energy consuming node. The ESI may be directly on an energy management system in the end node, or it may be mediated by other business systems. The ESI is the point of communication whereby the entities (e.g. utilities, ISOs) that produce and distribute electricity interact with the entities (e.g. facilities and aggregators) that manage the consumption of electricity. An ESI may be in front of one system or several, one building or several, or even in front of a microgrid.