Behind the meter (with demand user) refers to energy storage facilities that are connected to commercial and industrial users’ sites. They provide customers electricity bill savings and grid services (such as power supply if grid supply fails). Examples of this would be to cover the lag between the user requiring power when the grid isn’t supplying enough – frequency response, TRIAD (storing cheap rate electricity for use rather than buying peak rate from the grid) or uninterrupted power supply (USP)
see also “In front of the meter”