Plug Load Control

What are Plug Loads?

Plug loads include devices connected to standard receptacles, such as task lighting, monitors, chargers, and other electronic equipment. Even when not actively in use, many of these devices continue to consume electricity through standby, or "vampire," loads. Plug load controls automatically shut off designated receptacles when spaces are unoccupied, helping reduce energy waste, lower operating costs, and improve building efficiency without impacting occupant comfort or behavior.

Terms to Know - Plug Load Control Fundamentals

Term	Definition	Why It Matters
Plug Load	Electricity used by devices plugged into receptacles, such as monitors, printers, chargers, coffee makers, and other equipment left in standby mode.	Plug loads can account for a significant portion of a building's energy consumption.
Plug Load Control	A system that automatically turns receptacles on or off to reduce wasted energy.	Helps customers save energy and meet energy code requirements.
Energy Waste	Electricity consumed when equipment is operating unnecessarily.	Identifying waste creates opportunities for cost savings.
Standby Power (aka Vampire Load, Phantom Load)	The electricity used by devices when they are plugged in but not actively being used.	These hidden energy costs add up over time, especially across large buildings with hundreds of devices.
Energy Efficiency	Using less energy to perform the same task.	A key goal for most building owners and facility managers.
Uncontrolled Receptacle	An outlet that always remains energized.	Critical devices should remain plugged into uncontrolled receptacles.
Controlled Receptacle	An outlet that can be automatically turned on or off by a control device.	The core component of most plug load control solutions.
Split Receptacle	A receptacle where one outlet is controlled and the other remains always on.	Provides flexibility for users.
Occupancy-Based Plug Load Control	Automatically energizes and de-energizes controlled receptacles based on occupancy.	Prevents devices from turning on when no one is present. One of the most common plug load control triggers.
Schedule-Based Plug Load Control	Turns controlled receptacles on and off according to programmed schedules.	Reduces after-hours energy consumption. Ideal for predictable operating hours.
Automatic Shutoff	Power is removed from a device after a programmed condition is met.	Eliminates unnecessary energy waste.

Codes and Standards

Energy codes and standards require Receptacle Control or Plug Load Control. IECC, ASHRAE 90.1 and California Title 24, Part 6 require controlled receptacles to have the same automatic shutoff function as lighting using either occupancy sensing or schedule-based control. Plug-in strips and devices cannot be used for code compliance. Title 24 and NEC also require the controlled receptacles to be permanently marked to differentiate them from uncontrolled receptacles.

Big Three Code Compliance

Requirement	ASHRAE 90.1 2025	2024 IECC	2025 California Title 24
Where Automatic Receptacle Control (aka Plug Load Control) is Required	Offices, conference rooms, break rooms, classrooms, workstations, modular furniture	General building area requiring controlled receptacles	Office areas, lobbies, conference rooms, kitchens, copy rooms, hotel/motel rooms
Number of Receptacles That Must Be Controlled	50% of receptacles in covered spaces 25% of modular furniture circuits	Controlled receptacle required at each location (split or adjacent)	Controlled receptacle required near each uncontrolled >50% in hotel/motel guestrooms
Placement Requirement	Percentage-based (no distance requirement)	Within 12 inches of each uncontrolled receptacle or split receptacle	Within 6 ft of each uncontrolled receptacle
Allowed Control Methods	Time-of-day schedule, occupancy sensors, or automated system signal	Time-of-day schedule, occupancy sensors or automated system signal	Time-of-day schedule, occupancy sensors, or automated system signal Guest rooms include key cards
Auto-OFF Timing	Within 20 minutes of vacancy	Within 20 minutes of vacancy	Within 30 minutes (guest rooms) General spaces require automatic shutoff
Scheduled-based Control	Yes, with <2-hour override	Yes, programmable daily; <2-hour override	Yes, with <2-hour override

Controlled Receptacles

Split Controlled

One outlet (top or bottom) is controlled, other is always ON
Offers flexibility for users who need both controlled and always-ON power
Common in offices and hotel rooms

Full Controlled

Every outlet in the receptacle is controlled
Maximizes energy savings but may require more planning for critical devices

Design Tip

Use split receptacles where users need access to both types. Use full controlled where plug loads are non-essential or predictable.