That's a good question, as there are significant differences between Tier 1 and Tier 2 APS in terms of both features and functionality. This article outlines and attempts to explain these differences.


Tier 1 APS

A Tier 1 APS works on a simple master/switched principle using current sensing technology. When the control device (a TV or PC) is on, the switched outlets (and hence the peripherals) are powered on. When the control device (a TV or PC) is switched off, the switched outlets and peripherals are powered off. Energy savings are derived from ensuring that peripherals are switched off when the TV is not in use. Higher energy savings occur when users leave peripheral devices in the on state – something that is common with AV receivers and DVD players. A Tier 1 APS relies on user behavior to switch the TV on and off for generating energy savings. Tier 1 APS are simple to install, compatible with >99% of TVs, reliable, cost-effective, and form an important part of many energy savings programs in North America.


Tier 2 APS

A Tier 2 APS is an enhancement to a Tier 1 APS. In addition to master/switched functionality, the APS also controls the TV based on user engagement, or more specifically, the lack thereof. The principle is to generate extra energy savings from the TV when a user is no longer present by switching the TV off along with the peripherals (e.g. children have wandered off or someone has fallen asleep in front of the TV).
Motion Sensing

A Tier 2 APS functions in a very similar way to an occupancy sensor for a light. If no one is in a room for a period of time, then the light is switched off.

To determine user presence an additional sensor, external to the APS is included. This sensor senses for user engagement and is typically either:

  • •   An infrared (IR) remote control sensor, or
  • •   A multi-sensor (infrared and motion sensing)

The sensor works in conjunction with a countdown timer that resets each time user engagement is sensed. When no user engagement (absence) is sensed for a period of time, the countdown timer expires, and the TV is switched off automatically, thereby generating energy savings from both the TV and peripherals.

The Tier 2 APS energy saving principle is engagement AND behavior based rather than relying simply on user behavior as with a Tier 1 APS.



As a rough rule of thumb, a Tier 2 APS is roughly three times the cost of a Tier 1 APS due mainly to the additional sensor and more complex electronics. In addition, a Tier 2 APS is slightly more complex to install and so is best suited to Direct Install (DI) programs, which increases the overall measure cost vs. a Tier 1 APS (which can be self installed via a less costly retail or kit program delivery method).

TIER 1 OR tier 2 aps?


This depends on a few different factors;

  1. 1. What type of program delivery and installation options are available?
  2. 2. What is the budget?
  3. 3. Is the primary objective to maximize energy savings?

The answer is often a combination of these factors. Tier 1 APS is a simple, cost-effective measure that can be easily installed and used in kit programs, residential direct install (AV and home office) and commercial workspace applications. With the ability to cross so may program delivery types, Tier 1 APS make great sense for efficiency programs.

Where an efficiency program is looking to maximize residential (AV) energy savings, the budget permits and the APS can be direct installed; a Tier 2 APS is a great option.

Regardless of the program objective, TrickleStar has an APS solution to meet every requirement.