Control Systems

The point thresholds for the different levels of LEED certification, based on LEED-NC 2009, are outlined in Table 1.3

The most recent revision of LEED-NC emphasizes energy efficiency and indoor environment quality. This is reflected in

the significant increase in potential points

in the Energy & Atmosphere credit category from 17 in v. 2.2 to 35 in v. 3.2,4

Other LEED systems have similarly high point allotments in the energy and

atmosphere section.

This column outlines where and how

the use of control systems has been integrated

into qualifying for LEED points

for certification. LEED-NC (New Construction and Major Renovations) is used as the reference rating system.

The need for using control systems

is evident by their being mentioned specifically throughout the Energy and Atmosphere, Indoor Environment, and even Site Sustainability credit categories. Points can be attained by reducing light pollution, optimizing and monitoring the

building’s energy performance, controlling

lighting, and providing a comfortable and safe indoor environment. Table 2 summarizes some of the credits

that can be gained with the help of control systems.3 Table 2 totals a possible 29 points obtainable through strategies in which controls

play an integral part. For example, the LEED-NC 2009 guidance suggests input

power reductions for interior lighting after hours with limited override determined by occupancy sensors, and suggests CO2 and

airflow sensors to trigger the HVAC system directly or to trigger the building automation

system to alter the ventilation/outdoor air delivery as needed by the interior. To accomplish the Measurement & Verification credit, energy consumption

trend monitoring systems and control

system diagnostic alerts are suggested. For the Lighting Controllability of Systems

credits, occupant based control and

task based controls are suggested.3 One

company claims that the use of their lighting

energy management system with occupancy and photo sensors and a variety

of control strategies (time scheduling, occupancy control, task tuning, etc) can

help to gain any of the 29 points listed.5

Overall, LEED 2009 encourages automated

and manual controls as a means to

reduce building energy consumption and to improve the building’s indoor environment and outdoor environmental impact.3 It takes 40 points for a building to become LEED certified. Thus, it is feasible to obtain a large fraction of the points needed for LEED certification

by choosing to meet credits that suggest or require an energy control system.

With current technologies and software, lighting and HVAC systems can be automatically controlled, scheduled, and monitored based on occupancy, space use, and time of

...