A comprehensive source for understanding the lighting models underlying the commercial lighting power limits developed in ASHRAE/IESNA 90.1-2004.

Energy standards behind Lighting Power Density.
Glossary of LPD Terms.

Public Discussion about Lighting Power Densities.

Fill out our survey.

Contact LPD Committee Members.

Illumenating Engineering Society of North America
American Society of Heating, Refrigerating, and Air-Conditioning Engineers, Inc.

LPD Members

Explore lighting power density models for entire buildings.
Whole Building LPD

Explore lighting power density models for individual spaces.
Space Type LPD

Experiment with your own power density models.
Calculator

View/Download the
User Guide
in Adobe Acrobat pdf format.
Get Acrobat Reader

The IESNA Energy Management Committee (EMC), working with the Lighting Subcommittee of the ASHRAE/IESNA 90.1-2004 Standing Standards Project Committee (SSPC) has developed an interactive methodology for determining lighting power densities for both individual spaces and whole buildings. This methodology is the basis for the lighting power density numbers found in the ASHRAE/IESNA 90.1-2004 Standard.

This methodology calculates lighting power allowances for building spaces and whole buildings. The process models lighting design assumptions from a consensus of lighting design professionals for each of the space types used in 90.1-2004, using currently available efficient lamp/ballast/fixture data, and illuminance values from current IESNA illuminance recommendations. In this way, the needs of the occupants are taken into account and energy-efficient design is promoted through the resulting lighting power densities.



Direct questions or concerns about this website to ies@ies.org
2005 IESNA. All rights reserved.