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Tools for High-Performance Analysis

With Algor 3D modeling software, Steven Winter Associates measure heat flow through building components. These visualizations show how heat follows the path of least resistance, through conductive materials like aluminum window frames or concrete structural slabs. Analyses like this should inform more effective detailing of buildings.

Daylighting can greatly reduce electric lighting needs. The section diagram shows how step dimming allows us to turn off lights when enough daylight penetrates into a space. Deeper into the building, the amount of light needed from electric lighting increases.

An investment in automatic dimming has been calculated to return a five- to seven-year payback. However this was based on energy prices before the California crisis began. Now that energy rates are higher, computed payback periods for efficiency measures such as this will greatly decrease.

With software such as Lightscape and Radiance, 3D computer models can be rendered with accurately simulated daylight and electric lighting. Light levels are quantified and graphically represented so that one can quickly assess deficiencies as well as areas in which lighting levels could be reduced.

When pursuing natural ventilation schemes, architects must understand airflow and temperature gradients. Steven Winter Associates use computational fluid dynamics modeling to simulate the process of air entering the building through openings and moving through the designed space.

This tool can also be used to study HVAC functionality. With multiple section cuts color-coded by air temperature, it is possible to see if the air is mixing properly and if it is at the right temperature at the right place where it is needed for heating or cooling. These studies allow for system optimization, replacing traditional system oversizing.

This conference session reinforced the concept that good ideas need good design and data in order to be implemented. This level of study has not traditionally been part of the building design process but is essential to achieve integrated building solutions that perform at high levels of efficiency.

Ross A. Leventhal is a designer at NBBJ in Seattle, Washington. Refer to Best Practices in Sustainability for more of his observations about this conference.

Progressive dimming provides adequate light levels with less electricity. Image: Steven Winter Associates A Lightscape-rendered space displayed qualitatively, yet accurately. Image: Steven Winter Associates Precisely calculated, color-coded luminance levels in a Lightscape rendering. Image: Steven Winter Associates A Radiance rendering indicates glare at the windows without a lightshelf. Image: Steven Winter Associates When a lightshelf is added, Radiance demonstrates reduced glare and light bounced deeper into the space. Image: Steven Winter Associates   Click on thumbnail images to view full-size pictures.