MIT team finds that the ratio of component atoms is vital to performance.
An MIT web site will soon enable architects to see quickly and easily whether they can save energy and increase comfort by facing their new building south rather than west.
Such decisions are usually set in stone well before assessments of energy consumption and comfort levels are undertaken. The new web site will perform those assessments based on general information, so architects can try out basic options such as building orientation, room size and window technology before proceeding with a more detailed building design.
Helping architects, developers and city planners reduce energy consumption and improve indoor air quality is critical, said Leon R. Glicksman, the George Macomber Professor of Construction Management and director of MIT's interdisciplinary Building Technology Program. Buildings now consume more than a third of the energy and half of the electricity used in the United States. And the incidence of "sick buildings" (those with unhealthy air quality) is on the rise.
Developing advanced technologies that can help is one goal of the Building Technology Program, which involves collaborators from the Departments of Architecture, Civil and Environmental Engineering, and Mechanical Engineering, and the Laboratory for Energy and the Environment. But an equally important mission is to provide tools that will encourage the more widespread use of simple, easy-to-implement methods that already exist.
"I believe we can find ways to build buildings that consume substantially less energy than today's do while providing improved air quality and good comfort--all at little or no increase in cost," said Glicksman.
Many of the advanced technologies being studied at MIT show considerable promise. Among them are novel low-energy ventilation approaches that ensure clean air near occupants, advanced window systems that control solar energy and insulation levels, new designs and materials for high-performance thermal insulation, and advanced metering and diagnostic systems for controlling building and appliance operation.
But developing better technologies won't help unless architects use them--and there's evidence that American architects don't use them as much as they could. For example, many European buildings are now designed to maximize natural ventilation. When the outdoor air is comfortable, winds carry it inside naturally, supplying both fresh air and cooling without energy-consuming mechanical chillers. MIT assessments show that natural ventilation could be effective in many types of buildings and many geographical areas in the United States.
So why aren't such "sustainable" practices being used? According to Glicksman, one problem is that architects don't have adequate simulation tools to guide them. Sophisticated computer programs can predict the energy performance of a building, but figuring out how to use the programs can be a time-consuming challenge. In addition, they require detailed information from architectural drawings. By the time blueprints are available, many critical decisions affecting a building's energy use have already been made. At that point, asking broad questions such as "what happens if the building turns 90 degrees?" isn't practical.
Glicksman and a team of building-technology students have been working to bridge that gap. Their goal is to develop a publicly available web site with intuitive graphical tools that architects, developers, city planners and others can use to explore their options in the initial phases of design. To achieve their goal, the researchers have created algorithms that can perform rapid, real-time calculations of sustainability indices. And they have developed an interface that permits users to make design choices with a click of a button and see results in colorful graphs and images.
EASE OF USE
Suppose you want to put up a commercial building in Boston. The web program asks you to specify the building's orientation and to define a sample room, including its dimensions and the window size and type. (Windows are key to the analysis because they're the primary source of heat loss and solar gain.) Charts spring up that show energy consumption for heating and cooling, comfort levels at specific locations within the room, and even exactly how daylight will enter the room during selected seasons, times of day, and with and without blinds (tilted at an angle of your choice). A few clicks show the effects of reorienting the building or buying fancier, high-tech windows.
The MIT researchers have tried out their site on several types of potential users. Last May, they exhibited it at a conference of professionals from the building and control systems industries. They also sent it to researchers at Tsinghua University in China, who have collaborated with building-technology faculty on large-scale building designs demonstrating the advantages of sustainable practices. And an architectural student from the project's sponsoring company, Permasteelisa S.P.A. in San Vendemiano, Italy, came to check out the look and feel of the site.
The web site is the product of work by a number of past and present MIT students. The original inspiration and the science behind the energy model came from Daniel Arons (S.M. 2000). Continuing the work are graduate student Matthew Lehar of mechanical engineering on the programming side and James Gouldstone (S.B. 1995 and S.B. 1996) on the web presentation side. Melissa Read, a sophomore in mechanical engineering, is preparing important documentation for the site, including user-friendly "help" instructions.
A beta version of the new site can be accessed using Internet Explorer only at http://www.buildingenvelopes.org and clicking on "tools" (free registration required). The final site should be ready for all users in late spring; look for it on the Building Technology Program's home page .
A version of this article appeared in MIT Tech Talk on February 6, 2002.