What makes a passive house a passive home?

On Saturday, Duke Smart Home students hosted Iowa State professor Mikesch Muecke to share his knowledge of sustainable building techniques. Muecke’s presentation focused on passive housing. A passive house can maintain a comfortable indoor climate without relying upon active heating and cooling systems. Specialized designs make this possible, utilizing the natural light and heat of the sun, as well as super-efficient insulation to reduce heating or cooling loss. The Smart Home utilizes some of these techniques in its own design. [ More about passive houses ]

In this way, “architects are responsible for a big chunk of energy use,” Muecke said.



The basic features of a passive home include:

• compact form and good insulation


• southern orientation and shade considerations


• energy-efficient window glazing and frames


• air-tightness of the building


• highly efficient heat recovery from exhaust air


• hot water supply using regenerative energy sources


• energy-saving household appliances

Passive homes require substantially less energy than their actively heated and cooled counterparts. If a passive home is fitted with solar panels, sometimes it even produces surplus energy that can be fed back into the energy grid. In other words, instead of a homeowner paying the electricity company, it pays them. Not a bad deal.

Muecke also discussed the Solar Decathlon, an international competition hosted by the U.S. Department of Energy in which students compete to design and build the best energy-efficient, solar powered house. The finished homes are shipped to Washington D.C. and displayed on the National Mall. For a week, the houses are open to the public, and are evaluated by experts in terms of their architecture, market viability, engineering, lightning design, comfort zone, and other criteria.

In 2007, the last year the competition was held, Germany’s Technische Universitat Darmstadt took first place. But come this October, Muecke and his team from Iowa State University have their eye on it. [ Check out Iowa State’s passive home concept ]

Smart Home, Smart Lighting

Smart Home, a live-in laboratory at Duke University, is a place where inter-disciplinary research meets practical needs.

After having won one of the most prestigious ratings in green buildings, called the Platinum LEED rating (given by the US Green Building Council), Smart Home has established itself as a foremost example of focusing holistic research on sustainable building techniques. Students from many majors continuously work in groups on projects for the Smart Home and compete for the Will Senner Grants Award Competition and the Cisco Innovation Award.

One of the interesting projects that won the Will Senner Grants Award Competition late last year was an all-freshman team whose research focuses on tapping the vast potential of the sophisticated lighting system of the Smart Home.

The ambitious goal is to work on the lines of sustainability and greatly reduce the wastage of light and energy in homes. Some of the immediate subprojects include a night light system- a system in which if a resident arrives late at night, the path to his room can be lit so as to avoid disturbing other residents with excessive light; measuring the REM sleep cycle of the person so that the lights and other electronic equipment can instantly switch off once the person is asleep, thereby saving huge amounts of energy; a light notification system that is directly connected to the door bell, so that instead of creating noise by ringing the bell, the residents can be notified of visitors through a subtler system of flashing of lights; night time protection that will systematically and logically turn lights on and off to mimic the presence of someone in home all the time, even during vacation, hence provides protection.

The research narrows down to the fact that through the power of fuzzy logic, the programmable lights in Smart Home can be made to fulfill several functions that can enhance day-to-day lights as well as provide a further step in promoting sustainability.