Commitment to Energy Efficiency, Reducing Carbon Footprint, and Preserving the Natural World
Design backed up by an explanation of each design process shall be documented with thorough explanations and plaques to educate anyone who visits the house. For example:
To construct a building responsibly requires early planning and a well thought out, integrated design process where all who contribute to the design are involved from the beginning of the project. Each element of construction must reflect a commitment to energy efficiency, reducing the carbon footprint and preserving the natural world. As a result the building will cost much less to operate and maintain than a conventional building. The design and construction process shall be well documented and the finished product shall highlight innovative features to demonstrate all existing renovations to the surrounding community, greater Philadelphia and beyond. Maintaining the principles that have resulted in financial and honorable awards over the past five years is crucial to the future success of the project. Student developed concepts and standards have made the house attractive and successful up to this point. The design shall allow Smart House to serve its purpose, which is to live and experiment with sustainable cutting edge technologies and to serve as a demonstration model for the community.
Bringing Daylight Indoors
A partnership with Summalux LLC, a Baiada Center Incubator Company and Drexel Smart House Spin-off
The built environment presents significant challenges to designers seeking to maximize daylight integration. Further, indoor spaces incorporating significant amounts of daylight have been shown to enhance occupant productivity and health, most notably by regulating the circadian rhythm, preventing seasonal affective disorder (SAD), and other conditions such as shift work dysfunction. Daylight simulation, made possible by energy efficient LED technology, has the potential to reproduce the benefits of natural sunlight. These lighting products are especially suited for commercial spaces with limited sunlight exposure, as well as residential and retail environments.
Recent advances in LED packaging, power conversion drivers, and thermal management technology are making LED lighting products more affordable for general use. Drexel Smart House and Summalux LLC plan to outfit the entirety of the 3425 property with daylight simulation lighting fixtures and study the impact on occupant health and productivity.
Cool Roof Coatings
Sponsored by the U.S. Environmental Protection Agency
Also supported by the Dow Chemical Company, Advanced Materials Division and Potter's Industries
This project's goal is to develop a low cost cool roof coating formulation which improves upon the infrared reflective properties of commercially available white coatings. This is accomplished by incorporating novel materials with unique optical properties and specially engineered pigments and additives into a water based acrylic binder. This project is part of the Smart House's Heat Island Mitigation research initiative.
Solar Gain is in part responsible for up to 56% of energy consumed by cooling systems in residential buildings1. Additionally, high building density in the urban environment contributes to the urban heat island effect. According to the EPA2, regions exhibiting the urban heat island effect can be as much as 10ºF warmer than their rural counterparts, and these regions may see as high as a 22ºF difference in temperature between day and night. Mitigating the urban heat island effect has the potential to reduce cooling demand, peak demand, and heat related illnesses and fatalities.
By applying cool roof coatings to a building's exterior, cooling loads can be reduced and urban heat islands can in part be mitigated.3 Many commercially available cool roof coatings are white paint formulations based on titanium dioxide.4 Although titanium dioxide and other pigments are effective at scattering visible wavelengths, they exhibit strong absorption in the infrared region.5 By incorporating controlled voids in a coating as the scattering medium, the void size distribution can be optimized for broadband radiation scattering.6 The purpose of this project is to design a coating utilizing glass hollow microspheres as a means of controlling void diameter to achieve a low solar gain roof.
Glass Hollow Microspheres are the primary filler in our coatings. Our current formulation has been specially designed to promote polymer binder - sphere adhesion while preventing sphere breakage, visible in two of the above images. Images © 2009 Drexel University, Department of Materials Science and Engineering.
1. Department of Energy. 2007 Buildings Energy Data Book, U.S. Department of Energy. http://buildingsdatabook.eren.doe.gov/
2. Environmental Protection Agency. "Reducing Urban Heat Islands: Compendium of Strategies" Retrieved March 12, 2009. http://www.epa.gov/heatisland/resources/ pdf/BasicsCompendium.pdf
3. Environmental Protection Agency. "Reducing Urban Heat Islands: Compendium of Strategies - Cool Roofs" http://www.epa.gov/heatisland/resources/pdf/ CoolRoofsCompendium.pdf
4. J. Beltley and G. P. A. Turner, Introduction to Paint Chemistry and Principles of Paint Technology, 4th ed. (Chapman and Hall, London, 1998), p. 105-106, 110.
5. Cole, Joseph R; Halas, N.J. Optimized Plasmonic Nanoparticle Distributions for Solar Spectrum Harvesting. Appl. Phys. Lett. 89, 153120 (2006).
6. Dombrovsky, Leonid A; Randrianalisoa, Jaona H; Baillis, Dominique. Infrared radiative properties of polymer coatings containing hollow microspheres. Intl. J. of Heat and Mass Trans. 50 (2007) 1516–1527
This research has been supported by a grant from the U.S. Environmental Protection Agency's Science to Achieve Results (STAR) program.
Residential Green Roof System
One of our latest projects, the residential green roof group seeks to develop a green roofing structure and system suitable for integration in residential properties. One of the challenges faced by the team early on was the structural evaluation of the 3425 property. Since an evaluation was recently carried out on the property, design requirements have been set and the team is planning to design a green roofing platform suitable for installation on the original roof structure of a 19th century Victorian twin home.
The most significant challenge the team is faced with is identifying a light weight replacement for the growing medium (most commonly soil or clay) that can be sourced within 500 miles of the installation site. Sourcing perlite, a lightweight volcanic soil, on the east or west coasts is feasible since it is mined on both coasts. Shipping perlite over 500 miles to the midwest incurrs a carbon footprint, since fuel is used for the transport of perlite. LEED outlines how building materials should be sourced, and specifies a 500 mile radius for it's local materials point.
This growing medium must balance high water retention with good drainage properties while supporting plant life. Smart House researchers use several test methods to measure water retention and drainage, as well as freeze stability, density, erosion, and pH.
Further impacts of this research include the potential for sloped green roofing systems and vertical outdoor walls.
Green roofs have the potential to reduce a building's environmental impact by offering water retention, thereby reducing water runoff to surrounding areas. Additionally, the roof vegetation serves to reduce cooling loads by reducing heat gain. Significant implementation of green roofs and cool roofs can in part mitigate the urban heat island effect.
Web Based Energy Monitoring Sensor Network
The Drexel Smart House provides an innovative model for future urban homes in order to demonstrate how the quality of life can be improved through smart design and technology; reducing environmental impacts, providing a healthier environment, simplifying daily tasks. The house is a permanent testing ground for innovative technologies, prepares technology for wide-scale adoption, helps shape new markets, and pushes the envelope in governmental and regulatory restrictions to allow for easier sustainable design. We aim to make technology accessible to individuals regardless of age or technical experience. We monitor and maintain a healthy home with healthy and happy residents. We commit to increase the efficiency and productivity of the residents while reducing their impact on the environment. The overall effect is a demonstration of the symbiotic relationship between technology and sustainability in the modern home.
The building is just the beginning. The real value of the Drexel Smart House program is in the research and design projects conducted by student members. Drexel Smart House will create an unprecedented opportunity for a large group of dedicated students from diverse fields within the university to work toward a common goal:
Community Resource Center
Community Resource Center as envisioned in a student generated rendering.
A Community Resource Center open to the public will be a place where homeowners in Powelton Village can get questions answered from knowledgeable students and/or faculty. Information about systems used in the Smart House or general conclusions gathered over time from the research at the Smart House will be available for homeowners to learn what can work best in their own homes to improve the overall quality of living. A library will house references such as guides for techniques on how to achieve energy efficient and environmentally responsible designs and catalogs from local vendors within a 500-mile radius.
Rainwater Harvesting System
Rainwater Harvesting System as envisioned in a student generated rendering.
Collects rainwater to prevent storm water from entering Philadelphia’s Combined Sewage Overflow (CSO) system, which is a major issue the city is set out to resolve. The stored water is used for irrigation and to flush toilets and is made available for students to test various filtering systems and explore future possibilities for re-using rainwater and greywater. Capturing rainwater for irrigation and flushing toilets conserves water and saves money spent on the water supply.
Drainage from the roof will water planters in the lobby through pipes from the roof before it enters the cistern, as seen in the student generated rendering of the public entrance off of 35th street: To the right pipes coming from the roof direct rainwater to planters filled with a specific plant species that improve the indoor air quality. When it rains the plants automatically get watered, and the plants naturally filter the water as it permeates through the soil into a trough where the water is then directed to the rainwater storage tank in the basement.
The Living Water Tower
Rain travels through roof drains and trickles down a series of exposed sculptural “steps” which are visible at the entrance of the building and double as an aesthetic water feature. The rainwater then reaches and fills the same cistern used for the planters in the lobby. The water from the cistern is constantly re-circulated using a solar powered pump back to the top of the roof and then back down through the “Living Water Tower” through drip irrigation lines. This system never allows the water to sit still for too long which could result in bad bacteria formation. Cold water from the underground storage tanks is filtered and pumped up into the building for use in clothes washing, hand washing and showers. Other water from the storage tanks is pumped to the roof where it is circulated through solar hot water heaters and back down to provide hot water for showers, sinks and washing machines. Waste water from hand washing, clothes washing and showers is taken through a series of filtration basins in the tower filled with gravel, sand and soil with micro-organisms that feed off the waste and purify the water. At the end of this extensive filtration process, water is pumped back into the system. In this way, water is never wasted, but can be reused indefinitely.