U.S. Department of Energy's Solar Decathlon | Powered by the Sun

Solar Decathlon 2013

Norwich University

Team website: www.nusd2013.org

Norwich University's mission at the U.S. Department of Energy Solar Decathlon 2013 was to show that high-performance, solar-powered dwellings can be affordable and beautiful. The Delta T-90 House accommodates New England's unique seasons and is designed to be affordable for those earning 20% less than the Vermont median income.

Design Philosophy

The house explores the hidden values and richness within a conservation-based lifestyle and respects the interdependency between the economy and the built environment. The Delta T-90 House is guided by the beliefs that high-performance, solar-powered dwellings should be available to all and that good design is not a function of cost. By maximizing the building envelope first and then using simplified mechanical systems as a supplement, the design prioritizes passive functionality and reduces primary energy demand to minimize lifetime operational costs.


  • The locally harvested northern white cedar rain screen draws from the traditional wood siding found in barns and utility buildings across New England.
  • A flat roof with a fully integrated photovoltaic array introduces modern elegance and accommodates the region's average of 120 days of annual snow.
  • Thick, 16-inch walls with deep-set windows minimize heat loss and reinforce a spirit of protection and strength.
  • Ample daylighting and high ceilings, rarely found in affordable housing options, create a grand and spacious ambiance.
  • No floor area is dedicated to mechanical systems, making every square foot of floor area (excluding storage and laundry areas) usable by occupants.


  • The building-integrated photovoltaic system, with panels that adhere to the flat roof, eliminates the weight and costs associated with racking and mounting hardware. These panels work in low levels of sunlight to provide power to the house even in less-than-optimal solar conditions.
  • A mini-split heat pump HVAC system with a single supply diffuser provides widely available, compact, and easily serviceable heating and cooling without the need for duct work or overt mechanical elements.
  • The heat-recovery ventilation system provides continuous ventilation to the interior while reducing humidity levels and keeping the building envelope dry. The system is 92% efficient, ductless, and whisper-quiet.

Market Strategy

The Delta T-90 House is attuned not only to the climactic demands of the Northeast but also to the financial demands of the population that lives there. The house is a cost-effective alternative to housing built before 1950, which often had inefficient systems and inadequate insulation. It is designed for a family of three that makes near or below the median income and is intended to be produced in high quantities. It maximizes comfort, efficiency, and spaciousness through two bedrooms, an office space, and an open living space for lounging, cooking, and gathering—offering a model for affordable and sustainable living.

What's Next

Following Solar Decathlon 2013, the Delta T-90 House will venture to Frank Lloyd Wright's Westcott House in Springfield, Ohio, to take new life as an experiential design lab. Integrated into the Westcott House Foundation's regular tour program, the house will also serve as a catalyst for design education activities to foster dialogue about sustainable practices and environmental stewardship.


Matthew Lutz
Phone: 802-793-6363

Photo of members of the Norwich University Solar  Decathlon 2013 team standing in front of a building on campus. Enlarge image

The Norwich University Solar Decathlon 2013 team (Courtesy of the Norwich University Solar Decathlon 2013 team)

The Norwich University audiovisual presentation

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