April 11, 2008
Buildings- RISD Solar Decathlon
The Rhode Island School of design was one of 18 institutions to be selected to compete in the 2005, solar decathlon, an intercollegiate design competition sponsored by the Department of Energy. The teams, made up of students goal was to design, build and operate an 800-square foot, solar house.
RISD’s TOWN HOUSE
RISD’s entry takes the emerging practice of sustainable architecture to another level as the house will not only power itself, but will actually produce an excess of energy. The goal was to build a house that convinces visitors of the viability of solar and sustainable design and demonstrates that the aesthetics and utility of the solar house are as important as the operational technology.
The house's mechanical core differs from traditional houses in two ways: it is both more compact and expansive. The stacked organization of high performance equipment minimizes duct and pipe runs and therefore provides increased efficiency. In addition, components that extend to the envelope of the house are made up of new energy exchanging and phase change materials that react to the movement of the sun. The floor and roof do the work of old mechanical machinery to mitigate the temperature differentials.
A performative, louvered skin tracks the circuit of the sun and, according to the season, reflects or absorbs heat and provides ventilation. As the earth spins the exterior skin produces a changing visual effect through a graphic use of hidden color.
The garden utilizes a series of planter boxes in which vegetables and herbs, as well as shade plants grow. This again reduces the solar load on the building and insulates the roof. The relationship between the deck and the roof is central the townhouse concept and it was a goal to allow the garden to spill down the southern façade into a deck mounted planter, shielding the house from solar gain in the summer and providing it with solar gain in the winter when the plants are dormant.
The overriding concept for the interior is the architectural promenade – a clearly choreographed path through the house for the occupant and the visitor. The path winds through the living room, around the central core, through the home office and out onto an expansive deck, where visitors circle back where they started.
The most energy and assembly efficient component of the house is the central mechanical core. The hot water heater, the bathroom fixtures and the washer/dryer unit sit on a platform, which becomes the bathroom of the house. The bathroom shares a wall with the kitchen, minimizing plumbing runs. A fresh air supply and return fan resides above to maintain the correct humidity levels. Since the bathroom shares walls with both the bedroom and the living/dining area, ducting is virtually eliminated. The compact nature of these mechanical/ plumbing systems allows the 'core' of the building to be shipped as a unit, slid into position and hooked up in relatively short time.
Solar Energy Design
Substantial planning went into the choice of solar panels, as the house must be powered only by solar energy over the course of 10 days. After exhaustive research, the risd solar team chose Sanyo Panels. These panels produce 190 watts for each panel – a high number based on the relatively small size of the panel. The house uses 24 photovoltaic panels, which translates to the production of 4,560 watts of power at any (sunny) time of the day. The house and its solar panels have been designed to accommodate all of the appliances used during the normal course of the day.
By designing an attachment system for the panels, which can be utilized for all the major joints in the building, the assembly becomes straightforward.
This system of attachment relies not so much on the design of new pieces, but upon the implementation of existing off–the–shelf products in non-traditional use. Because the systems are modular, the number of differing pieces can be reduced to a minimum and parts can be fabricated in a simple assembly line process.
The RISD Solar house was built in Providence in modules, then disassembled and transported by Paul Arpin Van Lines to Washington, DC. Once in Washington, the house was reassembled on the Mall (the grounds of the decathelon).
The house is divided into seven modules; two at north, two at the core, and three at the south. The south and core modules are fabricated with the roof attached because of the height of the north end of the house, the roof and triangular wall sections will be shipped separately.