Valley Effect
Valley Effect is a Carbon Positive City Block that works as an ecosystem of built and natural environments. It is a terraced urban farm that provides direct connection to seasonal growth cycles, keeping its inhabitants in touch with the larger natural environment. The mass of the buildings is aligned with predominate wind patterns to create a Valley Effect that maximizes the efficiency of the site's wind turbines. The East, West and South faces of all the buildings are lined with a sun shading system comprised of over 4,880 solar panels and fiber optic light collectors. Energy consumption has been reduced by over 75% and water consumption has been cut by at least 55% for the entire site. The block produces 121% of the energy it uses.
Valley Evolution
Strawn.Sierralta designed Valley Effect as a prototype for urban living. The 2.5 acre site in Dallas, Texas is densely occupied with 500 residential units, and 75,000 sq/ft of commercial space. Solar energy modeling, site-specific wind data and year-round shadow studies were used to generate a building massing that would maximize solar collection/protection and create the needed
Valley Effect for the most optimal wind harvesting. Connection to the surrounding community is encouraged by a ground level organized with an X-shaped public plaza and a base of small businesses run by the inhabitants of the block. Important view corridors to the city are retained while the site massing responds to the adjacent City Hall.
This planning strategy, for a sustainable city block, can be adapted for any city in any climate.
Building Logic
The village of buildings forms an X-shaped public plaza that connects all interior, exterior, public and private spaces.
The X becomes the center of community life as it expands vertically and horizontally forming a matrix of terraced farmlands and gathering spaces. Three mid-rise towers grow out of the four-story plinth and open the site to views of the city and the river.
Each tower has an open-air shaft that acts as a thermal chimney. All the commercial and residential units face outward toward the city and open inward toward the shaft to allow for natural cross ventilation. This fresh air circulation will allow for the air to be turned off for up to 10% of the year.
By utilizing ground source geothermal heat pumps, in conjunction with heat recovery ventilators and super insulated hot water storage tanks, the energy needed for heating, cooling and hot water production can be reduced by 70%.
Community Building
A four-story plinth, comprised of a ground level commercial and a three story residential component, relates directly with the scale of the site's adjacent neighbors. Every unit on the first level of residential is live/work connected to a commercial space. A constructed wetland runs through the X-shaped axis of the ground level. This wetland serves as part of the water (filtration) cycle for
Valley Effect. An open-air Auditorium below the west building leads down to the Environmental Center, visitor parking and car share, connecting public spaces at the ground level and below.
Apartment Farming
All Valley Effect apartments will have direct access to 50 sq/ft of garden space, as well as, sliding brise-soleil window boxes for growing herbs and other small plants. Retaining connection to food production keeps people in touch with the larger natural systems that surround them. Every unit will also have a
Plug Out that an exercise bike with a resistance control panel will be plugged into to feed clean renewable energy back into the electrical grid. If every unit bikes for 30 minutes per week 2.6 megawatts of free, renewable green energy will be produced each year.
Fiber optic solar harvesting and redistribution will ensure that all interior spaces, including common areas outside each unit, will be lit by cool natural sunlight. All electrical light sources in the building will be either compact fluorescent or L.E.D. These steps, in conjunction with occupancy monitors, will reduce overall electrical need for lighting by 87.5%.
Apartment Axon Key: A. Fiber Optic Solar Harvesting and Distribution / B. 225 Watt PV Panel Sunshade / C. Sliding Brise-Soleil Window Boxes / D. Movable Furniture Units with Pocket Door Extensions / E. Energy Star Washer and Condensation Dryer / F. Ground Source Heat Pump for Forced Air, In-Floor Radiant Heating / G. Heat Recovery Ventilator / H. Air Plenum pulls Exhaust Air to Exterior Vertical Shaft / I. Plug-Out for Pedal Power Energy Production / J. Operable Window Walls / K. Energy Star Electrical Appliances and Low-VOC Cabinetry and Finishes / L. Exterior Stair for Community Connection / M. 50 SF+ of Garden Space per Unit
Project Data
The Big Issue:
Today 1,500 miles is the average distance produce travels to get from farm to plate. Direct connection to outdoor space for sustainable food production is necessary to encourage greener, denser urban living.
Project Description:
A speculative proposal for the world’s most sustainable block.
Concept:
A double urban valley formed by intreconnected, hollowed, terraced towers.
Year:
2009
Location:
Dallas, TX, USA
Client/Sponsor:
Re:Vision Dallas, Central Dallas Community Development Corporation, Building Community Workshop
Site:
2.5 acre, approximately 100,000 sq/ft, barren parking lot located southeast of I.M. Pei’s iconic Dallas City Hall.
Environmental Strategies:
Utilize building massing to provide for maximum open space, wind harvesting, natural ventilation and solar collection.
Program:
200 units of residential per acre (500 units total), with a portion of the units to be micro-lofts with rent cap at approximately at $450 (est. 350 sq/ft), maximum retail area of 75,000 sq/ft, an educational and a wellness component, a minimum of 50 sq/ft of arable land per residential unit, as well as, achieving carbon neutrality, zero waste and no run-off. The projects were also to achieve all published LEED points for a new construction process.
Scale:
942,410 sq/ft
Budget:
$60,000,000
Team:
Architecture: Karla Sierralta, Brian Strawn / 3D Visualization: William Turoczy
