collecting
windows sliding glass doors skylights light tubes A static, non-operable response to providing natural daylight in place of artificial indoor lighting. This provides a higher quality light, and also requires little or no energy to operate and maintain.
reflecting
light shelves lighter wall colors mirrored wall sections interior walls with upper glass panels translucent glassed hinged doors
Successful daylighting works through a balance of heat gain and loss, using collection and shading methods. Considerations such as careful siting of the building footprint, window-to-wall ratio, and daylighting-optimized fenestration design are important in creating a building that uses daylight.
Beyeler Museum Renzo Piano Basel, Switzerland
sources: http://www.wbdg.org/resources/daylighting.php http://en.wikipedia.org/wiki/Passive_daylighting http://www.architectureweek.com/2003/1105/environment
PASSIVE DAYLIGHTING STRATEGIES Case Study: NREL’s Research Support Facility (RSF), Golden CO
Energy Consumption in the United States
NREL RSF Energy Use Breakdown Data Center Data Center Fans Cooling 1% 0% Space Heating 25%
Data Center Equipment 32%
Space Cooling 3% Pumps 1%
Task Lights 0%
Ventilation Fans 6% Domestic Hot Water 3%
Source - http://www.nrel.gov/docs/fy12osti/51387.pdf Source: U.S. Department of Energy, Buildings Energy Data Book, 2006 National Renewable Energy Laboratory
Office Plug Loads 23% !!
Largest Energy Use for Commercial Buildings is Lighting at 27%
Light Louvers redirect incoming sunlight onto ceiling Light Shelf
Automatically and manually operable windows promote
reduces glare and restricts
cross-ventilation
high summer sun from entering the building
Pre-cast thermal mass wall 3” concrete 2” rigid insulation 6” concrete
glass outside
Light enters from 5° to 85°
inside
NREL took an aggressive approach at targeting energy use due to lighting. Strategies included using larger windows on the north side to capture the more diffuse light, controlling glare on the south windows with light shelves, using light louvers to redirect light onto a light colored/highly reflective ceiling, creating narrow (~60’ wide) floor plates that run east-west, and limiting partition heights within the floorspace to allow light to pass across the space. On a side note, the aluminum light shelves used are on the the interior side which protects the louvers but it also absorbs and radiates heat inside the space.
Exterior LIghts Lights 0% 6%
NREL RSF Uses Only 6% of Total Energy for Lighting
Light colored, reflective surfaces and low cubicle heights permit the penetration deep into workspaces.
Optical Louvers (section)
Light reflected up to 30° towards ceiling
Source - http://www.nrel.gov/docs/fy12osti/51387.pdf
Light enters throug the upper glass and highly reflective louvers direct it toward the ceiling and deeper into the space. Source ce - http://www.nrel.gov/sustainable_nrel/pdfs/51124.pdf
passive strategy: look at local vegetation patty gut | arista winery | russian river valley, ca
IDEA California spanish moss grows on the branches of the Coastal Live Oaks on the site. The moss has a very particular cellular pattern. The species lives by absorbing nutrients from the air and water. I am interested in the possibility of using an absorbant material in a distilled,generative pattern as a screen. By either varying the cell openings or layering iterations of the pattern, I could get different shading effects. Moss is also natural water purifier as it absorbs nutrients when water passes through. By running gray/storm water over the material there could be evaporative cooling of the building and simultaneously some water purification.
PRECEDENT Biomimicry, cellular architecture and generative formal concepts provide many different kinds of precedents.
Passive Ventilation
Passivent Airscoop - with displacement wind driven ventilation
A new educational facility to replace a Victorian school in Chesterfield is using modern environmental design to achieve light, airy and well ventilated classrooms. Research shows that pupils study better ina well-lit and well-ventilated environment.
RESEARCH Stack and wind-driven ventilation are natural mechanisms that can be addressed together since the same openings can contribute to both effects in a building, though they do not depend on the other. In stack ventilation, air is driven by vertical pressure differences -- a result of thermal buoyancy, or stratification. Warm air inside the building is less dense than cooler air outside, and escapes by openings high up in the envelope. Cooler, denser air enters openings lower down. The process continues as supply air is heated, often by casual or solar gains. PRECEDENT M cCann Fitzgerald Office, Dublin, Ireland, uses a double-skin facade application to create stack ventilation in the multi-storied building.
WIND-DRIVEN + CROSS VENTILATION The wind hits the windward wall causing a direct positive pressure. The wind moves around the building and leaves the leeward wall with a negative pressure. STACK EFFECT + STRATIFICATION There is a cooler zone at the bottom, which contributes to the thermal comfort of occupiable spaces. The upper zone may experience unwanted heat gains.
For wind-driven ventilation, consider the building shape, orientation, and location, as these factors create wind pressures that drive air flow. Choose a location with a lot of wind, orient the building so the windward wall is perpendicular to predominant winds. Naturally ventilated buildings should not be too deep as it is more difficult to distribute fresh air to all parts of a building. Operable windows/louvers/dampers are important for occupant control of thermal comfort. Placed on opposite sides and heights of a space, they allow for cross ventilation. Ideally a space should have both cross and stack ventilation. RESOURCES
WIND-DRIVEN + STACK VENTILATION
PASSIVE SYSTEM
Getting Aggressive About Passive Design, Russell Fortmeyer, Architectural Record, May 2007. Accessed 3/24/13. http://continuingeducation.construction.com/article.php?L=5&C=208. Natural ventilation: stack ventilation, Nick Baker, Royal institue of British Architects. Accessed 3/24/13. http://www.architecture.com/SustainabilityHub/Designstrategies/Air/1-2-1-2-Naturalventilation -stackventilation.aspx. Natural ventilation: stack ventilation, Andy Walker, National Renewable Energy Laboratory, Whole Building Design Guide, 6/15/10. Accessed 3/27/13. http://www.wbdg.org/resources/naturalventilation.php.
PASSIVE.Windcatchers.Downward Flow.Upward Flow (Solar and Wind Temperature Gradients) Kenyon Duncan Windcaters can be used in most building types in most climates. They are primarily used for ventilation in warm climates. Downward Flow Most common use of windcatcher Tall capped tower open to prevailing wind Forces ventilation air into interior of building Relies on rate of airflow to cool Upward Flow - Wind-assisted Tall capped tower open away from prevailing wind Pressure differential pulls air out of tower Ventilation air enters building at designers choice Used with underground water to cool air Upward Flow - Solar-produced Used with solar chimney to heat air Heated air escapes tower and pulls cool air Ventilation air enters building at designers choice
Zion National Park Visitor Center Completed May 2000 - 7,600 square feet - Zion, Utah Building has two downward flow windcatcher towers with evaporative cooling pads to condition ventilation air. Windcatchers are used in conjunction with passive solar heating, thermal massing, and a Trombe wall to create significant energy savings.
Resources: http://buildingdata.energy.gov/content/zion-national-park-visitor-center-1 http://en.wikipedia.org/wiki/Windcatcher
natural ventilation Cross Ventilation
LEEWARD SIDE
Wind-induced ventilation uses pressures generated on the building by the wind, to drive air through the openings in the building. It is most commonly realised as cross-ventilation, where air enters on one side of the building and leaves on the opposite side. But there are options in single side ventilation, and vertical ventilation flows.
WINDWARD SIDE
EXHAUST AIR
Stack Ventilation Stack ventilation is where air is driven through the building by vertical pressure differences developed by thermal buoyancy. The warm air inside the building is less dense than cooler aif outside, and thus will try to escape from openings high up in the building envelope; cooler denser air will enter through openings lower down. COOL AIR
COOL AIR
Pressure Zones NEGATIVE PRESSURE ZONE
POSITIVE PRESSURE ZONE
Zion National Park Visitor Center, UT Uses cooling towers to bring cool air into the buidling.
NEGATIVE PRESSURE ZONE
POSITIVE PRESSURE ZONE
research
• A trombe wall is an indirect solar heating and cooling method using thermal mass, solar gain, and solar glazing • Consists of a (usually dark-colored) wall with high thermal mass, such as a masonry wall, facing the sun (usually to the south). Glazing on the exterior of the wall traps warm air in the space between the glazing and the wall • Vents at the top and bottom of the wall allow for air circulation and convection currents, which allow cool air in the room to escape at the bottom and warm air to enter the room • For an 8”-thick trombe wall, heat takes about 8 to 10 hours to reach the interior of the building; rooms receive slow, even heating for many hours after the sun sets, reducing the need for conventional heating
PRECEDENT: Recreation & Wellness Center, Hayward Campus, California State University uses a ventilated trombe wall; designed by LPA Inc.
Trombe wall construction detail
• Rooms heated by a trombe wall often feel more comfortable because of the warm surface providing radiant comfort • A successful trombe wall optimizes heat gain, minimizes heat loss during cold periods, and avoids excess heat gain during hot periods
PASSIVE STRATEGY
radiant heating & cooling: trombe wall REFERENCES Adobe Bricks in New Mexico, by Edward W. Smith, CIrcular 188, New Mexico Bureau of Mines and Mineral Resources, 1982 https://wiki.ucfilespace.uc.edu/groups/11a_20artn319001/wiki/f4438/ http://sustainabilityworkshop.autodesk.com/buildings/trombe-wall-and-attached-sunspace http://www20.csueastbay.edu/af/departments/facilities/design/sustainability/construction_projects/
The workings of a trombe wall and convection currents
What is it?
Precedent
Geothermal systems use the constant temperature underground in order to passively heat and cool buildings. They do this by burying tubes underground filled with liquid or air and then circulating that fluid in order to exchange temperatures with the building above the surface. During hot days the heated liquid travels underground, is cooled by the ground, comes back to the surface and is used to cool the building. A geothermal pump uses collector loops to obtain the cooling and heating properties without using additional energy. It can then be dispersed through the ductwork.
Strategic Energy Solutions (SES) engineering firm in Michigan utilized this system in their new 9,000sq ft LEED gold headquarters. They bored 16 holes 200ft deep to heat and cool their building and the cost was comparable to a HVAC system of equal value. They have saved 42% of the energy cost of the building and about $6,000 a year in energy savings. They received a tax credit for the system and saw a return on investment in about 10 years.
Benefits This system provides an energy efficient way of heating and cooling a building through the use of the land it sits on. This removes its dependency on outside sources of fossil fuels. It can cut out as much as 2/3 of heating and cooling costs The system requires very little maintenance, allowing it to last anywhere from 25 to 50 plus years. The constant underground temperature creates a reliable system that can work all day, every day. California has a higher underground temperature due to the seismic activity in the area. It also creates constant air flows, unlike traditional systems that blow air through ducts in bursts. They can also have a payback period of about 10 years.
Drawbacks They can have a higher initial cost over traditional HVAC systems but this isn’t always the case. Another drawback is also a benefit, and that is the seismic activity. Deep drilling in seismic areas has caused earthquakes so the location needs to be studied before drilling. They also require a large amount of space underground, so acreage is important and in certain areas of the world the ground temperature is not high enough for geothermal. Also, if overworked an area’s underground temperature can drop and the geothermal energy is no longer useful.
This map shows the estimated temperature of the ground 3.7 miles (6 kilometers) under the surface. Red is 392 degrees Fahrenheit
SES geothermal holes Sources http://buildipedia.com/aec-pros/construction-materials-andmethods/roi-behind-geothermal-systems http://www.popsci.com/science/article/2010-03/doesgeothermal-power-cause-earthquakes http://www.boreal-geothermal.ca/geothermal-heat-pump-passive-heatingcooling.html http://greenpassivesolar.com/sustainable-renewable-energy/geothermal-energy/ http://www.doityourself.com/stry/how-to-set-up-a-passiveheat-pump-cooling-system#b
Passive Geothermal Passive System