low energy air circulation
Mason Residence Tectonic Design Moorsville, North Carolina [pool in courtyard utilized in evaporative cooling]
Evaporative cooling uses fans to draw in dry, outdoor air, which is then misted with water and allowed to evaporate. As an active system, this type of cooling is still relatively low energy with a high degree of efficiency. Due to the use of outside air, evaporative cooling serves to increase fresh air circulation within the building. This system also requires less ductwork than traditional air conditioning, making it less expensive and easier to install.
Prineville Data Center Sheehan Partners Prineville, Oregon sources: http://inhabitat.com/facebooks-energy-efficient-prineville-data-center-in-oregon-achieves-leed-gold-status/prineville-data-center-sheehan-partn ers-6/ http://www.consumerenergycenter.org/home/heating_cooling/evaporative.html http://www.archdaily.com/123540/mason-residence-tectonic-design/
research
• Geothermal energy is derived from the heat in the earth’s interior; it comes from the decay of radioactive elements in the earth’s crust as well as heat from the sun that is absorbed and stored in the earth • Geothermal energy can be utilized through direct/hydrothermal means or ground source heat pumps (GSHP) • Hydrothermal energy exists in hot springs, geysers, and dry steam; hydrothermal reservoirs can be used to directly heat residential, industrial, and commercial buildings • GSHPs are electrically powered heat pumps that consist of pipes buried underground near the building, ductwork in the building, and the heat pump. The heat pump can provide both heating and cooling
PRECEDENT: Kramer/Mimnaugh Residence, Denver Highlands Sustainable Home Project, Denver, CO; designed by Merten, Inc.
How to heat with near-surface geothermal energy
• Heat pumps draw heat into a building from outside during the heating season, and expel heat from a building to the outside during cooling season; the pump drives heat from a low to high temperature using vapor-compression refrigeration
ACTIVE STRATEGY
geothermal heating & cooling REFERENCES Mechanical and Electrical Systems in Architecture, Engineering, and Construction, by Joseph B. Wujek and Frank R. Dagostino, Prentice Hall, 2010 http://www.ucsusa.org/clean_energy/our-energy-choices/renewable-energy/how-geothermal-energy-works.html http://www.unendlich-viel-energie.de/en/homepage/details/article/19/functioning-principles-of-a-near-surface-geothermal-energystation.html http://kramerconcepts.com/
active strategy: solar hot water system patty gut | arista winery | russian river valley, ca
PRECEDENT The Solar Umbrella House in Venice, California uses a solar hot water system to heat the concrete floors throughout the home’s addition.
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SUNSHINE LEVELS IN % OF HOURS?DAY WITH SUN IDEA The climate of the site is well-suited for a solar hot water system. First of all, the site has high levels of solar exposure. I am placing the building near the top of the hill and away from the shade of the Oak tree grove. Furthermore, there is potential for a gray water system working in conjunction with water purification and the solar hot water system.
ACTIVE.Concrete Core Temperature Control (CCTC) Kenyon Duncan
Energon PassiveOffice Building Completed October 2002 - 8,266 square meters - Ulm, Germany For heating and cooling, the building primarily uses concrete core temperature control. For the purposes of concrete core temperature control, plastic tube heat exchangers with a surface area of around 5,000m² are laid with 10cm clearance from the underside of the flooring. For temperature control, the 40 borehole heat exchangers protrude about 100m deep into the ground. Within them, water flows in a closed circuit that comprises the borehole heat exchangers and the tube heat exchangers. Thus, the ground functions as heat storage or cold storage, and the bivalent utilisation supports thermal regeneration.
Resources: http://www.enob.info/en/new-buildings/project/details/energon-passive-office-building/ Temen Info 2007: A Compact Guide to Energy Research. Thermo-active Building Systems. BINE Informationsdienst
Active System Photovoltaics
1st generation - chrystalline silicon, maximum efficiency 31%-41% (Shockley-Queisser limit), expensive. 2nd generation - thin film, less expensive, less efficiency 3rd generation - lower embodied energy, greater efficiency, lower costs. Total embodied energy payback time approaching 2 years.
Solar Tracking - Passive: imitate the way plants track the sun across the sky, by using the difference in temperature between shaded and sunny areas to change the properties of the material supporting solar photovoltaic cells. The system, once built, is completely passive, requiring no power source or electronics to control the movement. Solar cells that track the angle of the sun can be 38 percent more efficient at generating power than those that are mounted in a fixed position,
http://web.mit.edu/newsoffice/2008/madmec-0919.html http://www.mse.berkeley.edu/~jwu/publications/Brown-LPR-09.pdf Green Bulding Resource Guide Vol. 4, UCDenver 2009 http://www.pvthin.org/
PV Cells PV cells are the basic building blocks of PV modules. They are made of semiconducting materials, typically silicon, doped with special additives. Approximately 1/2 volt is generated by each silicon PV cell. The amount of current produced is directly proportional to the cell’s size, conversion efficiency, and the intensity of light. As shown in the figure below, groups of 36 seriesconnected PV cells are packaged together into standard modules that provide a nominal 12 volt (0r 18 volts @ peak power). PV modules were originally configured in this manner to charge 12-volt batteries. Desired power, voltage, and current can be obtained by connecting individual PV modules in series and parallel combinations in much the same way as batteries. When modules are fixed together in a single mount they are called a panel and when two or more panels are used together, they are called an array. (Single panels are also called arrays.)
PV has come a long way. Monocrystalline silicone modules (the most efficient readily available product) of over 20% efficiency are now available. Amorphous silicone PV (thin-film or a-si) are also very popular because of their use in Building Integrated PV (BIPV) products and their lower manufacturing costs. A-si PV can also continue to produce electricity when partially shaded, an advantage over mono- and polycrystalline silicone. However, a-si does have significantly lower efficiency rates. Some BIPV applications are shown below and to the right. Walkable PV Roof (Onyx Solar)
DENVER FEDERAL COURTHOUSE
Photovoltaic (PV) Systems PV Product: Size: Projected System Electrical Output: Gross PV Surface Area: PV Module Weight: PV Cell Type: PV Efficiency: PV Module Manufacturer:
Custom-sized BIPV glass laminate 15 kWp (roof ); 3.4 kWp (skylight) 20,150 kWh per year (roof ); 4,700 kWh per year (skylight) 172 m 2 (roof ); 59 m 2 (skylight) 4,661 kg (roof ); 2,749 kg (skylight) Single- or polycrystalline silicon 10% or greater Pilkington Solar
The Photovoltaic Effect Sunlight is composed of photons—discrete units of light energy. When photons strike a PV cell, some are absorbed by the semiconductor material and the energy is transferred to electrons. With their new-found energy, the electrons can escape from their associated atoms and flow as current in an electrical circuit. PV arrays require no care other than occasional cleaning of the surfaces if they become soiled or are used in dusty locations. However, they must be kept clear of snow, weeds, and Light other sources of shading to operate properly. energy PV cells are connected in series, so shading even one cell in a module will appreciably decrease the output of the entire module.
n-Type semiconductor p-Type semiconductor Photovoltaic device
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http://www.onyxsolar.com Ventilated PV Facade (Onyx Solar) SML solar house
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http://onyxgreenbuilding.wordpress.com
Eiffert & Kiss, “Building-Integrated Photovoltaic Designs for Commercial & Institutional Structures, A Sourcebook for Architects” www.nrel.gov/docs/fy00osti/25272.pdf (accessed March 25, 2013)
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What is it?
Precedent
Photovoltaic systems utilize panels made up of solar cells to convert solar energy into electricity. These solar cells are combined into modules, which are linked together to create arrays. Linking many cells together increases the amount of power a system can produce. The electricity collected by these panels can be used immediately or stored for use during the night or cloudy days with the use of batteries. These systems can be fixed at specific angles or allowed to rotate to follow the sun’s movement. The Flat-Plate system is the most common due to its ability to absorb both diffuse and direct sunlight.
Dutcher Crossing Winery uses solar energy to power their winery and a residence. They used 195 170 watt panels to produce 33 kilowatts of power. This system takes up 2,680sq ft of space and generates enough energy to power 14 homes a day. It was designed to repay itself in 6 years and eliminates the need for electricity during peak uses and creates excess electricity it sells to the utility company, which allows them to utilize it during nights at winters when the sun is not as productive. Flat-Plate System
Benefits There are no moving parts in the assembly, which lowers the amount of maintenance required. They are small profile and can fit in like shingles on a roof. They greatly reduce the amount of electricity a building requires from outside sources. The panels can be configured to mount of many different surfaces and can be adjusted to different angles during the year, as well as utilize a solar tracking system. They generate 3 to 6 times more energy than required to produce them. They also limit fossil fuel consumption. They convert on average 17% of sunlight they absorb into electricity. Owners can receive rebates for purchasing them.
Drawbacks They have a high initial cost. They require batteries to store electricity for later use, which reduces the stored energy by 20%.These batteries are bulky and take up space. A large area can be needed for the necessary amount of solar panels. Fixed panels are much less efficient than solar tracking panels, but the tracking panels cost much more and have moving parts which require extra maintenance
Dutcher Crossing
Sources http://exploringgreentechnology.com/solar-energy/advantagesand-disadvantages-of-solar-energy/ http://css.snre.umich.edu/css_doc/CSS07-08.pdf http://www.solarcraft.com/assets/solar-case-studies/csdutcher-crossing-solar-power-winery.pdf http://www.eere.energy.gov/basics/renewable_energy/photovoltaics.html
Photovoltaic Panels Active System
RESEARCH Operable shading systems adjust louver position to provide the most effective shading. Typically, multiple banks of louvers are operated by linear actuators through a system of levers and push rods or by rotary actuators through a system of worm gears. Some systems employ a weather station that may include a luz sensor for brightness, wind speed sensor, water (rain/ice/snow) sensor, and outside air temperature sensor.
PRECEDENT New York Times Headquarters, New York City, NY, Renzo Piano.
LOUVER ANGLE Optimal shading for particular sun angles [left]. OPERABILITY + MECHANICS Louver banks controlled by [1] linear actuators with a system of levers and push rods, or [2] by rotary actuators through a system of worm gears [center]. Weather station [right].
External systems regulate building temperatures and reduce the need for air conditioning by controlling incident solar energy before it enters the building envelope. Internal shading systems allow occupants to control daylight and glare. Louver configuration determined by facade orientation: Louvers for south-facing elevation are typically specified horizontally and can be positioned to provide optimal shading for a given sun angle. On east and west elevations, louvers are vertical to provide shading for lower sun angles. Materials include glass, wood, plastic, metal, etc. A wide range of louver profiles, sizes and surface designs/treatments exist to provide varying aesthetic and performance features. RESOURCES
MECHANICAL + AUTOMATED LOUVERS
ACTIVE SYSTEM
Solar Shading Louver System, Mestek Architectural Intelligent Envelopes. http://mesteksa.com/fileuploads/Literature/PartnerAccounts/1614/ColtSolarShadingLouverSys temsBrochure.pdf Sun Louvers, Nysan Solar Control, Hunter Douglas, Inc., Alberta, Canada: 2007. http://www.nysan.com/documents/solarcontrol/sunlouvers/aerofins/NysanSunLouversBrochur ev2.pdf
Active Daylighting
Sundolier Systems - Vertical systems
How It Works The SundolierŽ daylight harvester actively tracks the sun from sunrise to sunset delivering 100,000 lumens of natural light. The harvester concentrates and collimates sunlight so that it can be brought deep into the core of your building. A small roof penetration (2’, 0.6m) eases retrofit installations, offering a sustainable, healthy, daylighting solution for existing buildings or new construction. Once inside, daylight is indirectly distributed to large areas without hot spots or glare, using one of our unique in-room fixtures. Additionally, we offer collaborative design assistance for more specific needs, as well as an array of customizable options such as modular LED 'hybrid' lighting, and integration of photovoltaic panels for a completely self-powered solution.
living roof A living roof or green roof is a roof of a building that is partially or completely covered with vegitation. Green roofs serve several purposes for buildings such as:
VEGETATION GROWING MEDIA FILTER LAYER
absorbing rainwater providing insulation creating a habitat for wildlife helping lower urban air tempuratures There are two types of green roofs: intensive roofs, which are thicker and can support a wide variety of plants but are heavier and require more maintenance, and extensive roofs, which are covered in a light layer of vegetation and are lighter than an intensive green roof.
Green roof system California Academy of Science in San Francisco, CA
DRAINAGE LAYER PROTECTION FABRIC ROOT BARRIER INSULATION WATERPROOFING MEMBRANE ROOF DECK
ASSEMBLY
Green roof system CYAN PDX Apartments in Portland, OR