Post on 03-Mar-2016
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UNDERGRADUATEARTS + HUMANITIESCollege of Arts, Media, and DesignBachelor’s of Arts in ArchitectureAbstract ID #210
COOLING TOWERraised ventilation tower is aligned with the prevailing winds during te summer months, and allows augmented natural ventilation, in combination with an indrect cooling membrane.
THERMAL MASSING STRATEGY
by burying the structure deep into the earth and using concrete walls + roof, we can ensure that the maximum amount of thermal heat is absorbed, and then released during a night purge.
SUN BLOCKING CANOPYall south-facing overhangs extend to ensure that during the hottest months, no direct sunlight will enter the structure, while also allowing sunlight to penetrate during the winter.
SECONDARY CROSS VENTILATIONoperational/moveable system that allows for a proper cross ventilation that would facilitate the cooling of the structure during the night (night purge). ideally not operational during the day when the cooling tower would be in effect because it would deviate the hot air from accumulating in the tower.
WEST ELEVATIONSOUTH ELEVATION EAST ELEVATIONNORTH ELEVATION
FLOOR PLANS NORTH - SOUTH SECTION
5 10 30
NIGHTair flow removes heat gained by slab during the day and purges it
DAYcooling tower drawshot air outstratification
hot/dry airis not allowedinto the building
DAYcool/dry airpurges heatand ventilates
NIGHT
“2H” rule:H taken at 20’
“15, 30” diagramdarker yellow indicates the “adequately”daylighted zone (15-30 feet)
“15, 30” diagramdarker yellow indicates the “adequately”daylighted zone (15-30 feet)
mechanical ventilation 24-hour mechanical cooling
night purge vetilation (10pm - 4 am) mechanical cooling (4am - 10pm)
night purge vetilation (10pm - 4 am) mechanical cooling (4am - 10pm)
exterior in july: 98°interior in july: 78°
exterior in december: 55°interior in december: 75°
night purge vetilation (10pm - 4 am) mechanical cooling (10am - 10pm)
TEST 1: SELECTED METHOD:
AVG. AMBIENT TEMP:
TEST 2:
TEST 3:
TEMPERATURE COMPARISON with selection
ENERGY USE COMPARISON with selection
ENGERY CONSUMPTION (kBTU)
0
20
40
60
80
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120
140
APRIL JULY OCTOBER
TEMPERATURE (Fahrenheit) INDOOR OUTDOOR
40APRIL JULY OCTOBER
60
80
100
ENGERY CONSUMPTION (kBTU)
0
20
40
60
80
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120
140
APRIL JULY OCTOBER
INDOOR OUTDOORTEMPERATURE (Fahrenheit)
40APRIL JULY OCTOBER
60
80
100
ENGERY CONSUMPTION (kBTU)
0
20
40
60
80
100
120
140
APRIL JULY OCTOBER
INDOOR OUTDOORTEMPERATURE (Fahrenheit)
40APRIL JULY OCTOBER
60
80
100
39PANELS
X3911.7 KW
DC rating
DC to AC derate factorAC ratingArray typeArray TiltArray AzimuthElectricity cost
11.7 kW.770
9.0 kWFIXED TILT
18.5180
8.5 cents/kWh
18,498 kWhYEARLY
15.4 years
The “overheated” period in Phoe-nix, Arizona represents the great-est portion of the days that fall out of the original comfort zone for the climate.
Therefore, the most attention should be paid to improving the conditions during this period.
A hot-button topic at Northeastern University is the “go-green” phenomenon, which raises questions regarding how we treat the world in which we live. Although sustainability is an issue that has global implications, it is nonetheless one that can be confronted at the micro-scale. Currently, the construction and maintenance of our buildings is accountable for 48% of global carbon dioxide emissions. This includes not only the heating and cooling costs and the embodied energy released by moving materials to a site, but also the performance of those materials once the building is finished. As architecture stu-dents, we realize that the onus is on us to make choices to ensure that our buildings can be part of a future, rather than the ruins of a past.
A recent Environmental Systems class began to show us ways to make these environmentally conscious choices through-out the design process. During the semester we faced weekly challenges regarding the design of the different systems of a “sustainable” house, sited in Phoenix, Arizona. The final investigation was the use of energy-modeling simulations, which allow the architect to understand the effectiveness of their design, and help guide decisions made regarding material choices and HVAC systems.
Despite only an experimentation with these programs, the results were promising and verified that the house functioned as intended. I believe a longer exposure to energy simulators such as DesignBuilder would result in significantly more sustain-able designs, not only in my work, but for the entire Northeastern Architecture program altogether.
Located in Phoenix, Arizona, the site presented many challenges in the design of an environmentally concious residence. When designing with passive systems, it is important to understand where the most effective application of such moves can be most beneficial. The first step was to research how the natural conditions of Phoenix would affect the systems that we would employ, to maintain an energy effecient home. The hot, dry climate requires an emphasis on cooling strat-egies during the day, but the temperature often drops off at night, requiring some heat-retention strategies as well. Below are two icons which we developed as a jumping point from which to better understand how to apporach this design.
Most temperatures during the “under heated” period of the year in Phoenix fall well within the com-fort zone of an average human, and never approach 32° F.
The best passive technique is to live according to your climate - ADAPT!
N15°
30°
45°
60°
75°
90°
105°
120°
135°
150°
165°180°
195°
210°
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255°
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10°
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8910111213141516
171st Jan
1st Feb
1st Mar
1st Apr
1st May
1st Jun1st Jul
1st Aug
1st S ep
1st Oct
1st Nov
1st Dec
the main goal is keep-ing direct sunlight outside during the hot months.an operational porch roof allows sunlight inside during the winter.the cooling tower works as a clerestory for winter light.main roof inclinations and overhangs were determined by two sample moments in the year (July 21, December 21).
following the idea of night purge and natural ventilation, the prevailing winds on site were studied.the most regular wind orienta-tions where grouped and the orientations (degrees) where averaged, both, the yearly data, and July’s (hottest month) data, to finally come up with an appropriate 20 degree rotation angle in plan to collect the best winds for the desired passive systems.prevailing wind information could potentially further inform the design of the vents that serve the night purge system.
the psychometric chart helped inform early decision on the design agenda and strategies.the study resulted on a reinterpretation of the way in which the passive strategy’s effectiveness on expanding the comfort zone of a deter-mined space is read in the psychometric chart - the comfort percentage scale.knowing the most effective strategies on helping accomplish the early objec-tives of the project prevents design decision that are not the best possible and creates a more comprehen-sive design overall.
PSYCHOMETRIC CHART & PASSIVE STRATEGIES STUDY PREVAILING WINDS STRATEGY AND DESIGNSOLAR ORIENTATION STRATEGY AND DESIGN
12:00 (11:34) 172.9° 32.7°12:30 (12:04) -178.9° 33.0°13:00 (12:34) -170.7° 32.5°
12:00 (11:28) 144.0° 77.6°12:30 (11:58) 177.9° 79.7°13:00 (12:28) -147.1° 77.9°JU
LY21
DE
C21
time solar azimuth altitude
N O R T H1 5 °
3 0 °
4 5 °
6 0 °
7 5 °
E A S T
1 0 5 °
1 2 0 °
1 3 5 °
1 5 0 °
1 6 5 °S O U T H
1 9 5 °
2 1 0 °
2 2 5 °
2 4 0 °
2 5 5 °
W E S T
2 8 5 °
3 0 0 °
3 1 5 °
3 3 0 °
3 4 5 °
10 km/ h
20 km/ h
30 km/ h
40 km/ h
50 km/ h
prefered orientation (year)
N O R T H1 5 °
3 0 °
4 5 °
6 0 °
7 5 °
E A S T
1 0 5 °
1 2 0 °
1 3 5 °
1 5 0 °
1 6 5 °S O U T H
1 9 5 °
2 1 0 °
2 2 5 °
2 4 0 °
2 5 5 °
W E S T
2 8 5 °
3 0 0 °
3 1 5 °
3 3 0 °
3 4 5 °
10 km/ h
20 km/ h
30 km/ h
40 km/ h
50 km/ h hrs
42+
37
33
29
25
21
16
12
8
<4
prefered orientation (july) DBT (°C) 5 10 15 20 25 30 35 40 45 50
AH
5
10
15
20
25
30
NATURAL VENTILATION
DE
C
JAN
not the most effective passive strategy, but it is indispensable for a proper thermal mass/night purge strategy.the plan was rotated 20 degrees by averaging the angle of prevailing winds from the whole year with the data of July (least comfort zone month).the secondary ventilation screen system provides proper cross ventilation to the double height space.the screens (on the East and West facades of the structure) would be open to allow the night purge of the building mass, but closed during the day so that thecooling tower could function to its best performance.
THERMAL MASS + NIGHT PURGE
JAN
DE
C
most effective passive strategy.effective in both winter and summer.material changed (concrete) and massiveness of the structure was increased to allow for heat sink and night purge.use of natural ventilation to allow for proper night purge is allowed with secondary cross ventilation.burrying the structure in the slope allows for better insulation, still the thick slab that roofs the double height space works as a thermal mass for the structure.
INDIRECT EVAPORATIVE COOLING
DE
C
JAN
second most effective passive strategy.indirect cooling tower is applied in the structure to effectively apply inderect evaporative cooling.hot air would rise and end up accumulating in the cooling tower which has been designed with screens that allow proper air circulation to drive the hot air outside.the secondary (operational) ventilation screen does not interfer with this system since it would be used for night purge only (or when extreme windy conditions makecross ventilation more effective than indirect evaporative cooling).
DIRECT EVAPORATIVE COOLING
DE
C
JAN
not as effective as indirect cooling. not considered in any of the strategies followed in the structureif needed strategies could be followed.
PASSIVE SOLAR HEATING
DE
C
JAN
not the most effective passive strategy.sun must be a driver of design even if it is not the must effective strategy.the operational roof structure in that covers the porch was desgned with the proper angles that allow winter sunlight in, and keep sun outside the rest of the year.the overhang of the mezanine follows the intent of allowing winter sunlight inside as much as possible. the cooling tower becomes a hybrid, it also works as a clerestory, designed to allow the must winter light inside, and thus, solar radiation.direct solar “cooling” - thinking ahead (in active systems) the massive roof over the double height space follows a 18.5 degree angle that corresponds to the angle PVs must follow for the optimal sun recolection for solar cooling.
0% 100%
COMFORT PERCENTAGE SCALE (monthly)beforeafter
PHOENIX PAVILIONKYLE BIRCHALL | JOSE LATORRE | ACADEMIC ADVISOR | SETH HOLMES
RESEARCH IN ENERGY MODELING AND SUSTAINABLE DESIGN
PROJECT ABSTRACT
ARCHITECTURAL DRAWINGS DESIGN DIAGRAMS PHOTOVOLTAIC PANEL STUDY
ENVIRONMENTAL SYSTEMS PRIORITIES ENERGY MODELING DATA (using DesignBuilder)
PRESENTED PROBLEM