LAS VEGAS BALANCING ACT Centennial Hills Transit Center • Las Vegas, Nevada Energy Performance Analysis and Redesign Proposal 1
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LAS VEGAS BALANCING ACT Centennial Hills Transit Center • Las Vegas, Nevada Energy Performance Analysis and Redesign Proposal
Lee Jorgensen Arch 510 Reynolds 12.7.2011
ABSTRACT The Centennial Hills Transit Center in Las Vegas presents an interesting case to analyze and propose passive heating and cooling retrofits to this existing structure. The structure was completed in 2010 and is intended to serve as a recognizable public transit park and ride hub adjacent to Interstate 95 for commuters heading to Las Vegas downtown. Las Vegas’ hot and dry climate presents opportunities as well as challenges when looking to passively heat or cool a building. Opportunities include a terrific solar resource, a dry climate with relatively large temperature swing between day and night, and mild winters . The primary challenge for this climate is the extreme heat in the summer, evident in the 106°F summer dry bulb design temperature. In addition to the unforgiving summer climate, the function of the building as a transit center means large occupant loads during peak use and therefore significant internal heat gain. Reconciling these factors would be challenging enough in a typical building, but here the client desired a very transparent structure for both safety reasons and to allow for visual connection to busses arriving. A significant amount of glass was used in the original design to help achieve this. The three main design changes resulting from the heating and cooling analysis are a reduction in the amount of glazing, the incorporation of solar into shading devices, and the addition of a cooltower. In addition to these major interventions, a number of other design changes help maximize direct gain for winter heating and reduce the summer dependence on air conditioning to only ten percent. These proposals include installing a heat exchanger to reduce winter lung losses, insulating the floor slab, and adding operable windows for natural ventilation during the milder seasons. Together, these strategies allow The Centennial Hills Transit Center to rely less on the mechanical system for heating and cooling and provide an example for future public facilities in the area.
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PHASE 1 Identify the building and analyze its climate. The Centennial Hills Transit Center was completed in 2010 and serves as the primary transit center for commuters in the Centennial Hills area taking the express bus to downtown Las Vegas. Key elements of the transit center include:
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1,720sf transit center (2) Rest Rooms (2) Offices Passenger waiting Primary building materials – stone, concrete, glazing, zinc Approximately 900 surface parking spaces for cars Transit shelter & transit bays for future express transit service and local routes; and Security staffed full-time
With Las Vegas’ hot and dry climate, the opportunity to incorporate passive heating and cooling strategies greatly increases. However, the building was designed with relatively little energy performance analysis and will make for an interesting analysis and potential redesign proposals.
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Existing Conditions
View From Southeast
View From East
Interior View
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SITE PLAN
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TRANSIT CENTER FLOOR PLAN 5
1 • NORTH ELEVATION
2 • SOUTH ELEVATION
3 • EAST ELEVATION
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4 • WEST ELEVATION
Provide a cooling strategy analysis
Potential Cooling Strategies: • High Mass Cooling with night ventilation. - The current design has stone flooring and heavy mass stone walls that can be utilized for high mass cooling with night ventilation. However, glazing makes up a significant part of the envelope. I anticipate that some glazing will need to be replaced with mass to reach the overall level of mass needed. • Evaporative Cooling - Two existing vertical walls extend beyond the roof plane and serve as focal points for the adjacent interstate traffic. The core of the building created by these walls could serve as an evaporative cooling tower and serve as a vertical element that helps passively cool the building. • Cross and Stack Ventilation - During the spring and fall temperatures are mild and cross or stack ventilation could be used. A point to explore further is the prevailing winds and how this method interacts with the bus queuing zone to the south of the transit center. • Conventional Air Conditioning - A limited amount of conventional air conditioning will need to account for the high humidity cooling days.
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PHASE 2 Band of Sun Analysis Las Vegas has extremely hot and dry summers and relatively mild to cool winters. Shading and reducing solar heat gain during the summer months is imperative for a successful passive strategy. With an abundance of sun, the site also has great opportunities for solar production. Because of the facility’s program and function as a transit center, transparency was extremely important to the client. Therefore, extensive glazing was used on the southern facade as well as some glazing on adjacent facades. This was to allow for visual connection in and out of the transit center for both safety and user convenience reasons. With the vast glazing walls, shading is even more critical, as is assessing if this extent of glazing is truly necessary.
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Potential for solar awning production with reduced overhang.
Sola r Pho tovo Sun l Sha taic de
EXISTING
REDESIGN
BAND OF SUN ANALYSIS SUMMER SOLSTICE • AT SECT 6 Summer shading in Las Vegas’ hot climate is imperative. An extensive south-facing glazing wall was desired for visual connection to the bus loading platforms, and this wall must be shaded appropriately to reduce summer heat gains. The existing four foot overhang and sun shade adequately shade the southern glazing wall.
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The redesign reduces the glazing by raising the opaque sill height. Also, the sun shade’s maximum potential is realized by pulling back the four foot overhang and installing solar panels on the shading device. While this would result in a small amount of production (approx. 2kW), it would help brand the building as sustainable and provide energy for items such as the ticket vending machines. 9
EXISTING
See-thru solar PV glazing
REDESIGN
BAND OF SUN ANALYSIS FALL/SPRING EQUINOX • AT SECT 6 The fall equinox in Las Vegas still experiences hot weather, and will most often benefit from shading of the south glazing wall. During the spring equinox, this solar gain is more helpful, but temperatures are still relatively mild at that time of year. Therefore, it is reasonable to prioritize shading over solar gain for the equinox cycles. The existing scheme accomplishes this by utilizing the 4 foot overhang and sun shade. The light shelf accompanies the sun shade, and while it has less of an impact on solar gain, it helps distribute light deeper into the building.The redesign reduces the overhang and incorporates see-thru solar glazing on the south facade and a solar shading device. Micro-inverters should be considered for the PV to reduce the effect of partial shading. 10
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BAND OF SUN ANALYSIS WINTER SOLSTICE • AT SECT 6 The relatively deep transit center and four foot roof overhang combined with the southern shading device block approximately 50 percent of the sun on the winter solstice at noon.
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The reduced overhang on the redesign maximizes this gain while respecting the summer shading devices. The solar gain is balanced with see-thru solar glazing to utilize the excess solar resource during the winter. The large number of days with sun in Las Vegas and the positive effect cool temperatures have on the efficiency of solar panels makes solar a reasonable choice for Las Vegas winters.
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Potential for solar awning production with reduced overhang.
Sola r Pho tovo Sun l Sha taic de
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BAND OF SUN ANALYSIS SUMMER SOLSTICE • AT SECT 7 Again, the extensive south-facing glazing wall was desired for visual connection to the bus loading platforms, and this wall must be shaded appropriately to reduce summer heat gains. The four foot overhang takes care of all of the shading for the glazing wall along the portion of the building with a lower roof. The redesign takes similar steps shown at section cut 6, including raising the opaque sill height, reducing the four foot overhang, and incorporating solar panels into the shading device.
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EXISTING
See-thru solar PV glazing
REDESIGN
BAND OF SUN ANALYSIS FALL/SPRING EQUINOX • AT SECT 7 The fall equinox in Las Vegas still experiences hot weather, and will most often benefit from shading of the south glazing wall. During the spring equinox, this solar gain is more helpful, but temperatures are still relatively mild at that time of year. Therefore, it is reasonable to prioritize shading over solar gain for the equinox cycles.
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Again, similar actions are taken which are previously noted, including a reduced overhang, incorporation of see-thru solar glazing and solar shading devices.
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EXISTING
REDESIGN
BAND OF SUN ANALYSIS WINTER SOLSTICE • AT SECT 7 The four foot overhang and lower roof block about half of the sun from the clerestory window, but the lower window receives a fair amount of solar gain and the light shelf is utilized in this scenario to bring the solar gain deeper into the space. Again, adjusting the overhang will better optimize this while respecting the summer shading devices. In addition, incorporating solar onto the shading device and glazing produces a fair amount of electricity because of the large number of winter days with sun in Las Vegas. Finally, changing the material of the interior room wall to stone will increase its thermal mass and storage capability. 14
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Calculate and Graph the Solar Heat Design Guideline EXISTING: Ratio of south glass area to solar heated floor area: • South glass area = 854sf • Solar heated floor area = 1,725sf 854sf / 1,720sf = .5 Centennial Hills Transit Center SSF Determinants: • y(south glass / floor area = m(SSF) + b (standard performance) .09 = (.09/.21).35 + b b = -.06 .5 = .43x + -.06 = 1.3 SSF !! (superior performance) .09 = (.09/.27).48 + b b = -.07 .5 = .33x + -.06 = 1.7 SSF !!
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EXISTING Relationship to Design Guidelines for Thermal Mass: The thermal mass required to carry a SSF of 90% or higher is more than triple which the existing design has. The thermal mass is vastly undersized for the current SSF
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Calculate and Graph the Solar Heat Design Guideline (cont.) REDESIGN Ratio of south glass area to solar heated floor area: • South glass area = 554sf x (.6*) = 332sf • Solar heated floor area = 1,720sf 332sf / 1,720sf = .19; Mass to glass ratio: 5.2 * Integrated ‘see-thru’ photolvotaic glazing panels intercept 40 percent of the solar gain on the southern glazing wall. Centennial Hills Transit Center SSF Determinants: • y(south glass / floor area = m(SSF) + b (standard performance) .09 = (.09/.21).35 + b b = -.06 .19 = .43x + -.06 = .58 SSF (superior performance) .09 = (.09/.27).48 + b b = -.07 .19 = .33x + -.07 = .79 SSF
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See-thru PV glazing. Courtesy SAPA Solar
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REDESIGN Relationship to Design Guidelines for Thermal Mass: The thermal mass required to carry a SSF of 60% is a 4.4 masonry to collector surface area ratio. The current design has a ratio of 5.2, which is adequate.
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Evaluation The band of sun analysis revealed that the existing shading and glazing design is adequate for shading the extensive southern glazing wall in the summer and allowing the solar rays to penetrate the space during the winter and to a lesser extent the fall and spring equinox. However, in order to fully capitalize on the great solar resource in Las Vegas and further enhance the design solar shading devices and see-thru solar photolvotaics are proposed. While the glazing wall is properly shaded throughout the year, its extensiveness means that a significant amount of mass is required to maximize the solar heating potential during the winter. The current mass only accounts for one third of the mass required, primarily because of the small footprint of the building and the vast southern glazing wall.The small building footprint limits the amount to which the mass area can be altered, and the floor mass currently totals inches. Increasing the mass beyond this will yield limited benefit, as the effectiveness of thermal storage in masses over seven inches is greatly reduced. Therefore, the reduction of glazing is more appropriate and achieved through the incorporation of see-thru solar glazing and a raised sill height.
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Phase 3 Detailed Winter Heat Loss Calculations, and BLC Calculate the Heat Loss, using Recommended format for seminar. • ROOF ASSEMBLY (UxA = 60.6 Btu/ F°) The roof structure is comprised of corrugated metal decking atop steel t-flange beams which are supported by tube steel girders. Continuous insulation for this structure sits atop the metal decking and therefore the Assembly U factor used for BLC calculations is .032 per MEEB E.6.
• OPAQUE WALLS (NON-SOUTH Note: No south opaque walls) (UxA = 62.4 Btu/ F°) A 10” concrete wall is the primary structural backup for all opaque walls in the transit center. At the east and west walls, four-inch of face stones are hung from the concrete on both the interior and exterior to create a solid stone mass appearance. The exterior cavity of this wall assembly contains two inches of continuous rigid insulation. The assembly U factor used here is pulled from COMcheck software, which was utilized during the design process for envelope energy code compliance purposes. U factor = .087
The north wall has two inches of continuous rigid insulation on the exterior of the concrete structural wall in addition to a 10 inch air gap between the concrete backup and an interior concrete block partition. This air gap is a chase for plumbing equipment. Metal furring and zinc cladding system are attached to the exterior. Because of the furring the wall system was treated as a steel-framed system with appropriate cavity and insulation ratings. U factor = .042
• WINDOWS (NON-SOUTH) (UxA = 201.5 Btu/ F°) An extensive curtain wall system is used on all sides of the building for visual connectivity between the interior and exterior. The glazing system is a double pane, low-e, tinted system with a metal frame and thermal break. This assembly has a U factor of .26 according to COMcheck.
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• DOORS (NON-SOUTH) (UxA = 18.7 Btu/ F°) A glazed curtain wall door on the east and one on the west complete the curtain wall system and again allow for transparency. The doors consist of 18sf of glazing (62%) and 11sf of aluminum frame (38%). The U factor for these doors is listed as .27: A single unglazed, uninsulated steel door on the northern facade allows access to the sprinkler room. The U factor for the commercial steel door is also .27.
• SLAB EDGE (UxA = 143.1 Btu/ F°) A 4” concrete slab on grade is un-insulated horizontally as well as vertically. According to MEEB, this results in a U factor of .73.
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• FRESH AIR HEAT LOSSES (1,047.8 Btu/ F°) The building is categorized as a transportation waiting space and therefore carries a high occupant load. Through a code analysis the occupancy load was determined to be 127 occupants.
Recommended format for Heat Loss Calculations:
[see MEEB 10th Ex. 8.1 Part B page 227] [MEEB 11h Ex. 8.1 Part B page 230] Calculate UAns , the hourly heat loss/F° of the entire building except the south wall and its windows. Component Roof
U-value 0.032 X
Area, ft2 1,894 ft2 =
All non-south opaque walls, east & west north
0.087 0.042
X X
577 ft2 = 291 ft2 =
50.2 12.2
0.26
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775 ft2 =
201.5
0.27 0.27
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48 ft2 = 21 ft2 =
13.0 5.7
F2 slab = .73 X perim 196 ft =
143.1
All non-south windows Doors north, east and west, east & west north Slab Edge
UxA 60.6
Fresh air heat losses See Table E.25 for required cfm/person; 127 people X 7.5 cfm/person = 952.5 total cfm ; then 952.5 total cfm X [1.1 Btu min/h ft3 F °] = 1047.8 Btu/ F° Total UAns =
Calculate Building Load Coefficient and Overall Heat Loss Total UA(non-south) = 1,534.1 Btu/ F° Total Square Footage = 1,900sf BLC = 1,534.1 Btu/ F° x 24hrs = 36,818.4 UA(non-south) x 24hrs = Overall Heat Loss Total SF 1,534.1 Btu/ F° x 24hrs 1,900sf
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19.3 BTU / DDF ft2
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The allowed maximum overall heat loss is 6.6 Btu/DDF ft2 for Las Vegas. Therefore REDESIGN is required. The UA(non-south) must be reduced by two thirds in order to meet the heat loss requirements for a passively heated building in Las Vegas. Strategies: • The largest contributor to the high BLC is the extremely high lung loss number. By utilizing a heat exchanger this can be reduced by 80% and take a drastic chunk out of the BLC. - Change in UA = -838.2 Btu/ F° • The second issue in the current design is heat loss through the extensive curtain wall. This can be reduced by retaining view windows on the east, west and north walls that maintain the connection to the exterior but minimize the overall thermal transfer. In a sensitive manner, this can also help strengthen the way the building addresses the southern facade by maintaining that glazing wall and giving the building more of a focus on the loading zones to the south. - Change in UA = -112.3 (subtracting glazing) + 18.2 (adding zinc wall assembly) = -94.1Btu/ F° • The final major area to address is the uninsulated slab. While this could be considered a lost opportunity due to the financial impacts of insulating a slab, it would greatly benefit the overall heat loss greatly. - Change in UA = -91.6 Btu/ F°
REDESIGN CALCULATIONS
Recommended format for Heat Loss Calculations:
[see MEEB 10th Ex. 8.1 Part B page 227] [MEEB 11h Ex. 8.1 Part B page 230] Calculate UAns , the hourly heat loss/F° of the entire building except the south wall and its windows. Component Roof
U-value 0.032 X
Area, ft2 1,894 ft2 =
All non-south opaque walls, Stone on concrete Zinc on furring
0.087 0.042
X X
577 ft2 = 723 ft2 =
50.2 30.4
0.26
X
343 ft2 =
89.2
0.27 0.27
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48 ft2 = 21 ft2 =
13.0 5.7
F2 slab = .36 X perim 196 ft =
51.5
All non-south windows Doors north, east and west, east & west north Slab Edge
UxA 60.6
Fresh air heat losses See Table E.25 for required cfm/person; 127 people X 7.5 cfm/person = 952.5 total cfm ; then 952.5 total cfm X [1.1 Btu min/h ft3 F °] = 1047.8 Btu/ F° 1047.8 Btu/ F° X .2(accounting for heat exchanger) = 209.6 Btu/ F° Total UAns =
510.2
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Calculate Building Load Coefficient and Overall Heat Loss - REDESIGN Total UA(non-south) = 510.2 Btu/ F째 Total Square Footage = 1,900sf BLC = 1,534.1 Btu/ F째 x 24hrs = 12,244.8 UA(non-south) x 24hrs = Overall Heat Loss Total SF 510.2 Btu/ F째 x 24hrs 1,900sf
=
6.44 BTU / DDF ft2 < 6.6 BTU / DDF ft2 - OK
WEST FACADE REDESIGN
EAST FACADE REDESIGN
NORTH FACADE REDESIGN Compare Design with Passive System Characteristics This design falls under the glass and mass approach to passive design that emphasizes direct gain as the main passive solar heating strategy. The design has a relatively small ration of mass to glazing area with more emphasis on the mass thickness. In an effort to stay connected to the outdoors throughout the night for safety reasons, night insulation is not used in the design of Centennial Hills Transit Center. For these reasons I feel it is most comparable to DG-B2 that has a significant mass thickness but not a great ration of mass to glazing area and no night insulation.
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Phase 4 Summer Heat Gain Calculations The hot climate of Las Vegas makes summer heat gain a significant issue that must be recognized and appropriately addressed in the design of Centennial Hills Transit Center. In addition to considering the stark climate, the use of the building as a transit center means large numbers of people occupy the building during peak use, resulting in additional heat gain. The following analysis assesses the impact these issues have on the summer heat gain of the building, and how the design of the structure responds to these. Calculate heat gain for the existing building, including the daylight factor PART A • INTERNAL GAIN FOR PEOPLE AND EQUIPMENT (13.3 Btu/h ft2) This 1,700 square foot building hosts several functions, the primary of which is a transit center. Secondary spaces include offices, rest rooms and storage. The occupancy load for the transit center as a whole is 127 occupants for 1,700 sf, which is relatively close to the 15sf per person associated with the assembly space function. While it seems appropriate to use Assembly as the function for the waiting areas (985 sf), the office and service areas are more accurately described by the Office, U.S. function (735 sf). Therefore, a weighted average of these functions is used.
PART B • INTERNAL GAIN FROM ELECTRIC LIGHTS (1.0 Btu/h ft2) The average daylight factor (DF) is calculated using the method described in MEEB Table 14.4 for sidelighting and top-lighting to determine the heat gain due to electric lighting. I calculated the DF independently for three distinct spaces, and again took the weighted average of the associate heat gains for each DF. • Primary transit center = 580 sf of glazing area, 985 sf of floor area: DF = 12% • Primary office = 317 sf of glazing area, 520 sf of floor area: DF = 12% • Enclosed service area = 4.5 sf of tubular skylight area, 215 sf of floor area: DF = .7% 23
PART C • GAINS THROUGH ENVELOPE (23.0 Btu/h ft2) The summer design DB temperature for Las Vegas is 103.7°F. Numbers from Table C were pulled from the 100°F column to determine heat gain through shaded windows, opaque walls and roofs. In the current design, only the southern windows have shading devices. This presents a serious issue for heat gain, as shown in the calculations and is an opportunity to easily reduce the building’s heat gain.
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TOTAL GAINS “OPEN” (cross, stack ventilation) BUILDING (37.3 Btu/h ft2) The total gains from part A, B and C come to a total of 37.3 Btu/h ft2. Two major contributors to this number are the internal gain from people and equipment due to the building’s high intensity function as a transit center, and the unshaded windows to the north, east and west. The first issue is difficult to address without changing the function of the building, but the heat gain from unshaded windows presents a inexpensive and simple opportunity to reduce the total gains. PART E • HEAT GAINS FROM FORCED VENTILATION (1.6 Btu/h ft2) This calculation again required a weighted average of the transit center portion of the program and the offices. The square footage of the transit center is multiplied by the recommended constant in MEEB as is the area of the office. The total cfm is reached by adding these two together.
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This total is then divided by the total floor area and multiplied by the ventilation constant for closed buildings with an outdoor temperature of 100°F. It should be noted again that Las Vegas has a summer design DB temperature of 103.7°F, but the 100°F number should suffice for these preliminary calculation purposes. TOTAL HEAT GAINS “CLOSED” (roof ponds, evaporative cooling, daytime or “closed” hours of thermal mass/night ventilation) BUILDING (39.9 Btu/h ft2) The total gains for the “open” building is taken here and added to the forced ventilation gains from Part E. No assumptions were made here, pure calculations. • FULL CALCULATIONS ON THE FOLLOWING PAGE
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Recommended format for Heat Gain Calculations:
[see MEEB 10th Ex. 8.1 Part D page 236, and Table F.3, pages 1610, 1611] [see MEEB 11th Ex. 8.1 Part D page 240, and Table F.3, pages 1650, 1651] Part A: Internal gain from people and equipment: Function is Assembly for which total people + equipment gain is 21 Btu/h ft2 Function is Office U.S. for which total people + equipment gain is 3 Btu/h ft2 [(21 Btu/h ft2 x 985sf) + (3 Btu/h ft2 x 735sf)] / 1,720sf = 13.3 Btu/h ft2 Part B: Internal gain from electric lights: first calculate DFav Table 14.4, page 595 [603] (1) Transit Center Sidelight DFav = 0.2 [(580/985] = 0.12 (12%) Total DFav = 0.12 (12%) Electric lighting heat gain, based on DFav = .4 Btu/h ft2 (2) Primary Office Sidelight DFav = 0.2 [(317/520] = 0.12 (12%) Total DFav = 0.12 (12%) Electric lighting heat gain, based on DFav = .5 Btu/h ft2 (3) Enclosed office/restroom/service Toplight DFav = 0.35 [4.5/215] = 0.007 (.7%) See Table 14.4 for 0.X, depending on skylight type Total DFav = 0.007 (.7%) Electric lighting heat gain, based on DFav = 5.1 Btu/h ft2 [(.4 Btu/h ft2 x 985sf) + (.5 Btu/h ft2 x 520sf)] + (5.1 Btu/h ft2 x 215sf)]/ 1,720sf Total Electric lighting heat gain, based on DFav = 1 Btu/h ft2 Part C: Gains Through Envelope: Summer design DB temperature [Table B.1] = 103.7°F Windows: if unshaded externally, use multipliers from Table F.6 Part B, page 1616 [1656] (Shaded) South glass 554 ft2 X 21 multiplier Btu/h ft2 = 6.6 Btu/h ft2 Total floor area 1,720 ft2 (Unshaded) North glass 115 ft2 X ~27 multiplier Btu/h ft2 = 1.8 Btu/h ft2 Total floor area 1,720 ft2 (Unshaded) East glass 130 ft2 X ~76 multiplier Btu/h ft2 = 5.7 Btu/h ft2 Total floor area 1,720 ft2 (Unshaded) West glass 98 ft2 Total floor area 1,720 ft2
X ~76 multiplier Btu/h ft2 = 4.3 Btu/h ft2
Walls: Concrete wall area 577 ft2 Total floor area 620 ft2 X U= 0.087 X 25 multiplier Btu/h ft2 = 2 Btu/h ft2 Zinc wall area 1,023 ft2 Total floor area 1,100 ft2 X U= 0.042 X 25 multiplier Btu/h ft2 =1 Btu/h ft2 Roof: Total roof area 1,894 ft2 Total floor area 1,720 ft2 X U= 0.032 x 45 multiplier Btu/h ft2 =1.6 Btu/h ft2
•Opportunity for redesign to address high heat gain number add exterior shading devices to east and west facades. See-thru PV louvers provide shading, allow occupants to maintain a visual connection, speak to the aesthetic quality of the south facade and produce energy.
Total Gains, “Open” [cross, stack] Building: 13.3 + 1 +23= 37.3 Btu/h ft2 Part E: Heat Gains from Forced Ventilation [building is above outdoor temp.] See Table E.25 page 1597+ [p. 1638+] for required cfm/ ft2 of outdoor air; 985 ft2 X .06 cfm/ ft2 = 59.1 cfm 735 ft2 X .06 cfm/ ft2 = 44.1 cfm 59.1 cfm + 44.1 cfm = 103.2 total cfm Total cfm 103.2 ft3 Total floor area 1,720 ft2 X 27 multiplier Btu/h ft2 = 1.6 Btu/h ft2
Total Heat Gains, “Closed”Building: 13.3 + 1 +23 + 1.6 = 38.9 Btu/h ft2
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Strategies: •Control the east and west heat gain through the windows by placing exterior louvers or fins. • A significant source of heat gain is the large southern glazing wall. During previous exercises exploring heat loss this glazing was significantly reduced to the quantity used in this calculation. In order to maintain the strong visual connection to the loading zone to the south I decided not to reduce this any further. Instead, I aim address the extra heat gain resulting from these windows through passive cooling techniques. Recommended format for Heat Gain Calculations:
[see MEEB 10th Ex. 8.1 Part D page 236, and Table F.3, pages 1610, 1611] [see MEEB 11th Ex. 8.1 Part D page 240, and Table F.3, pages 1650, 1651] Part A: Internal gain from people and equipment: Function is Assembly for which total people + equipment gain is 21 Btu/h ft2 Function is Office U.S. for which total people + equipment gain is 3 Btu/h ft2 [(21 Btu/h ft2 x 985sf) + (3 Btu/h ft2 x 735sf)] / 1,720sf = 13.3 Btu/h ft2 Part B: Internal gain from electric lights: first calculate DFav Table 14.4, page 595 [603] (1) Transit Center Sidelight DFav = 0.2 [(580/985] = 0.12 (12%) Total DFav = 0.12 (12%) Electric lighting heat gain, based on DFav = .4 Btu/h ft2 (2) Primary Office Sidelight DFav = 0.2 [(317/520] = 0.12 (12%) Total DFav = 0.12 (12%) Electric lighting heat gain, based on DFav = .5 Btu/h ft2 (3) Enclosed office/restroom/service Toplight DFav = 0.35 [4.5/215] = 0.007 (.7%) See Table 14.4 for 0.X, depending on skylight type Total DFav = 0.007 (.7%) Electric lighting heat gain, based on DFav = 5.1 Btu/h ft2 [(.4 Btu/h ft2 x 985sf) + (.5 Btu/h ft2 x 520sf)] + (5.1 Btu/h ft2 x 215sf)]/ 1,720sf Total Electric lighting heat gain, based on DFav = 1 Btu/h ft2 Part C: Gains Through Envelope: Summer design DB temperature [Table B.1] = 103.7°F Windows: if unshaded externally, use multipliers from Table F.6 Part B, page 1616 [1656] (Shaded) South glass 554 ft2 X 21 multiplier Btu/h ft2 = 6.6 Btu/h ft2 Total floor area 1,720 ft2 (1/2 drawn roller shades) North glass 115 ft2 Total floor area 1,720 ft2 X ~27 multiplier Btu/h ft2 = 1.8 Btu/h ft2 (Shaded) East glass 130 ft2 Total floor area 1,720 ft2
X 21 multiplier Btu/h ft2 = 1.6 Btu/h ft2
(Shaded) West glass 98 ft2 Total floor area 1,720 ft2
X 21 multiplier Btu/h ft2 = 1.2 Btu/h ft2
Walls: Concrete wall area 577 ft2 Total floor area 620 ft2 X U= 0.087 X 25 multiplier Btu/h ft2 = 2 Btu/h ft2 Zinc wall area 1,023 ft2 Total floor area 1,100 ft2 X U= 0.042 X 25 multiplier Btu/h ft2 =1 Btu/h ft2 Roof: Total roof area 1,894 ft2 Total floor area 1,720 ft2 X U= 0.032 x 45 multiplier Btu/h ft2 =1.6 Btu/h ft2
Total Gains, “Open” [cross, stack] Building: 13.3 + 1 +15.8= 30.1 Btu/h ft2 Part E: Heat Gains from Forced Ventilation [building is above outdoor temp.] See Table E.25 page 1597+ [p. 1638+] for required cfm/ ft2 of outdoor air; 985 ft2 X .06 cfm/ ft2 = 59.1 cfm 735 ft2 X .06 cfm/ ft2 = 44.1 cfm 118.2 cfm + 44.1 cfm = 103.2 total cfm Total cfm 162.3 ft3 Total floor area 1,720 ft2 X 27 multiplier Btu/h ft2 = 1.6 Btu/h ft2
Total Heat Gains “Closed” Bldg: 13.3 + 1 +15.8 + 1.6 = 31.7 Btu/h ft2
28
Total heat gain calculations in preferred formats: • CROSS AND STACK VENTILATION (FLOOR AREA) = 30.1 Btu/h ft2 Part A + B + C = 13.3 + 1 + 15.8 = 30.1 Btu/h ft2 • VENTILATION OF MASS (FLOOR AREA) = 760 Btu/day ft2 Part A + B + C + E = 13.3 + 1 + 15.8 + 1.6 = 31.7 Btu/h ft2 X 24hr/day = 760.8 Btu/day ft2 • COOLTOWERS (FLOOR AREA) = 54,523 Btu/h Part A + B + C + E = 13.3 + 1 + 15.8 + 1.6 = 31.7 Btu/h ft2 X 1720ft2 = 54,523 Btu/h Hours above the comfort zone: Approximately 18-20 hours of the day on the design chart fall outside of the comfort zone.
29
SOUTH BEND, IN 54 11.9 11.2 11.9 11.6 10.2 9.1 8.1 7.7 8.5 9.5 DES MOINES, IA 53 11.4 11.2 12.4 12.6 11.0 10.1 8.9 8.6 9.4 10.3 SIOUX CITY, IA 61 11.4 11.2 12.3 13.2 11.8 10.7 9.2 9.1 9.9 10.5 WATERLOO, IA 46 11.4 11.4 12.1 12.6 11.1 9.8 8.4 8.3 9.0 10.2 CONCORDIA, KS 40 11.7 12.1 13.4 13.8 12.1 11.7 11.3 10.9 11.2 11.6 DODGE CITY, KS 60 13.5 13.9 15.5 15.5 14.6 14.0 13.1 12.5 13.5 13.5 GOODLAND, KS 54 12.4 12.4 14.0 14.4 13.5 12.7 11.9 11.5 12.0 11.9 TOPEKA, KS 53 9.7 10.2 11.5 11.7 10.2 9.4 8.4 8.0 8.5 9.0 WICHITA, KS 49 12.0 12.5 13.8 14.0 12.3 12.2 11.3 11.1 11.6 11.9 GREATER CINCINNATI AP 55 10.4 10.4 11.0 10.6 8.7 7.9 7.2 6.8 7.4 8.1 JACKSON, KY 21 7.3 7.4 7.6 7.7 6.0 5.3 5.0 4.6 5.3 6.0 LEXINGTON, KY 55 10.6 10.6 10.9 10.4 8.6 7.9 7.2 6.8 7.6 8.1 LOUISVILLE, KY 55 9.5 9.5 10.1 9.7 8.0 7.4 6.8 6.4 6.8 7.2 PADUCAH KY 18 8.8 8.9 9.4 8.9 7.4 6.2 5.7 5.1 5.6 6.5 BATON ROUGE, LA 51 8.7 9.1 9.1 8.7 7.6 6.5 5.9 5.6 6.4 6.6 LAKE CHARLES, LA 41 9.8 10.0 10.2 9.8 8.6 7.5 6.1 6.1 7.1 7.8 NEW ORLEANS, LA 54 9.3 9.8 9.9 9.4 8.1 6.8 6.1 5.9 7.3 7.6 SHREVEPORT, LA 50 9.2 9.6 10.0 9.6 8.3 7.6 7.1 6.6 7.2 7.4 CARIBOU, ME 22 11.1 10.8 11.7 10.9 10.3 9.3 8.6 8.1 9.2 10.0 PORTLAND, ME 62 9.0 9.4 10.0 9.9 9.1 8.2 7.6 7.5 7.8 8.4 BALTIMORE, MD 52 9.4 9.9 10.7 10.2 8.9 8.2 7.6 7.5 7.7 8.1 61 Normal 17.2 Daily 17.2Maximum 17.2 Temperature, 16.4 14.6 12.9 12.6 13.5 15.2 11/1/11BLUE HILL, MA Deg F 13.8 BOSTON, MA 45 13.7 13.7 13.6 13.1 12.0 11.4 11.0 10.8 11.3 11.9 SAVANNAH, 30 60.4 64.1 71.0 77.7 84.3 89.5 92.3 90.3 86.0 78.1 WORCESTER,GA MA 36 11.7 11.6 11.5 11.0 10.0 8.9 8.4 8.3 8.6 9.4 HILO, HIMI 30 79.2 79.4 79.2 79.3 80.6 82.2 82.5 83.2 83.4 82.7 ALPENA, 42 8.8 8.4 8.9 9.2 8.3 7.5 7.0 6.7 7.1 7.8 HONOLULU,HI 30 80.4 80.7 81.7 83.1 84.9 86.9 87.8 88.9 88.9 87.2 DETROIT, MI 44 11.9 11.4 11.7 11.3 10.1 9.2 8.5 8.1 8.7 9.7 KAHULUI, 30 80.3 80.8 81.5 82.5 84.3 86.0 86.9 87.9 88.1 86.9 FLINT, MIHI 61 11.8 11.2 11.8 11.5 10.1 9.0 8.1 7.8 8.8 9.8 LIHUE, HI 30 77.9 77.9 78.1 78.8 80.6 82.7 83.9 84.9 85.0 83.5 GRAND RAPIDS, MI 39 11.4 10.6 11.1 11.0 9.7 8.9 8.3 7.9 8.3 9.4 11/1/11BOISE, ID www.wrcc.dri.edu/htmlfiles/westwinddir.html 30 36.7 44.5 53.6 61.7 70.7 80.3 89.2 88.0 77.2 64.3 HOUGHTON LAKE, MI 21 9.7 9.1 9.1 9.5 8.8 7.8 7.5 7.0 7.8 8.8 LEWISTON, ID 78.0 87.6 SALMON MI AIRPORT, ID (KSMN). 30 N 70.0 N N N8.0 87.6 N7.5 N76.7 LANSING, 43 | 39.4 11.7 N 45.6 10.9 N 53.8 11.2N 61.6 11.1 9.9 8.8 8.2 N 62.0 9.4 N POCATELLO, ID 30 78.3 87.5 MUSKEGON, 41 | 32.5 12.2 11.6 11.6 11.5 9.9 9.3 9.3 S 62.0 10.7 S STANLEY MI RNGR STN, ID (KSNT). SSE 39.0 SSE 48.5 SSE 58.5 N 67.7 S S S8.8 86.8 S8.6 S75.7 CHICAGO,IL 30 29.6 34.7 46.1 58.0 69.9 79.2 83.5 81.2 73.9 62.1 SAULT STE. MARIE, MI 9.6 9.3 9.7 8.5 7.8 7.7 8.6 9.2 TWIN FALLS AP, ID (KTWF). 61 W |29.8 SSW 35.6 W 10.0 W 10.3 W 73.3 W W SSW SSW SSW76.5 SSW 64.4 SSW MOLINE, 30 48.3 61.7 82.7 86.1 83.9 DULUTH, IL MN 53 11.6 11.3 11.8 12.3 11.6 10.4 9.4 9.4 10.3 11.2 PEORIA, IL 30 30.7 36.6 49.4 62.0 73.0 82.2 85.7 83.6 76.7 64.4 INTERNATIONAL FALLS, MN 50 8.9 8.8 9.4 9.9 9.4 8.5 7.7 7.5 8.5 9.3 ROCKFORD, IL 30 27.2 33.0 45.5 59.1 71.2 79.9 83.1 80.9 73.9 61.8 MINNEAPOLIS-ST.PAUL, MN 64 10.5 10.4 11.3 12.2 11.1 10.4 9.4 9.2 10.0 10.6 SPRINGFIELD, 30 33.1 38.9 51.1 63.4 74.4 83.3 86.5 84.5 78.5 66.6 ROCHESTER, MNIL 42 14.2 13.7 14.1 14.3 MONTANA 13.2 12.1 10.8 10.4 11.5 12.7 EVANSVILLE, 30 39.5 45.4 56.4 67.2 77.1 86.1 89.4 87.8 81.3 70.0 SAINT CLOUD,IN MN 16 8.4 8.4 9.0 9.8 9.2 8.3 7.1 6.5 7.2 8.4 FORT WAYNE, 30 31.0 35.4 47.4 59.8 71.6 80.6 84.3 81.8 75.4 63.0 JACKSON, MS IN 39 8.2 8.4 8.7 8.0 6.8 6.1 5.2 5.3 6.1 6.2 PREVAILING WIND82.1 DIRECTION INDIANAPOLIS, 30 34.5 39.9 51.4 62.9 73.5 85.6 83.7 77.4 65.6 MERIDIAN, MS IN 43 7.1 7.5 7.9 7.1 6.0 5.2 4.9 4.6 5.3 5.2 SOUTH BEND, 30 31.0 35.5 46.8 58.9 70.7 79.6 83.1 80.7 73.6 61.8 TUPELO, MS IN 19 7.6 8.2 8.3 7.8 6.6 5.7 5.3 5.2 6.1 6.0 DES MOINES, IA 30 29.1 35.4 48.2 61.3 72.3 81.8 86.0 83.9 75.9 63.5 COLUMBIA, MO 32 10.7 10.8 11.7 11.5 9.1 8.7 8.2 7.9 8.6 STATION | JAN FEB MAR APR MAY JUN JUL AUG SEP OCT 9.3 NOV DUBUQUE,IA 30 24.8 30.8 43.3 57.4 69.3 78.6 82.1 79.8 71.9 60.3 KANSAS CITY, MO 30 11.1 11.1 12.3 12.3 10.3 9.9 9.2 8.8 9.6 10.5 SIOUX CITY,MO IA 30 28.7 35.0 47.3 61.7 73.2 82.5 86.2 83.7 76.0 63.7 ST. LOUIS, 53 10.6 10.8 11.6 11.3 9.4 8.8 8.0 7.6 8.2 8.9 BAKER MUNI AP, MT (KBHK). 30 SE 59.7 SE 72.2 W W SE WATERLOO, IA MO 81.7 85.0 82.8 SPRINGFIELD, 57W | 25.8 11.4 W 31.9 11.5 W 45.0 12.5 12.0 10.2 9.3 8.4 SE 8.4ESE75.3 9.1 W 62.5 10.1 W CONCORDIA, 30 90.7 88.4 BILLINGS, 63 | 36.3 13.0SW 42.9 12.3 11.4 11.4 10.7 10.1 9.5 SW79.9 10.2 SW 67.9 11.0SW BILLINGSMTKS AP, MT (KBIL). WIN SW 53.9 SW 64.4 SW 74.0 N N9.5 SW 2N 85.0 DODGE CITY, KS 30 41.4 48.3 57.3 67.1 75.9 86.9 92.8 90.8 82.0 GLASGOW, MT 33 9.8 10.1 11.2 12.3 12.2 11.1 10.5 10.9 10.9 10.6 BOZEMAN-BELGRADE AP, MT (KBZ |39.4 S 45.0 SSE SSE 62.7 W 71.7 SE W SSE SSE SE78.0 SE 70.4 SSE KS MT 30 83.6 89.1 86.7 66.0 11/1/11GOODLAND, Wind-13.9 Average53.2 Wind SpeedGREAT FALLS, 61 14.9 12.8 12.6 (MPH) 11.3 11.1 10.0 10.1 11.2 12.9 BUTTE AP, MT (KBTM). WIND R | S S S N N N N S S S S TOPEKA, KS 30 37.2 43.8 55.5 66.1 75.3 84.5 89.1 87.9 80.3 68.9 HAVRE, MT 3 8.8 9.4 10.2 11.6 12.4 10.8 9.8 9.0 9.4 9.1 CUT BANK AP, MT (KCTB). WIN | WSW WSW WSW W W W W W W WSW WSW WICHITA, KS 30 40.1 47.2 57.3 66.9 76.0 87.1 92.9 91.6 82.2 70.2 HELENA, MT 62 6.7 7.3 8.2 9.1 8.8 8.5 7.8 7.4 7.4 7.1 NCDC / Get/View Data / Comparative Climatic Data / Search GREATER AP 30 82.4 86.4 KALISPELL, MT MT (KDLN). 40 | 38.0 5.6 S 43.1 5.6 S 53.9 6.7S 64.7 7.7 7.4 6.9 6.1 S 66.4 5.1 S DILLON CINCINNATI AP, WIND S 74.4 S S S6.3 84.8 S6.3 S78.0 JACKSON, 30 80.8 84.2 MISSOULA, 58 | 42.0 5.1 5.6 6.7E 66.8 7.6 7.4 7.2 6.0 5.1 E GLASGOWKYMT AIRPORT, MT (KGGW). ESE 46.8 ESE 56.8 E 73.8 E E E6.9 83.3 E6.7 E77.4 ESE 67.5 LEXINGTON, KY NE 30 39.9 45.2 55.3 65.1 74.0 82.3 85.9 84.6 78.1 66.9 GRAND ISLAND, 53 11.7 11.7 13.1 14.0 12.6 11.8 10.5 10.3 11.0 11.2 GLENDIVE AIRPORT, MT (KGDV). |41.0 S 46.6 S 56.8 S 66.8 NW 75.4 NW W NW S9.1 NW79.4 S 68.4 S LOUISVILLE, 30 83.3 87.0 85.8 LINCOLN, NE KY 30 9.6 10.0 11.3 12.1 10.5 9.8 9.3 9.5 9.9 PADUCAH KY 85.2 88.6 87.4 GREAT FALLS AP, MT (KGTF). 30 SW 58.1 SW 68.4 SW 76.9 SW SW SW NORFOLK, NE 26 | 41.9 11.6SW 48.0 11.5 12.5 13.1 11.5 10.8 9.7 SW 9.5 SW81.2 10.3 SW 70.8 11.0SW BATON LA 30 89.2 90.7 NORTH PLATTE, NE 50 | 60.0 9.2SW 63.9 9.8 11.5 12.6 11.5 10.4 9.7 SW 79.7 9.6SW GREATROUGE, FALLS-MALSTROM AFB, MT SW 71.0 SW 77.3 SW 84.0 SW W W9.5 90.9 W9.2 SW87.4 LAKE CHARLES, LA NE 30 88.9 91.0 91.3 87.7 OMAHA EPPLEY AP, 66W | 60.6 10.9SW 64.5 11.1 12.2 12.6 10.9 10.1 9.4 SW 80.5 9.8SW HAVRE AIRPORT, MT (KHVR). YRS SW 71.3 SW 77.4 E 84.1 E E E8.8 E8.8 DATA THROUGH 2002 JAN FEB MAR APR MAY JUN JUL AUG SW87.1 SEP OCT NEW ORLEANS, LANE 30 61.8 65.3 72.1 78.0 84.8 89.4 91.1 91.0 79.7 OMAHA (NORTH), 9 9.9 9.2 10.5 10.2 8.9 8.3 7.5 7.6 8.6 9.0 BIRMINGHAM AP,AL 59 | 56.2 8.1 W 62.0 8.7 W 69.7 9.0W 76.6 8.2 6.8 6.0 5.7 5.4 W87.6 6.3 W 78.3 6.2 W HELENA AIRPORT, MT (KHLN). W W W W W SHREVEPORT, LA 30 83.2 89.8 93.3 93.4 SCOTTSBLUFF, NE 51 10.6 11.1 12.0 12.5 11.8 10.5 9.3 8.9 9.4 9.7 HUNTSVILLE, AL 35 9.0 9.4 9.8 9.2 7.9 6.9 6.0 5.8 6.7 7.3 W CARIBOU, 71.8 76.3 JORDAN ME AIRPORT, MT (KJDN). 30 W 62.6 W W W9.1 74.2 W9.2 W64.1 VALENTINE, NE 34 | 19.3 9.3 W 23.2 9.4 W 34.1 10.4W 47.0 11.1 11.0 9.9 9.7 W 51.4 9.5 MOBILE, ALME 54 10.1 10.3 10.7 10.1 8.7 7.5 6.9 6.7 7.7 8.0 PORTLAND, 30 30.9 34.1 42.2 52.8 63.3 72.8 78.8 77.3 68.9 57.9 ELKO, NV 47 | 5.2 S 5.7 S 6.6 7.2 6.8 SSE 6.7 SSE 6.2 5.9 S 5.4 S 5.0 S KALISPELL AP, MT (KFCA). WI SSE SSE SSE S5.2 MONTGOMERY, AL 58 7.7 8.2 8.3 7.3 6.1 5.8 5.7 5.9 5.7 BALTIMORE, MD 30 41.2 44.8 53.9 64.5 73.9 82.7 87.2 85.1 78.2 67.0 ELY, NV 61 10.1 10.3 10.7 10.9 10.7 10.6 10.3 10.4 10.3 10.0 LEWISTOWN WNW E ESE ANCHORAGE, AKAIRPORT, MT (KLWT) 49 | 33.8 6.4SW 36.3 6.8 W 44.8 7.1W 55.5 7.3 8.5 8.4 ESE 7.3 ESE 6.9ESE71.0 6.7 W 60.3 6.7SW BLUE HILL, MA 30 67.0 75.5 81.2 78.9 LAS VEGAS, NV 54 7.4 8.5 10.1 11.0 11.0 11.0 10.2 9.6 9.0 8.1 ANNETTE, AK 38 11.6 11.8 10.5 10.6 9.0 8.5 7.7 8.1 8.8 11.2 LIVINGSTON AP, MT (KLVM). 30 WSW 38.7 WSW 46.3 W 66.7 W W W7.2 80.1 W6.6 W72.5 WSW BOSTON, 76.6 82.2 RENO, NVMA 60W | 36.5 5.6 6.2 7.8W 56.1 8.2 8.0 7.7 5.8 W 61.8 5.4 BARROW, AK 69 11.9 11.3 11.3 11.5 12.0 11.5 11.7 12.4 13.2 13.3 WORCESTER, MA 74.4 79.3 77.1 MILES CITY NW 54.4 NW 66.3 NW NW NW WINNEMUCCA, NV AP, MT (KMLS). 30 46W | 31.4 7.6 S 34.1 8.0 S 43.0 8.6 8.6 8.6 8.5 8.4 SSE 7.8 NW69.0 7.6 S 58.4 7.3 S BARTER IS.,AK 33 15.1 14.4 13.7 12.0 12.7 11.6 10.9 11.8 13.2 14.8 ALPENA, MI 30 26.1 28.2 37.3 50.3 64.3 73.8 79.0 76.1 67.4 55.6 CONCORD, NH 60 7.2 7.9 8.1 7.8 7.0 6.5 5.7 5.4 5.6 6.0 MISSOULA AIRPORT, MT (KMSO). ESE 14.7 ESE 13.7N 12.9 NW 11.5 N NW N N N11.6 W 12.3 ESE BETHEL, AK 44 | 14.5 11.0 10.6 11.0 DETROIT, MI 34.4 45.2 70.2 79.0 83.4 81.4 73.7 61.2 MT. WASHINGTON, NH MT (KSDY). 30 67 | 31.1 46.1 41.4S 57.8 35.8 27.3 25.3 33.8 SIDNEY MUNI AP, SSW 44.3 N 29.7 S S S6.5 24.7 S6.2 S28.8 SSW BETTLES,AK 27 5.8 6.3 S 43.1 7.0 7.4 7.2 6.8 6.4 S 59.7 6.4 FLINT, MICITY 30 29.2 32.3 56.2 69.0 77.7 82.0 79.5 71.9 ATLANTIC AP, NJ 44 10.7 11.1 11.8 11.4 10.1 9.1 8.3 7.9 8.3 8.7 BIG DELTA,AK 26 11.2 10.2 8.8 8.0 8.2 6.9 6.1 6.6 7.6 8.7 WOLF POINT AP, MT (KOLF). W | W W ENE E W W E E E W GRAND RAPIDS, MI 30 29.3 32.6 43.3 56.6 69.6 78.4 82.3 79.7 71.7 59.6 NEWARK, NJ 58 11.2 11.5 11.9 11.2 10.0 9.5 8.9 8.7 9.0 9.4 W COLD BAY,AK 47 17.5 17.9 17.4 17.5 16.2 15.8 15.6 16.2 16.2 16.6 HOUGHTON LAKE, 30 25.9 29.3 39.4 53.0 67.2 75.5 80.0 77.1 68.3 56.0 ALBUQUERQUE, NMMI 63 8.0 8.8 9.9 10.7 10.5 9.8 8.9 8.1 8.4 8.2 FAIRBANKS, AK 51 3.0 3.9 5.3 6.6 7.7 7.1 6.6 6.1 6.0 5.3 LANSING, 30 29.4 32.6 43.5 56.6 69.4 78.1 82.1 79.7 72.0 59.8 CLAYTON, MI NM 10 11.9 12.4 13.1 14.4 13.2 12.9 11.2 10.2 11.3 11.8 GULKANA,AK MI 14 5.0 4.9 6.3 8.5 8.7 8.1 7.7 7.7 7.3 6.0 MARQUETTE, 30 19.7 24.2 33.1 45.8 61.5 70.3 75.2 72.6 63.2 50.9 ROSWELL, NM 29 7.7 8.6 10.1 10.2 NEVADA 9.9 9.7 8.6 7.9 8.0 7.9 HOMER, AK 28 7.8 7.7 7.8 8.1 8.2 7.8 7.1 6.6 7.0 7.3 MUSKEGON, 30 29.8 32.5 42.5 54.6 67.0 75.6 80.0 78.1 70.3 58.7 ALBANY, NYMI 64 9.8 10.1 10.6 10.5 9.0 8.3 7.5 7.0 7.4 8.0 JUNEAU, AK MARIE, MI 57 8.1 8.2 8.4 8.5 8.3 7.7 7.5 7.4 8.0 9.5 SAULT STE. 30 21.5 24.5 33.6 48.0 63.2 70.7 75.7 74.1 64.8 52.8 KING SALMON, AK 47 10.5 11.0 11.3 10.9 11.0 10.5 9.9 10.0 10.4 10.3 DULUTH, MN 30 17.9 24.4 34.2 49.0 63.4 71.2 76.3 73.9 64.5 52.5 PREVAILING WIND DIRECTION KODIAK, AK 49 12.7 12.5 12.5 11.6 10.6 9.3 7.7 8.4 9.7 11.4 INTERNATIONAL FALLS, MN 30 13.8 22.4 34.9 51.5 66.6 74.2 78.6 76.3 64.7 51.7 KOTZEBUE, AK 56 13.9 13.0 11.9 12.0 10.7 11.9 12.7 13.2 13.2 13.5 MINNEAPOLIS-ST.PAUL, MN 30 21.9 28.4 40.6 57.0 70.1 79.0 83.3 80.4 71.1 58.4 STATION JAN 26.2 FEB 38.7 MAR 54.8 APR MAY OCT 56.9 NOV MCGRATH, AKMN 52 3.2 4.2 5.3 6.5 6.7 JUN 6.4 JUL 5.9 AUG 5.8SEP69.2 5.9 5.4 lwf.ncdc.noaa.gov/oa/climate/online/ccd/avgwind.html ROCHESTER, 30 | 19.9 67.7 76.6 80.1 77.5 NOME, CLOUD, AK 55 10.8 11.0 10.1 10.1 9.9 9.7 9.7 10.4 11.0 10.5 SAINT MN 30 18.7 25.7 37.7 54.9 69.0 77.3 81.7 78.9 69.0 56.3 ST. PAUL ISLAND, AK 28 19.9 20.0 18.8 17.4 14.9 13.6 12.1 13.7 15.4 17.4 JACKSON, MS AP, NV (KP38). 30 | 55.1 88.9 91.4 CALIENTE WIN NNE 60.3 S 68.1 S 75.0 S 82.1 S S S4.2 91.4 S3.7 S86.4 S 76.8 NNE TALKEETNA,MS AK 19 6.0 5.5 5.5 4.7 4.9 5.1 3.7 3.8 MERIDIAN, 30 83.9 90.1 92.9 92.9 88.0 DESERT ROCK-MERCURY, NV (KDR |57.5 NNE 62.6 NNE 70.3 NNE 77.1 NNE SW SW SW NNE 78.3 NNE VALDEZ, 22 7.5 7.8 6.7 5.2 5.8 5.9 4.9 SSW 4.2SSW84.9 4.3 6.3 TUPELO, AK MS 30 50.3 56.0 64.8 73.5 81.0 88.0 91.4 90.9 74.9 YAKUTAT, AK 54 | 37.4 7.2 E 43.9 7.3 E 55.1 7.0W 65.9 7.1 7.5 6.9 6.9 W 68.0 7.8 E ELKO AIRPORT, NV (KEKO). WI W 74.6 W W W6.6 87.3 W6.3 W79.1 COLUMBIA, MO 30 83.6 88.6 FLAGSTAFF, AZ 35 6.5 6.6 7.1 7.6 7.3 7.0 5.5 5.0 5.6 5.8 ELY AIRPORT, WIN S 74.6 S S S S S79.0 S 67.6 S KANSAS CITY, MO NV (KELY). 30 | 36.0 S 42.6 S 54.4S 65.2 83.9 88.8 87.1 PHOENIX, AZMO 57 5.3 5.8 6.6 6.9 7.0 6.7 6.3 5.8 ST. LOUIS, 85.3 89.8 87.9 EUREKA AIRPORT, NV (KP68). 30 |37.9 SSE 44.3 SSE 55.4 S 66.7 S 76.5 S S S7.1 S6.6 S80.1 S 68.3 S TUCSON, AZ 57 7.9 8.1 8.6 8.9 8.8 8.7 8.4 7.9 8.3 8.2 SPRINGFIELD, MO 30 41.6 47.7 57.8 67.7 75.9 84.6 89.9 89.5 70.6 FALLON AZ NAS, NV (KNFL). WIND N 10.7 W N W9.0 WNW8.4 N81.2 WINSLOW, 42 | 32.8 7.1 S 39.5 8.5 S 47.6 10.3S 57.5 11.3 10.6 8.1 N 58.9 7.6 S BILLINGS, MT 30 67.4 78.0 85.8 84.5 71.8 YUMA, AZ 28 7.3 7.4 7.9 8.3 8.3 8.5 9.5 8.9 7.3 6.6 LAS VEGAS AIRPORT, NV (KLAS) | W W W SW SW S S S S W GLASGOW, MT 30 19.9 28.3 41.3 56.7 67.9 77.1 83.8 83.3 70.4 57.1 W FORT 57 | 32.1 8.2NE 37.7 8.5 9.4S 55.6 8.9 7.7 6.7 6.6 6.8 LAS SMITH, VEGAS-NELLIS AFB, NV (KL NE 45.3 S 64.7 S S S6.3 81.2 S6.3 S69.6 NNE 58.0 NNE GREAT FALLS,AR MT 30 73.9 82.0 LITTLE ROCK, AR 60 8.4 8.9 9.6 9.0 7.6 7.1 6.7 6.3 6.6 6.8 MT 30 |Normal 25.5 33.4 44.9 58.5 84.6 11/1/11HAVRE, Maximum Deg LOVELOCK AIRPORT, NV (KLOL). NNEDaily NNE NNETemperature, N 68.8 W F 77.4 W S7.2 83.9 S6.8 NE71.9 NNE 59.4 E BAKERSFIELD, CA 50 5.2 5.8 6.5 7.1 7.9 7.9 6.2 5.5 HELENA, MT 30 30.5 37.3 65.9 75.0 83.4 58.4 NORTH LASMTVEGAS AP, NV (KVGT NW 46.8 NNW 56.9 SSW S S S5.8 82.5 S5.9 NW71.0 NNW BLUE CANYON, CA 50 | 28.9 7.8NW 35.2 7.7 7.4 6.5 6.5 6.3 6.4 NW 55.3 6.8 KALISPELL, 30 44.9 56.0 64.7 71.9 80.2 80.5 69.0 NCDC Get/View Data Comparative / Search EUREKA, CA. 6.9 S /37.4 7.2 S 48.1 7.6 8.0 7.9 7.4 5.5 S 57.4 5.6 S RENO-TAHOE W /58.0 W 66.1 W Climatic W Data W6.8 W5.8 W71.5 MISSOULA, MT AP, NV (KRNO). 54 30W | 30.8 74.5 83.6 83.2 FRESNO, CA AIRPORT, 53 | 32.6 5.2 N 38.6 5.7 N 49.5 6.7N 61.9 7.4 8.1 8.3 6.1 N 64.6 5.2 N TONOPAH NV (KTPH). N 71.9 N N S7.4 84.8 N6.8 N76.9 GRAND ISLAND, NE 30 83.0 87.1 LONG BEACH, CA 33 5.2 6.0 6.7 7.4 7.1 7.0 6.8 6.6 6.2 5.6 LINCOLN, NE 33.2 S 39.3 S 51.2S 63.5 84.9 89.6 66.5 WINNEMUCCA AP, NV (KWMC). 30 W 73.8 W W W7.9 87.1 W7.7 W78.8 LOS ANGELES 54W | 31.2 6.7 7.4 8.1 8.5 8.4 8.0 7.3 S 64.0 6.9 S NORFOLK, NE AP, CA 30 37.3 48.5 61.3 72.3 82.3 86.5 84.4 76.4 LOS ANGELES C.O., CA 28 6.2 6.4 6.5 6.3 6.0 5.4 5.0 4.9 5.1 5.2 NORTH PLATTE, NE 30 36.5 43.3 52.1 62.7 72.0 82.6 88.4 86.8 78.0 65.6 MOUNT EPPLEY SHASTA,AP, CA NE 3 5.0 5.2 5.8 6.2 5.4 5.4 4.4 4.2 4.6 4.2 OMAHA 30 31.7 37.9 50.4 63.2 73.7 83.7 87.4 85.2 77.3 65.2 REDDING, CA 16 6.2 7.1 7.3 7.0 7.3 7.5 6.6 6.1 6.0 6.0 OMAHA (NORTH), NE 30 32.1 38.0 50.8 63.6 NEW 73.3 82.4 85.6 83.9 76.3 64.6 MEXICO NORMALS 1971-2000 YRS JAN FEB MAR APR MAY JUN JUL AUG SEP OCT SACRAMENTO, CA 52 7.1 7.3 8.4 8.6 9.0 9.6 8.9 8.4 7.4 6.4 SCOTTSBLUFF, NE 30 38.0 44.3 51.7 61.0 71.1 82.2 88.7 86.8 77.3 64.4 BIRMINGHAM AP,AL 30 52.8 58.3 66.5 74.1 81.0 87.5 90.6 90.2 84.6 74.9 SAN DIEGO, CA 62 6.0 6.6 7.5 7.8 7.9 7.8 7.5 7.4 7.1 6.5 VALENTINE, NE 30 33.8 39.4 48.4 59.8 71.2 88.3 86.9 77.2 63.5 PREVAILING WIND81.9 DIRECTION HUNTSVILLE, ALAP, CA 30 48.9 54.6 63.4 72.3 79.6 86.5 89.4 89.0 83.0 72.9 SAN FRANCISCO 75 7.2 8.6 10.5 12.2 13.4 14.0 13.6 12.8 11.1 9.4 ELKO, NV 30 37.1 42.9 51.2 59.3 68.6 79.9 89.6 88.1 78.2 65.0 MOBILE, AL 30 60.7 64.5 71.2 77.4 84.2 89.4 91.2 90.8 86.8 79.2 SAN FRANCISCO C.O., CA 28 6.7 7.5 8.5 9.5 10.4 10.9 11.2 10.5 9.1 7.6 ELY, NV 30 40.0 44.0 49.9 57.9 67.3 79.2 87.3 85.1 75.8 63.0 MONTGOMERY, AL 30 57.6 62.4 70.5 77.5 84.6 90.6 92.7 92.2 87.7 78.7 SANTA BARBARA, CA 31 5.1 5.9 6.7 7.6 7.0 6.7 6.5 6.1 5.5 5.5 LAS VEGAS, NV 30 | 57.1 87.8 JUN 98.9 JUL 104.1 AUG 101.8SEP93.8 STATION JAN 63.0 FEB 69.5 MAR 78.1 APR MAY OCT 80.8 NOV ANCHORAGE, AKCA 30 22.2 25.8 33.6 43.9 54.9 62.3 65.3 63.3 55.0 40.0 SANTA NV MARIA, 22 6.4 7.2 8.1 8.0 8.2 7.8 6.5 6.3 5.9 6.0 RENO, 30 45.5 51.7 57.2 64.1 72.6 82.8 91.2 89.9 81.7 69.9 ANNETTE, AK 30 39.7 41.9 44.7 49.8 55.7 60.3 64.1 64.6 59.6 51.4 STOCKTON, CA 42 6.7 7.0 7.7 8.4 9.2 9.2 8.2 7.7 7.1 6.4 WINNEMUCCA, NV 30 41.6 48.5 55.1 62.6 72.0 82.7 92.2 90.6 80.4 67.3 ALAMOGORDO-HOLLOMAN AFB, NM | S S S S S S S S S S SSE BARROW, 30 -7.7 -9.8 -7.4 6.3 24.9 39.5 46.5 43.6 34.8 19.3 ALAMOSA,AK CO 11 5.6 6.6 8.4 10.3 9.7 9.0 7.0 6.2 6.5 6.4 CONCORD, NH 30 30.6 34.1 43.8 56.9 69.6 77.9 82.9 80.8 72.1 60.5 BETHEL, AK 30 59.4 63.1 COLORADO SPRINGS, 54 9.4 10.0 11.1 11.6 11.2 10.4 9.4 S 35.3 9.6 ALBUQUERQUE-DOUBLE EAGLE II NNW 13.9 NW 21.8 W 49.4 W S S9.3 59.7 S8.9NNW51.7 NNW MT. WASHINGTON, NHCO 30 | 12.4 14.0 14.8 21.3W 33.3 29.4 41.6 50.3 54.1 53.0 46.1 36.4 BETTLES,AK 30 -3.1 2.0 16.4 34.1 54.9 68.7 70.8 63.2 49.1 25.4 DENVER, CO 47 | 41.4 8.6 N 43.9 8.7 N 51.9 9.6N 61.3 10.0 9.3 8.8 7.9 N 66.3 7.8 N ATLANTIC CITY AP, NJ 30 80.0 85.1 ALBUQUERQUE INT'L AP, NM (KA W 71.1 W E E8.3 83.3 E8.0 E76.6 BIG DELTA,AK 30 4.4 10.9 25.1 42.5 57.8 67.3 70.4 64.8 53.2 31.1 GRAND JUNCTION, CO 56 5.7 6.7 8.4 9.4 9.6 9.8 9.4 9.1 9.0 7.9 ATLANTIC CITY C.O.,NJ 30 | 41.4 66.1 SSE 74.8 SSE 80.6 SSE 79.8SSE74.1 ARTESIA WIND WSW 43.2 SSE 49.5 SSE 57.5 SSE SSE SSE 64.5 SSE COLD BAY,AK 30 32.8 32.3 35.1 38.2 44.9 50.8 55.1 56.2 52.5 45.0 PUEBLO, CO AP, NM (KATS). 47 7.8 8.5 9.6 10.3 9.7 9.3 8.7 7.9 7.9 7.4 NEWARK, NJ 30 38.1 41.1 50.1 60.8 71.4 80.2 85.2 83.2 75.7 64.7 CARLSBAD AK AP, NM (KCNM). WIN W 60.6 W SSE S9.4 SSE FAIRBANKS, 30 | -0.3 8.0 W 25.0 70.9 73.0 66.3 BRIDGEPORT, CT 12.5 W 12.9 13.0W 43.6 12.4 11.1 9.9 9.5 S54.3 10.5 S 31.4 11.3 W GULKANA,AK 30 65.0 68.5 HARTFORD, 48 | 3.5 8.9 W 13.8 9.4 N 28.2 9.9N 42.4 9.8 8.7 8.0 7.3 S 34.3 7.8 W CLAYTON CT MUNI AP, NM (KCAO). N 55.6 S S S7.3 64.5 S7.0 S53.4 HOMER, 57.0 61.0 60.8 WILMINGTON, DE 54 9.8 10.3 11.0 10.4 9.0 8.3 7.8 8.1 CLINESAKAKCORNERS, NM (KCQC). 30 |29.3 WNW 31.4 WNW 36.3 W 43.4 W 50.6 W W W7.8 W7.4 W54.8 W 44.1 WNW JUNEAU, 30 30.6 34.3 39.5 48.1 55.7 61.6 64.3 63.1 56.1 46.9 WASHINGTON DULLES AP, D.C. 40 8.1 8.6 9.0 8.8 7.4 6.8 6.2 5.8 6.2 6.6 CLOVIS MUNI (KCVN). 30 W 52.1 S S S8.3 62.2 S8.1 S54.9 lwf.ncdc.noaa.gov/oa/climate/online/ccd/maxtemp.html KING SALMON, AK AP, 59.5 63.8 WASHINGTON NAT'L AP, NM D.C. 54 | 22.8 10.0 W 23.8 10.3 W 32.0 10.9W 41.3 10.5 9.3 8.9 8.3 S 40.5 8.7 W KODIAK, AK 30 54.5 59.6 61.4 APALACHICOLA, FL 54 8.3 8.7 8.9 8.5 7.7 7.1 7.8 8.0 CLOVIS-CANNON AFB, NM (KCVS) |34.7 W 35.5 W 38.3 W 42.7 W 48.8 S S S6.4 S6.4 S55.6 W 46.2 W KOTZEBUE, AK 30 3.7 3.0 7.2 19.6 37.8 50.8 60.0 56.7 46.4 27.5 DAYTONA BEACH, FL 57 8.8 9.3 9.8 9.4 8.9 8.0 7.3 7.0 8.0 8.9 MCGRATH, AK FL 30 2.3 10.7 25.3 40.5 56.8 67.6 69.7 64.1 53.4 32.2 FORT MYERS, 57 8.3 8.9 9.3 8.8 8.0 7.2 6.6 6.7 7.4 8.4 NOME, AK 30 13.4 13.6 17.7 26.8 43.0 53.9 58.6 56.0 48.6 34.0 GAINESVILLE, FL 19 6.9 7.4 7.8 7.2 6.9 6.1 5.6 5.4 5.8 6.3 ST. PAUL ISLAND, 30 29.8 27.6 28.8 32.8 39.8 46.2 50.3 51.6 49.2 42.5 JACKSONVILLE, FL AK 53 8.1 8.7 9.1 8.5 7.9 7.7 7.0 6.7 7.4 7.8 TALKEETNA, AK 30 19.6 25.7 34.0 44.6 56.7 65.4 67.9 64.6 55.1 39.1 KEY WEST, FL 49 11.8 12.0 12.1 12.2 10.5 9.6 9.4 9.2 9.6 10.8 www.wrcc.dri.edu/htmlfiles/westwinddir.html UNALAKLEET, AK 30 10.5 12.7 19.6 31.5 46.9 55.2 62.0 59.6 51.3 33.6 MIAMI, FL 53 9.5 10.0 10.5 10.5 9.5 8.3 7.9 7.9 8.2 9.2 VALDEZ, 30 26.6 30.0 35.8 44.4 52.9 59.4 62.3 60.8 53.3 43.0 ORLANDO,AK FL 54 9.0 9.6 9.9 9.4 8.8 8.0 7.3 7.2 7.6 8.6 YAKUTAT, AKFL 30 32.1 35.7 39.3 45.1 51.1 56.6 60.1 60.4 55.7 47.3 PENSACOLA, 38 9.0 9.3 9.8 9.5 8.6 7.6 6.9 6.7 7.6 7.9 FLAGSTAFF, AZFL 30 42.9 45.6 50.3 58.4 67.6 78.7 82.2 79.7 73.8 63.1 TALLAHASSEE, 41 6.7 7.1 7.5 6.8 6.2 5.7 5.0 5.0 5.9 6.3 PHOENIX, 30 65.0 69.4 74.3 83.0 91.9 97.4 86.4 TAMPA, FLAZ 56 8.6 9.1 9.4 9.2 8.6 102.0 7.9 104.2 7.1 102.4 6.9 7.6 8.3 TUCSON, AZ FL 30 64.5 68.4 73.3 81.5 90.4 99.6 97.4 94.0 84.0 VERO BEACH, 19 8.7 9.0 9.9 9.5 9.1 100.2 7.7 6.9 6.5 7.3 8.6 WINSLOW, 30 47.1 54.4 61.5 69.8 79.0 90.0 93.0 90.1 83.5 71.7 WEST PALMAZ BEACH, FL 60 10.1 10.5 11.0 10.9 9.9 8.3 7.7 7.7 8.7 10.0 YUMA, AZGA 30 69.9 75.2 80.1 87.2 94.7 90.3 ATHENS, 47 8.3 8.6 8.7 8.3 7.1 104.4 6.6 107.3 6.3 106.1 5.8 101.0 6.4 6.6
Phase 5 Design Guideline Cooling Analysis • CROSS VENTILATION
11.0 11.3 11.4 11.0 11.8 13.7 11.9 9.7 12.1 9.7 7.0 9.9 8.9 8.2 7.4 8.8 8.7 8.3 10.0 8.8 8.8 16.2 12.7 70.5 10.4 80.7 8.5 84.3 11.2 84.1 11.2 81.0 10.5 47.5 9.6 46.8 10.7 N 44.5 11.9 SSE 47.1 9.7 S 48.0 11.6 48.8 9.4 45.5 11.0 50.9 13.6 55.7 8.6 48.5 6.9 51.6 6.1 47.7 6.9 46.7 10.6 DEC 43.6 11.2 44.8 10.2 45.0 11.0 W 51.0 12.2 SW 54.5 9.5 SSE 49.6 14.5 S 53.1 10.6 WSW 54.5 7.1 53.6 5.3 S 56.4 5.0 ESE 54.5 11.8 S 55.9 9.9 57.2 SW 11.4 70.1 9.5 SW 70.6 10.9 SW NOV 71.0 9.7 7.2 66.8 10.2 W 8.1 37.4 9.7 W 8.9 47.1 5.1 6.5 S 56.3 9.9 SW 6.4 49.3 7.8 11.7 WSW 51.8 5.5 12.5 47.1 7.2 S 14.9 42.2 6.6 ESE 13.2 47.8 39.5 SSW 5.8 46.3 9.9 10.2 45.5 10.2 W 17.5 41.9 7.9 3.8 46.0 11.8 4.1 35.4 7.7 7.7 45.6 9.1 8.4 38.9 10.4 35.2 12.5 32.5 14.4 40.1 DEC 3.7 38.7 11.5 37.2 20.0 66.3 NNE 5.0 68.5 NNE 7.5 63.0 7.2 E 53.4 6.6 52.0 S 5.3 53.8 S 8.1 56.4 7.3 S 42.7 6.9 37.4 W 7.8 NE 42.1 8.0 40.8 NE 5.1 41.5 NW 6.6 38.6 6.0 S 40.0 4.7 N 46.8 5.2 49.1 6.7 S 45.5 5.8 48.5 5.2 47.8 5.7 47.5 NOV 6.0 48.2 64.5 5.9 45.9 61.6 7.5 48.1 70.1 6.3 48.8 68.7 5.2 66.0 DEC 27.7 6.4 55.3 44.2 5.8 51.4 4.6 5.6 N 47.6 23.1 9.5 NNW 27.6 6.4 8.2 N 56.0 13.5 6.8 55.0 N 39.1 7.5 53.7 11.2 12.0 W 13.2 8.4 WSW 35.2 9.2 WNW 37.6 7.6 30.5 9.4 W 39.0 8.0 W 13.3 8.3 13.8 8.1 23.0 6.2 37.1 7.6 25.6 12.0 20.2 9.7 32.7 8.6 38.4 8.2 50.8 5.9 73.3 8.2 72.3 8.6 57.7 10.4 77.3 7.3
11.2 11.1 11.0 11.0 11.5 13.4 11.9 9.5 11.7 10.0 7.1 10.3 9.1 8.4 8.1 9.3 9.0 8.8 10.4 9.0 8.9 16.7 13.4 62.6 10.9 79.5 8.4 81.7 11.3 81.7 11.3 79.0 10.7 37.2 9.3 39.2 | 11.0 33.8 11.7 | 34.4 9.6 | 34.5 11.2 35.5 8.8 32.0 10.4 38.0 13.7 44.1 8.2 35.8 7.8 39.2 6.9 35.6 7.5 33.1 10.6 | 29.7 10.9 31.7 10.3 | 30.7 11.2 39.6 13.0 | 44.4 9.7 | 41.3 15.2 | 40.9 10.8 | 43.1 6.7 42.7 5.1 | 46.3 4.7 | 44.3 11.6 | 45.4 9.6 46.3 | 11.3 62.8 9.0 | 63.3 10.7 | DEC 64.5 9.8 7.7 | 58.5 10.4 9.0 24.8 | 9.2 9.6 36.4 5.0 | 7.1 46.0 9.9 | 6.3 38.6 7.3 12.0 | 41.7 5.3 11.7 36.2 | 7.4 13.9 31.2 7.0 | 13.6 35.9 44.5 | 5.6 34.2 10.3 10.0 | 33.7 10.8 17.5 30.5 7.6 3.0 34.1 12.1 3.3 24.1 7.6 7.8 34.6 9.3 8.8 27.2 10.1 22.3 12.6 18.1 12.9 26.4 | 3.2 24.5 10.3 23.2 20.1 57.9 | 4.9 60.5 | 7.0 53.6 7.8 | 41.5 6.6 | 40.0 5.1 42.0 | 7.8 45.5 | 6.7 34.5 7.2 | 24.8 8.1 | 34.2 8.1 30.1 | 5.0 31.5 | 6.7 30.1 6.4 | 30.3 4.9 | 35.3 5.0 36.8 | 6.6 33.6 5.8 39.2 5.4 34.8 6.4 35.1 DEC 6.4 39.8 56.0 5.6 36.7 52.4 7.1 38.2 62.9 6.5 41.0 60.3 4.4 57.3 | 23.7 6.2 46.4 40.7 6.4 42.2 | -4.7 4.9 35.6 15.6 9.4 | 18.5 0.4 8.4 46.4 | 7.2 6.0 46.3 | 35.5 7.7 43.0 | 3.3 12.1 6.4 8.7 | 31.6 9.3 | 33.0 7.7 | 25.1 9.6 35.8 8.0 | 6.0 8.3 4.8 7.9 15.8 6.0 32.9 7.6 21.2 11.8 13.6 9.1 29.1 8.5 34.3 8.8 43.7 6.3 65.0 8.3 64.6 8.0 47.1 10.0 69.0 8.0
10.2 10.7 11.0 10.5 11.9 13.9 12.5 9.6 12.2 9.0 6.4 9.1 8.3 7.4 7.5 8.4 8.2 8.3 10.0 8.7 8.8 15.3 12.4 77.2 10.1 81.0 8.1 84.7 10.3 84.3 10.2 81.1 9.8 62.6 8.7 62.4 N9.9 59.6 10.6 S 58.3 9.2 SSW 60.4 11.0 60.7 8.8 57.8 10.5 62.4 12.9 66.7 8.3 59.6 7.0 62.3 6.2 58.8 6.8 59.8 ANN9.8 56.0 10.6 59.6 9.6 W 58.1 10.4 64.5 11.2 SW 67.7 10.7 SSE 63.9 12.5 S 65.2 10.2 WSW 67.4 7.7 64.0 S6.2 65.2 6.2 E 64.7 11.8 S 66.0 10.1 67.5 SW 11.2 77.3 10.1 SW 77.6 10.5 SW ANN 78.0 9.1 W7.1 76.3 10.5 48.9 W7.9 9.8 8.8 55.2 5.9 S6.6 65.1 10.3 W7.1 57.7 9.2 10.1 W6.6 59.3 12.0 55.9 NW 8.0 13.2 52.6 6.7 NW 12.6 58.4 35.1 S 6.5 56.8 9.8 W8.5 56.9 10.2 16.8 53.7 8.9 5.4 56.9 12.2 6.5 48.0 8.7 7.6 55.8 8.9 8.2 49.6 10.5 48.7 11.0 48.8 12.8 54.7 ANN 5.22/4 52.6 10.4 52.5 16.9 75.0 S4.8 76.9 SSW 6.1 72.7 W7.1 64.9 S6.4 64.3 65.7 S6.2 8.3 67.4 S8.8 58.4 7.8 S 54.0 S7.6 56.4 7.8 56.6 NNE 6.4 56.7 NW 6.7 54.6 6.8 W 56.7 N6.4 61.1 6.2 62.8 S7.5 60.3 5.7 63.0 5.1 61.5 6.6 61.1 ANN 7.8 62.8 73.4 7.0 61.1 71.1 10.6 62.2 77.4 8.7 61.6 77.0 6.0 79.9 ANN 43.1 6.9 67.4 51.4 7.5 65.6 S7.2 15.8 57.7 36.6 10.0 W 33.9 32.4 63.6 N8.6 37.4 8.2 61.1 SSE 43.1 8.5 62.3 S 37.3 11.4 37.4 S8.4 44.6 W9.0 47.6 7.4 S9.42/4 42.4 46.0 W7.8 27.7 8.5 36.8 8.0 33.7 6.5 39.1 7.8 43.3 10.96/9 34.7 9.2 44.2 8.5 46.3 8.3 61.4 6.2 84.5 8.3 82.5 8.3 70.4 9.6 88.5 7.3
To rely on cross ventilation as a cooling strategy during summer months in Las Vegas is simply unrealistic. The average daily high in the months of June, July and August is 99, 104, and 101°F. Las Vegas’ summer design temperature is 106°F, which means hurricane force winds would be required to make cross ventilation bearable. Assuming a 3°F difference between internal and external temperatures, the internal summer design temp would then be 109°F, which is far from the comfort zone. However, spring and fall present opportunities for using cross ventilation when the prevailing winds are from the west and southwest (versus south in the summer) and average about 10mph. Also a consideration for cross (and stack) ventilation is that buses and cars are queuing relatively close to the south side of the building (prevailing summer wind direction) and summer cross/stack ventilation would bring those fumes into the building. Total Heat Gains “Open “ (from Phase 4) = 30.1 Btu/h ft Wind Velocity for cooling months of July and August = 11mph Required Inlet area as percentage of floor area = 35sf/1,720 = 2%
Wind- Average Wind Speed- (MPH)
Source: National Climatic Data Center http://lwf.ncdc.noaa.gov/oa/climate/online/ccd/avgwind.html
Source: Western Regional Climate Center http://www.wrcc.dri.edu/htmlfiles/westwinddir.html
Normal Daily Maximum Temperature, Deg F
Source: National Climatic Data Center http://lwf.ncdc.noaa.gov/oa/climate/online/ccd/avgwind.html
30
Cross Ventilation (cont.)
Source: MEEB Figure 8.13 • STACK VENTILATION The same issue which arises with cross ventilation is present with using stack ventilation as a summer cooling strategy. The exterior temperature is simply too hot during the summer days to use to cool the building, but it is a viable option for more temperate months such as March, April October and November. Also, to be effective the stack must be substantial in size; 155sf in area by 40ft tall. Total Heat Gains “Open “ (from Phase 4) = 30.1 Btu/h ft2 Stack Height = 40ft Required stack area as percentage of floor area = 155sf/1,720 = 9%
Source: MEEB Figure 8.14 31
SPRINGFIELD, IL 30 17.1 22.2 32.4 42.2 52.7 61.9 66.0 63.9 EVANSVILLE, IN 30 22.6 26.2 35.2 43.8 54.0 63.5 67.8 65.1 FORT WAYNE, IN 30 16.1 19.2 28.8 38.2 49.1 58.8 62.5 60.4 INDIANAPOLIS, IN 30 18.5 22.5 32.0 41.2 51.8 61.3 65.2 63.3 SOUTH BEND, IN 30 15.7 19.0 28.2 37.7 48.4 58.3 62.8 61.3 DES MOINES, IA 30 11.7 17.8 28.7 39.9 51.4 61.0 66.1 63.9 DUBUQUE,IA 30 9.2 15.4 26.2 37.5 48.8 57.9 62.4 60.2 SIOUX CITY, IA 30 8.5 15.3 25.7 37.3 49.2 58.5 62.9 60.6 WATERLOO, IA 30 6.3 13.2 24.9 35.8 48.1 58.1 62.2 59.5 CONCORDIA, KS 30 16.9 21.9 31.1 41.2 51.9 61.8 67.4 65.6 DODGE CITY, KS 30 18.7 23.6 31.2 40.7 51.7 61.6 66.8 65.6 GOODLAND, KS 30 15.8 19.7 26.4 34.8 45.7 55.5 61.1 59.6 TOPEKA, KS 30 17.2 23.0 32.9 42.9 53.4 63.2 67.7 65.4 WICHITA, KS 30 20.3 25.3 34.4 43.7 54.0 63.9 69.1 67.9 GREATER CINCINNATI AP 30 21.3 25.0 33.8 42.7 52.9 61.6 66.1 64.2 JACKSON, KY 30 25.7 28.9 37.4 45.8 54.3 61.9 65.7 64.3 LEXINGTON, KY 30 24.1 27.7 35.9 44.1 53.6 62.2 66.4 64.9 LOUISVILLE, KY 30 24.9 28.5 37.1 46.0 56.1 65.1 69.8 68.2 PADUCAH KY 30 23.9 28.2 37.1 45.6 55.0 63.8 67.7 64.9 BATON ROUGE, LA 30 40.2 43.1 49.6 55.8 64.1 70.2 72.7 71.9 LAKE CHARLES, LA 30 41.2 44.3 50.8 57.2 65.7 72.1 74.3 73.6 NEW ORLEANS, LA 30 43.4 46.1 52.7 58.4 66.4 72.0 74.2 73.9 SHREVEPORT, LA 30 36.5 40.3 47.2 53.8 62.7 69.9 73.4 72.3 CARIBOU, ME 30 -0.3 2.9 15.2 29.2 40.7 49.9 54.8 52.6 PORTLAND, ME 30 12.5 15.6 25.2 34.7 44.2 52.9 58.6 57.2 BALTIMORE, MD 30 23.5 26.1 33.6 42.0 51.8 60.8 65.8 63.9 BLUE HILL, MA 30 18.1 20.3 27.8 37.1 47.0 55.9 62.0 60.9 BOSTON, MA 30 22.1 24.2 31.5 40.5 50.2 59.4 65.5 64.5 WORCESTER, MA 30 15.8 17.8 25.6 35.5 46.2 55.0 60.8 59.5 ALPENA, MI 30 9.5 9.7 18.7 30.2 40.0 48.8 54.5 52.9 DETROIT, MI 30 17.8 20.0 28.5 38.4 49.4 58.9 63.6 62.2 FLINT, MI 30 13.3 15.3 24.3 34.6 45.2 54.6 59.1 57.4 GRAND RAPIDS, MI 30 15.6 17.4 25.9 36.1 46.6 55.8 60.5 59.0 HOUGHTON LAKE, MI 30 9.7 10.5 19.2 30.6 40.7 48.9 53.4 52.2 LANSING, MI 30 13.9 15.4 24.3 34.5 44.8 54.3 58.4 57.0 MARQUETTE, MI 30 3.3 5.4 14.3 26.9 39.1 48.3 53.5 52.0 MUSKEGON, MI 30 17.1 18.3 25.4 35.1 45.1 54.2 59.8 58.8 SAULT STE. MARIE, MI 30 4.9 6.6 16.1 28.8 39.3 46.5 52.0 52.4 DULUTH, MN 30 -1.2 5.1 16.5 28.9 40.2 48.5 54.6 53.5 INTERNATIONAL FALLS, MN 30 -8.4 -0.7 12.3 27.1 40.0 49.1 53.6 51.3 MINNEAPOLIS-ST.PAUL, MN 30 4.3 11.8 23.5 36.2 48.5 57.8 63.0 60.8 ROCHESTER, MN 30 3.7 10.6 22.6 34.6 46.1 55.6 60.1 58.0 SAINT CLOUD, MN 30 -1.2 6.4 19.1 32.2 44.1 52.9 57.9 55.5 JACKSON, MS 30 35.0 38.2 45.4 51.7 61.0 68.1 71.4 70.3 MERIDIAN, MS 30 34.7 37.7 44.3 50.4 59.5 66.8 70.5 69.8 TUPELO, MS 30 30.5 33.5 41.4 48.2 57.7 65.7 69.8 68.2 COLUMBIA, MO 30 18.2 23.4 33.0 42.9 52.8 61.8 66.3 64.0 KANSAS CITY, MO 30 17.8 23.3 33.2 43.5 53.9 63.2 68.2 66.1 ST. LOUIS, MO 30 21.2 26.5 36.2 46.5 56.6 65.9 70.6 68.6 SPRINGFIELD, MO 30 21.8 26.4 34.9 43.6 53.4 62.2 67.1 65.6 BILLINGS, MT 30 15.1 20.1 26.4 34.7 44.0 52.5 58.3 57.3 GLASGOW, MT 30 1.8 9.9 20.6 32.2 43.0 51.6 56.6 55.7 GREAT FALLS, MT 30 11.3 15.1 21.5 29.7 38.3 46.0 50.4 49.9 30 3.7 Daily 10.4Minimum 20.0 Temperature, 30.0 40.2 52.0 51.3 11/1/11HAVRE, MT Normal Deg F 48.0 HELENA, MT 30 9.9 15.6 23.5 31.2 39.8 47.5 52.3 50.8 KALISPELL, MT 30 13.8 18.4 24.8 30.8 37.9 43.5 46.7 45.8 NCDC /20.5 Get/View Data /32.4 Comparative / Search MISSOULA, MT 30 16.2 27.1 39.3 Climatic 45.9 Data 50.2 49.3 GRAND ISLAND, NE 30 12.2 17.7 27.0 37.8 49.3 59.1 64.4 62.3 LINCOLN, NE 30 11.5 17.2 27.5 38.8 50.1 60.4 65.9 63.7 NORFOLK, NE 30 9.6 15.5 25.4 36.8 48.3 58.0 63.0 61.0 NORTH PLATTE, NE 30 9.9 15.4 23.8 33.4 44.5 54.2 60.2 58.4 OMAHA EPPLEY AP, NE 30 11.6 18.0 28.1 39.6 50.7 60.6 65.9 63.8 OMAHA (NORTH), NE 30 12.6 19.0 28.8 40.3 51.3 60.5 65.5 64.1 NORMALS 1971-2000 YRS JAN FEB MAR APR MAY JUN JUL AUG SCOTTSBLUFF, NE 30 11.0 15.8 23.0 31.4 42.4 52.1 57.4 54.9 BIRMINGHAM 30 32.3 35.4 42.4 48.4 57.6 65.4 69.7 68.9 VALENTINE, AP,AL NE 30 7.8 13.7 22.1 32.4 43.7 53.2 59.1 57.3 HUNTSVILLE, AL 30 30.7 34.0 41.2 48.4 57.5 65.4 69.5 68.1 ELKO, NV 30 14.1 19.7 25.9 29.9 36.8 43.5 48.6 47.0 MOBILE, 30 39.5 42.4 49.2 54.8 62.8 69.2 71.8 71.7 ELY, NV AL 30 10.4 15.6 21.9 26.4 33.4 40.6 47.4 46.4 MONTGOMERY, AL 30 35.5 38.6 45.4 51.2 60.1 67.3 70.9 70.1 LAS VEGAS, NV 30 36.8 41.4 47.0 53.9 62.9 72.3 78.2 76.7 ANCHORAGE, AK 30 9.3 11.7 18.2 28.7 38.9 47.0 51.5 49.4 RENO, NV 30 21.8 25.4 29.3 33.2 40.2 46.5 51.4 49.9 ANNETTE, AK 30 30.4 32.3 34.2 37.7 43.1 48.3 52.4 52.6 WINNEMUCCA, NV 30 18.5 23.6 27.0 30.7 38.4 45.8 51.8 49.2 BARROW, AK 30 -19.6 -7.3 15.3 30.4 34.3 33.8 CONCORD, NH 30 9.7 -22.0 12.6 -20.0 22.7 32.2 42.4 51.8 57.1 55.6 BETHEL, AK 30 0.7 1.3 7.2 18.4 33.1 43.3 48.8 47.5 MT. WASHINGTON, NH 30 -3.7 -1.7 5.9 16.4 29.5 38.5 43.3 42.1 BETTLES,AK 30 -19.2 -8.0 10.6 33.7 46.9 49.5 43.7 ATLANTIC CITY AP, NJ 30 22.8 -17.7 24.5 31.7 39.8 49.8 59.3 65.4 63.7 BIG DELTA,AK 30 -9.6 -6.4 3.2 21.7 37.7 47.6 51.1 46.1 ATLANTIC CITY C.O.,NJ 30 29.0 30.6 37.0 45.2 54.8 63.9 69.8 69.7 COLD BAY,AK 30 23.5 22.9 24.9 28.8 34.8 41.1 46.1 47.4 NEWARK, NJ 30 24.4 26.6 34.2 43.7 54.1 63.5 69.1 67.7 FAIRBANKS, AK 30 -19.0 -15.6 -2.7 19.8 36.9 48.5 51.9 46.2 GULKANA,AK 30 -12.9 -7.4 2.3 19.7 32.2 41.1 45.4 41.7 HOMER, AK 30 17.5 18.3 22.5 29.3 36.7 43.0 47.2 46.7 JUNEAU, AK 30 20.7 23.5 27.8 33.4 40.1 46.1 49.2 48.3 www.ncdc.noaa.gov/oa/climate/online/ccd/mintemp.html KING SALMON, AK 30 8.0 7.4 15.1 24.9 34.8 42.2 47.5 47.4 KODIAK, AK 30 24.6 24.3 26.8 31.8 38.2 43.9 48.5 48.6 KOTZEBUE, AK 30 -8.6 -9.9 -7.7 3.3 25.3 38.8 49.4 47.4 MCGRATH, AK 30 -15.6 -12.5 -1.8 17.7 35.5 45.7 49.8 45.7 NOME, AK 30 -1.8 -2.3 1.0 12.4 31.1 40.6 46.6 45.2 ST. PAUL ISLAND, AK 30 21.5 18.9 19.5 24.0 31.5 37.6 43.0 45.1 TALKEETNA, AK 30 2.3 5.0 11.1 23.9 34.9 45.1 49.9 46.5 UNALAKLEET, AK 30 -3.9 -4.2 1.8 13.8 32.1 42.7 48.9 46.5 VALDEZ, AK 30 17.2 19.6 23.8 30.9 38.6 45.0 48.0 46.4 YAKUTAT, AK 30 19.4 21.0 23.6 29.2 36.1 42.7 47.1 46.2 FLAGSTAFF, AZ 30 16.5 18.8 22.8 27.3 34.0 41.4 49.9 49.1 PHOENIX, AZ 30 43.4 47.0 51.1 57.5 66.3 75.2 81.4 80.4 TUCSON, AZ 30 38.9 41.6 45.1 50.5 58.6 68.0 73.4 72.4 WINSLOW, AZ 30 21.3 25.5 31.1 36.9 45.3 54.2 62.0 61.1 YUMA, AZ 30 46.2 48.8 52.8 58.1 65.1 73.2 80.8 80.8 FORT SMITH, AR 30 27.8 32.6 40.9 49.0 58.9 67.2 71.4 70.3 LITTLE ROCK, AR 30 30.8 34.8 42.6 50.0 59.2 67.8 72.0 70.5 NORTH LITTLE ROCK, AR 30 31.3 36.1 44.5 52.7 61.2 68.9 72.9 71.5 BAKERSFIELD, CA 30 39.3 43.0 46.2 49.6 56.8 63.7 69.2 68.4 BISHOP, CA 30 22.4 26.4 31.0 36.0 43.7 50.7 55.7 53.7 EUREKA, CA. 30 40.8 41.8 42.2 44.0 47.6 50.7 52.8 53.4 FRESNO, CA 30 38.4 41.4 44.9 48.4 54.9 61.2 66.1 64.9 LONG BEACH, CA 30 46.0 48.1 50.4 53.2 57.8 61.3 64.6 65.6 LOS ANGELES AP, CA 30 48.6 50.1 51.3 53.6 56.9 60.1 63.3 64.5 LOS ANGELES C.O., CA 30 48.5 50.3 51.6 54.4 57.9 61.4 64.6 65.6 MOUNT SHASTA, CA 30 26.4 28.7 30.3 33.3 39.0 44.9 48.9 47.5 REDDING, CA 30 35.5 38.1 41.1 44.9 51.6 59.6 64.1 60.8 SACRAMENTO, CA 30 38.8 41.9 44.2 46.3 50.9 55.5 58.3 58.1 SAN DIEGO, CA 30 49.7 51.5 53.6 56.4 59.8 62.6 65.9 67.4 SAN FRANCISCO AP, CA 30 42.9 45.5 46.8 48.1 50.5 52.9 54.5 55.5 SAN FRANCISCO C.O., CA 30 46.4 48.5 49.2 50.1 51.4 53.2 54.4 55.6 SANTA BARBARA, CA 30 40.8 44.0 46.0 47.6 50.5 53.9 57.3 58.4 SANTA MARIA, CA 30 39.3 41.4 42.7 43.4 46.9 50.4 53.5 54.2 STOCKTON, CA 30 38.1 41.0 43.6 46.7 52.1 57.5 60.8 60.3 ALAMOSA, CO 30 -3.7 4.7 15.8 22.8 32.4 40.4 46.4 45.2 COLORADO SPRINGS, CO 30 14.5 18.0 23.9 31.4 40.7 49.5 54.8 53.6 DENVER, CO 30 15.2 19.1 25.4 34.2 43.8 53.0 58.7 57.4 GRAND JUNCTION, CO 30 15.6 22.7 31.0 37.5 46.4 55.3 61.4 59.7 PUEBLO, CO 30 14.0 18.8 26.3 34.5 44.8 53.5 59.4 58.1 BRIDGEPORT, CT 30 22.9 24.9 32.0 40.7 50.6 59.6 66.0 65.4 HARTFORD, CT 30 17.2 19.9 28.3 37.9 48.1 57.0 62.4 60.7 WILMINGTON, DE 30 23.7 25.8 33.4 42.1 52.4 61.8 67.3 65.8 WASHINGTON DULLES AP, D.C. 30 21.9 24.1 31.8 40.2 49.9 59.0 64.0 62.8 WASHINGTON NAT'L AP, D.C. 30 27.3 29.7 37.3 45.9 55.8 65.0 70.1 68.6 APALACHICOLA, FL 30 43.0 45.8 51.4 57.6 65.1 71.6 73.9 74.0 DAYTONA BEACH, FL 30 47.1 48.8 53.7 58.0 64.5 70.6 72.4 72.8 FORT MYERS, FL 30 54.5 55.4 59.3 62.7 68.4 73.1 74.2 74.4 GAINESVILLE, FL 30 42.4 44.7 49.9 54.7 62.0 68.4 70.8 70.6 JACKSONVILLE, FL 30 41.9 44.3 49.8 54.6 62.5 69.4 72.4 72.2 KEY WEST, FL 30 65.2 65.7 68.8 72.1 75.9 78.7 79.6 79.2
• NIGHT VENTILATION OF MASS
55.4 57.0 52.8 55.2 53.3 54.3 51.7 50.1 49.8 56.1 56.5 50.0 55.9 59.3 56.8 58.4 57.9 60.9 57.1 67.5 69.1 70.6 66.4 43.6 48.5 56.6 53.2 56.8 51.3 45.2 54.1 49.4 51.0 45.3 48.9 43.8 50.7 44.8 44.8 41.6 50.8 48.7 45.7 64.6 64.2 61.7 55.4 57.2 60.3 57.4 47.1 44.1 41.2 40.7 41.2 37.1 40.6 51.8 53.2 50.4 46.7 53.5 55.0 SEP 43.7 63.0 45.8 61.7 38.1 67.6 37.5 64.9 68.8 41.4 43.1 48.0 40.2 27.5 46.6 39.1 34.6 32.8 56.0 35.6 63.6 43.0 59.9 34.7 32.8 41.0 43.8 40.3 43.2 37.2 35.9 37.2 40.7 37.3 35.8 40.9 40.6 41.7 74.5 67.7 52.9 75.3 62.9 63.6 64.9 63.9 46.9 51.2 60.4 63.7 63.6 64.6 42.9 56.5 55.8 66.1 55.1 56.1 56.6 52.9 57.4 36.5 45.4 47.3 50.4 48.7 57.7 52.1 58.1 55.6 61.8 71.2 71.9 73.9 68.1 69.4 78.5
44.4 44.6 41.8 43.6 42.3 42.2 40.5 38.0 37.8 44.0 43.8 37.5 44.3 46.9 44.9 47.4 46.4 48.5 45.2 56.4 58.6 60.2 55.0 34.1 37.4 43.7 42.9 46.4 40.7 35.6 42.5 38.6 40.2 36.2 38.6 34.0 40.6 36.0 34.5 31.5 38.9 37.1 34.3 52.0 51.3 48.8 44.1 45.9 48.2 46.1 37.2 33.0 33.0 29.8 31.2 28.4 31.4 39.3 40.4 38.0 33.7 41.1 43.1 OCT 31.3 50.9 33.1 49.6 28.3 56.3 27.8 52.2 56.5 28.3 34.0 41.7 30.2 9.8 35.1 24.7 24.0 11.9 43.9 17.0 52.5 35.1 48.2 15.6 18.4 31.4 37.7 26.0 34.3 18.8 18.3 22.9 34.1 23.6 19.4 33.4 34.8 31.1 62.9 57.0 40.1 64.0 50.5 51.5 54.1 54.9 37.1 47.7 51.9 58.3 59.4 59.9 36.6 48.0 50.6 61.2 52.4 54.6 51.6 48.2 50.5 23.9 34.3 35.9 38.6 35.3 46.3 40.6 45.6 42.3 49.6 60.5 65.3 68.6 59.2 59.7 75.7
33.7 36.0 32.7 34.1 32.6 29.0 27.8 24.8 25.1 30.5 30.2 25.2 32.1 33.9 35.7 38.9 37.3 39.3 36.5 47.9 49.7 51.8 45.3 23.7 29.5 34.7 34.2 37.9 32.0 27.0 33.5 29.8 31.2 27.6 30.1 22.4 31.8 25.9 20.7 16.4 24.8 23.7 20.4 43.4 42.8 40.0 33.0 33.4 36.7 35.3 25.6 18.5 22.5 17.3 20.3 23.2 24.0 25.9 27.0 24.7 20.7 28.1 29.2 NOV 19.7 41.8 20.1 40.7 20.9 47.8 18.2 43.5 44.0 15.9 26.4 35.1 23.3 -6.4 27.6 11.7 13.6 -8.0 35.7 -0.8 42.9 29.9 39.1 -6.6 -2.2 23.5 28.9 15.9 28.9 3.2 -2.2 10.8 29.1 9.4 5.0 23.9 26.3 22.1 50.0 45.1 28.7 52.2 39.5 41.5 43.4 44.2 27.1 43.9 42.3 50.1 52.7 52.6 29.9 39.8 42.8 53.6 47.5 50.8 44.0 41.8 42.1 11.1 22.6 23.5 26.3 22.5 37.5 32.6 36.9 33.8 40.0 52.0 57.0 62.1 51.1 50.8 71.9
22.6 27.0 22.3 24.0 21.7 16.7 15.2 12.8 12.5 20.8 21.7 17.8 21.8 24.0 26.4 30.2 28.4 29.9 27.5 42.1 43.3 45.6 38.3 8.0 18.7 27.3 23.8 27.8 21.6 16.9 23.4 19.1 21.4 16.8 19.7 10.2 22.6 13.1 5.6 -1.1 10.9 10.1 5.5 37.3 37.2 33.2 22.5 22.5 25.8 25.9 17.7 6.4 14.4 7.8 11.3 16.1 16.5 15.9 16.2 13.7 12.1 16.4 17.2 DEC 11.6 35.2 10.5 33.8 13.8 41.6 10.6 37.6 36.6 11.4 20.7 32.1 17.0 -16.4 16.2 3.2 1.7 -15.1 27.1 -7.1 34.0 26.5 29.8 -15.2 -9.5 20.0 24.4 9.3 25.3 -6.4 -12.3 0.9 24.7 4.8 -1.4 20.2 22.9 16.6 43.5 39.2 21.0 45.8 31.1 33.9 34.9 38.2 21.6 40.6 37.0 45.3 48.5 48.3 25.8 35.0 37.7 48.9 43.0 46.7 39.9 38.2 36.7 -0.7 15.6 16.4 17.5 15.1 28.0 22.6 28.4 26.0 32.0 45.3 50.1 56.2 44.4 44.1 67.3
42.9 45.2 40.2 42.7 40.1 40.2 37.7 37.0 36.1 42.4 42.7 37.4 43.3 45.2 44.3 46.6 45.7 47.9 46.1 56.8 58.3 59.6 55.1 29.6 36.3 44.2 40.3 43.9 38.5 32.4 41.0 36.7 38.4 32.6 36.7 29.4 38.3 30.5 29.3 26.1 35.9 34.3 31.1 53.2 52.4 49.9 43.1 44.0 46.9 45.0 36.3 31.1 31.1 29.3 31.2 30.5 32.8 38.6 39.3 37.1 34.4 39.8 40.6 ANN 32.9 50.9 33.2 50.1 30.6 56.2 28.0 53.1 56.3 29.3 35.2 40.7 33.0 5.0 34.1 23.3 20.4 13.4 43.3 19.7 49.4 33.7 46.7 16.3 16.8 31.4 35.3 26.62/4 34.9 15.9 17.0 20.4 30.8 24.5 19.7 32.3 32.5 30.9 61.1 54.8 40.0 61.9 50.2 51.5 53.0 53.1 37.7 46.4 51.0 55.4 56.1 56.6 36.2 47.9 48.4 58.1 49.6 51.4 49.2 46.1 48.9 22.9 33.7 35.8 38.5 35.9 44.3 40.0 45.1 42.6 48.6 59.3 61.0 65.2 57.2 57.6 73.2
While Las Vegas has a high MDR (30°F), an indicator that night ventilation of mass is appropriate in this climate, the summer nights remain warm and therefore would prohibit the flushing of the mass from June through September. Potential for this approach exists for the months of April, May, October and November.
Normal Daily Minimum Temperature, Deg F
Source: National Climatic Data Center http://www.ncdc.noaa.gov/oa/climate/online/ccd/mintemp.html • COOLTOWER
One potential cooling strategy for this hot, dry climate is a cooltower. From the start, it should be noted that there is a trade-off involved, because in a climate where water is a precious resource this method relies on water as the main vehicle for cooling. There are several reasons however, this solution is attractive. First, the Las Vegas climate is extremely dry with very low humidity. Secondly, the cooltower can be used for stack ventilation during the more moderate spring and fall months. Finally, the cooltower would be a visual cue for the center for those driving on the adjacent highway, as well as a monument celebrating passive cooling techniques.
32
COOLTOWER (CONT.) Summer DB = 106°F Mean Coincident WB = 65°F 106°F - 65°F = 41°F Exit Air Temp = 69°F Desired indoor temp = 82°F ∆t = 82 - 69 = 13°F This cooltower is able to account for 90% of the building’s cooling demands.
Air Supply Amount: Btu/hr = 54,523 cfm = (Btu/h) / (1.1)(∆t) cfm = (54,523 Btu/h) / (1.1)(13°F) = 3,813 cfm Tower: 40ft. Wet Pad Area: 32 ft2 Flow Rate = 3,400cfm
East Concept Elevation
MEEB Figure 8.20
North Concept Elevation 33
• ROOF POND A less water-intensive cooling strategy is a roof pond. The existing transit center design has a curved roof structure intended to orient the building and passengers towards the bus loading area. A small portion of the existing roof is flat, over the offices at the northwest corner. The roof pond requires a design change here. The entire roof west of the transit station would be converted to a flat structure. Summer DB = 106°F MDR = 30 Min Night Temperature = 106 - 30 = 76°F Pond ∆t = 85 - 76 = 9°F Pond Storage Capacity = .7(9°)(.5ft)(62.5lb/ft3)(1btu/lb °F) = 197 Btu/day ft2 Pond Size: (31.7 Btu/h ft2 x 18 h/day) / 197 Btu/day ft2 = 2.9 ft2/ft2 A required pond size of 2.9 ft2 for every square foot of floor area is not possible. One option is to consider the roof pond as a strategy to help bring the cooling load down and help account for the ten percent which the cooltower is not able to handle. If 2.9 ft2/ft2 is required to cool the entire building, than ten percent of that is .29 ft2/ft2 which is realistic, and could fit above the western roof. This leaves the character of the curved roof over the primary transit area intact. However, the practicality of investing in a roof pond that only accounts for ten percent of the cooling load seems unreasonable.
• FINDINGS The extremes of the Las Vegas climate present challenges for passively cooling a building, particularly one with the high occupancy volume of a transit center. Of the strategies explored, the cooltower proved to be the most effective. As discussed, this has a dependence on water, which is a trade-off. However, the tower can also be utilized for stack effect during the more moderate months of spring and fall, warranting the investment. Additionally, water saving features could be pushed very heavily elsewhere on site to help balance the increase in water consumption by the cooltower. With the cooltower accounting for 90% of the summer cooling, the remaining 10% could be handled by a small air conditioning unit during hot months. 34
Phase 6 Solar Savings Fraction in Detail Calculate LCR and SSF BLC = 12,200 Btu/DD Ap = 332 ft2 LCR = 12,200 BLC / 332 ft2 collector area = 36.8 SSF = 71% Compare Design Guideline SSF with Calculated SSF The actual SSF of .71 is inbetween the low and high (.58 and .79) estimates given in the design guideline. In this case, the design guideline provided a good starting point for passive solar design.
s
a Veg Las
egas Las V
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Find the interior temperature swing on a clear January day. Avg January ambient temperature TA = 44F°
∆t = 23F° ∆t Int. = Total Int. Gains (Pple + Equip + Elect Light Loads) BLC + (UAs x 24) ∆t internal = (13.3 + 1.0 Btu/h ft2) x 1,720 ft2 x 9 h/day 12,200 Btu/DD + (332 ft2 x 24) = 221,364 = 11F° 20,168 Avg January clear-day indoor temp = 44 + 23 + 11F° = 78F° Direct Gain: mass area / glass area = 1,720 ft2 / 332 ft2 = 5:1 Indoor temp swing = 0.55 x ∆t solar = .55 x 23F° = 12.6F° Therefore, the clear January day interior will vary between: 78F° + 12.6/2 = 84.3F° 78F° - 12.6/2 = 71.7F° Las Vegas receives a fair number of sunny days during the winter, so it is reasonable to expect the calculated ∆t to be experienced within the building. However, the internal heat gain due to the ‘assembly space’ categorization is a significant contributor to the average indoor temperature and the resulting high temperature of 84F°. Since the transit station only holds high volumes of people for a couple of hours each day in the morning, altering the design to reduce this high winter temperature for these couple hours at the expense of others seems inappropriate. Also, the building will not yet have reached this high temperature at the time of the morning peak use. When the building does reach higher temperatures, heat can be released through the cooling tower/stack vent or operable windows. 36
CONCLUSION Major challenges during this study were traditionally focused on two things, the battle of visibility versus overglazing, and the high internal loads created from the functioning use of a high-volume transit center in the hot climate of Las Vegas. The second cannot be controlled, but the first issue was addressed early and often. This exploration revealed the inappropriateness of the vast south glazing wall and the missed opportunity to incorporate solar in a more thoughtful way to help shade the building, produce electricity and still maintain the desired visual connections. From a cooling perspective, the building currently relies entirely on a traditional air conditioning unit. The redesign proposal to introduce a cooltower addresses this dependence, but creates a new attachment to water. With the reduction of water-use elsewhere on site and the dual function of the cooltower as a stack to help with natural ventilation, this move can be justified. This also creates a functional iconic element for those passing by on the adjacent interstate. Additional interventions such as the incorporation of a heat exchanger to reduce lung loss and introducing more operable windows for increased control over the building temperature help add to the major building alterations. Combined with the changes previously mentioned, these design proposals result in a dramatic reduction in the buildingâ&#x20AC;&#x2122;s dependence on a traditional mechanical system.
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