ENVIRONMENTAL ANALYSIS OF ARIEL ARENA ARCH 8730 ENVIRONMENTAL SYSTEMS I ALEX LIBENGOOD, JAMES MICHAEL BEVERIDGE, JARED LEE
Page 1 of 19
TABLE OF CONTENTS PROJECT DESCRIPTION
3
CLIMATE ANALYSIS
4
BUILDING DESIGN
5
BUILDING SECTIONS
6
ENVELOPE SYSTEMS
7
ELEVATIONS & MASS
8
ENERGY ANALYSIS - HEAT LOSS
9
ENERGY ANALYSIS - HEAT GAIN
10
HEAT EXCHANGE / SUMMARY OF PASSIVE SYSTEMS
11
ACTIVE HEATING & COOLING
12
SOLAR STRATEGIES
13
ELECTRICAL LOAD & PHOTOVOLTAIC CALCULATIONS
14 / 15
SYSTEM RELATIONSHIPS
16
LIGHT & SHADE
17
DAYLIGHTING ANALYSIS
18 / 19
ENERGY LOAD ANALYSIS
20 / 21
PARAMETRIC ANALYSIS
22
SUMMARY OF ACTIVE SYSTEMS / REFERENCES
23
Page 2 of 19
PROJECT DESCRIPTION
THE SITE
THIS PROJECT
MVNU is 45 minutes Northeast of Columbus, Ohio. The Arena site is located adjacent to the existing gym facilities and the recently renovated Student Union. The new arena is to be attached to the student union and serve as the new athletic and event headquarters while the existing gyms retain a supportive role as intramural gyms.
The purpose of this project is to design and analyze a building of over 10,000 square feet in a specific climate using passsive heating and cooling strategies to migitate environmental extremes and make the interior environment of the building comfortable as much as possible without relying on the central HVAC system. In the following pages, I will walk you through a previous project that I worked on in Central Ohio, and examine the various passive strategies employed to midigate not only long term functioning costs, but upfront construction/building costs for a client on a budget. We will look at the building envelope in detail as well as how each passive heating/cooling strategy contributes to the efficiency of the project. Finally, considering these strategies, we will do the heat loss (winter), heat gain (summer), and heat exchange (radiation) of the building to examine how well these strategies are potentially working.
Mount Vernon
Student Union/ Gym
Campus
Site
THE CLIENT Mount Vernon Nazarene University (MVNU) started as a small community college in 1968, and has since found it’s feet as a growing private liberal arts university with burgeoning programs including nursing, politics, and religious studies. This growth has brought a steady increase in the student population, and with it the invested interest in conference-level athletics. For 15 years, the school has talked about and planned for a new athletic arena, and in 2008, a major donor surfaced that finally made a new facility a possibility.
N To preserve the new baseball fields on the North,the Arena Addition will be attached to the South side of the existing Student Union. This will give the Arena adequate frontage for campus life, and keep the new parking on the back (East ) side of the site.
THE PURPOSE The current athletic gym resides in two attached pre-engineered metal buildings, one an addition to the other - both unconditioned and unsuitable for NCAA level competition. MVNU’s apart from the grass fields and a ball pit, the soccer , golf, and baseball prorgrams have no facilities except for the coaches offices in adjacent to the gym. The new facility needs to house indoor basketball, and volleyball courts setup for NCAA competition tournaments. It will also incllude dedicated office wing for all athletics, home and visitor locker rooms, a physical training and rehab center, seperate team weight room and student fitness center, event space and additional classrooms.
LOWER LEVEL
UPPER LEVEL
THE PROGRAM
The site slopes down from the South side of the existing Student Union and gym facility. The new building will be a split level, raising 8 feet to the upper level, and lowering 6 feet to the lower level. The existing building will be flanked on the entire South side by a new lobby and event space that will act as the connector between the old and new buildings. The gym will be “stadium style” with the public space on the upper level and accessing the gym seating from the top-down. The offices are tucked under the banquet hall on the East side of the gym, and the student fitness center stacked on top of the team weight room. Page 3 of 19
CL IMATE A N A LYS IS
COMFORT - 11.9% (1,043 HRS)
According to ASHRAE Standards, with users wearing appropriate season clothing, the building should be comfortable without either active or passive heating and cooling strategies
SUN SHADE WINDOWS -
8.8% (767 HRS)
The Arena will have sun shades on all East and West windows, thus reducing unwanted heat gain during hot hours. The South facing windows have overhangs to block the summer sun and allow winter sun.
HIGH THERMAL MASS + FLUSH - 5.4% (471 HRS)
The majority of the exterior walls are masonry, creating high thermal mass to soak up heat energy and effectively limit the temperature swings of the day. The HVAC will also bring in cool night air in hot months.
INTERNAL HEAT GAIN - 24.1% (2,114 HRS)
Since this is a high-activity center meant to be open long hours with lots of people, bright lighting, electrical workout equipment, and kitchens the internal heat gain will help keep the building warm during cold months.
SOLAR DIRECT GAIN - 5.8% (512 HRS)
Large windows on the South facade are faced opposite by big masonry walls that act as a trombe during winter months, collecting and storing heat energy during the day, and releasing it throughout the night.
FORCED VENTILATION COOLING - 7.5% (655 HRS) Large fans can be installed in the gym and workout areas to move the air and make the space feel cooler. Combined, these passive temperature control strategies make the building “comfortable� for 33.6% of the year, for a
45.5% total time where potentially no active systems are required based on environment alone.
The dots on this psycometric CHART each represent an hour during the year plotted in respect to temperature and humidity. GREEN DOTS represent hours that fall into the comfort zones provided by the passive systems described above. The RED DOTS represent all the hours that the mechanical systems (active heating, cooling, and humidifaction) will have to work to bring the building within acceptable comfort ranges.
PSYCOMETRIC CHART FOR COLUMBUS, OHIO Page 4 of 19
BUILDING DESIGN
A high clerestory runs the entir length of the lobby, washing the entire public event space with natural Northern light without contributing to unwanted heat gain.
LOWER LEVEL FLOOR PLAN NORTHWEST PERSPECTIVE These windows are West-facing and have shades with a astronomical clock that lowers them according to the anle of the sun. This reduces heat gain, and keeps glare off of the gym floor
Number of Floors - 2 (Split Level) Total Square Feet - 67,000 sf Building Height - 40’
This 331 sf portion of the floor is cantilevered and open underneith
These large windows on the Southern corners of the Arena have overhangs that help keep summer sun out, and let winter sun in. They also are backed by large masonry walls on the inside that act as tromb walls and keep glare off of the courts.
SOUTHWEST PERSPECTIVE The Eastern-facing windows serve the Banquet Hall and Office space. Each window has manual pulldown shades so that the occupants can choose the amount of natural light they receive. The windows are kept small to prevent heat gain in the morning.
N
IO
CT
SE
UPPER LEVEL FLOOR PLAN
A
SECTION B
SECTION C
The building is constructed mostly from high-mass materials like brick, CMU, and fiber cement board which have high heat capacity and help reduce the daily temperature swings.
SOUTHEAST PERSPECTIVE Page 5 of 19
73 °
SUMMER SOLSTICE
BUILDING SECTIONS WINDOW OVERHANG
Overhangs on the Southern facade fenestration block direct sunlight from getting into the building, reducing heat gain in the summer, while allowing heat transmission from the sun into the spaces during the winter months when the sun is low on the horizon, and heat gain is desireable to help keep the building warm.
HIGH THERMAL MASS CONSTRUCTION
The the high mass of the masonry construction of the exterior walls helps midigate the temperature swings of the summer days, soaking up high amounts of heat energy from the sun that would otherwise heat up the interior of the building, and releasing it at night when it cools off.
SUN SHADE WINDOWS
Shades on the Western facade windows are connected to a automated astronomical clock that lowers the shades only as much as needed to keep out direct sunlight. The shades themselves are dark in color and translucent, letting 5% of the light through so that the view out of the window is never completely blocked. These shades reduce heat gain from direct sunlight transmission, while at the same time reducing glare on the gym floor.
hall
26 °
SECTION A
TROMBE WALL
During the winter months, the masonry trombe wall soaks up heat energy from the sun during the day, and at night radiates that energy back into the building environment, helping to reduce the necessary heating during the winter nights.
SECTION A
WINTER NIGHTS
storage
SOLAR DIRECT GAIN
TROMBE WALL
WINTER SOLSTICE
SECTION A
COOLING PASSIVE VENTILATION
The HVAC supply duct is low on the gym floor, and the return is high in the ceiling, allowing the passive ventilation of hot air rising to provide circulation in the Arena.
FORCED VENTILATION
gym
SECTION B
When passive ventilation can’t compensate for the internal heat gain, large ceiling fans in the gym provide forced ventilation cooling just by moving air in the alrge space, making it feel cooler and thus more comfortable during heavy activity.
ACTIVE FLUSH
During the summer nights when the air outside is cooler and less humid, the HVAC system opens up and flushes the gym with night air, then closes up in the morning to trap the cool air inside.
SECTION C Page 6 of 19
ENVELOPE SYSTEMS Formulas:
0.82 3/4” 1.093 0.95 0.2 1 1/2” 0.13 7.5 - 8mm 16.7 0.06 - 6” 0.053 19 5[1] 3 5/8” 1.38 0.725 - 2” 0.99 1.01 - 5/8” 1.78 0.56 - 5/8” 1.78 0.56 456[1] 1” 456 0.002[3] - 8” 0.90 4.55[5] - - 0.74 1.35[6] - - 6.00 0.17[6] - - 4.00 0.25[6]
Air Space Conductance Calculation:[2] C(x) =
The U.S. Department of Energy recommends and R-value of 13-15 for the walls in residential consrtuction, but no recommendation for commercial[9]
((4"-2")0.99+(2"-3/4")0.99) (4"-3/4")
=
0.99
2” Air Space
1 1/2” Rigid Insulation
1 1/2” Rigid Insulation
8mm Weather Barrier 5/8” Densglass 6” Metal Stud Batt Insulation 5/8” Gypsum Board
WALL 1A
Fiber Cement Board: Rigid Insulation: Weather Barrier: Densglass: Batt Insulation: Gypsum Board: Inside Air Layer:
Batt Insulation
29.98
Batt Insulation
WALL 2A
Brick: Rigid Insulation: Air Space: Weather Barrier: Densglass: Batt Insulation: Gypsum Board: Inside Air Layer:
TOTAL R-VALUE:
0.725 7.5 1.01 0.06 0.56 19 0.56 1.35
Metal Siding: Rigid Insulation: Weather Barrier: Densglass: Batt Insulation: Gypsum Board: Inside Air Layer:
8” Foam-Filled CMU
WALL 1B
Fiber Cement Board: Rigid Insulation: Weather Barrier: Foam-Filled CMU: Inside Air Layer:
0.95 7.5 0.06 4.55 1.35
TOTAL R-VALUE: 14.41
TOTAL R-VALUE:
30.77
0.002 7.5 0.06 0.56 19 0.56 1.35
29.03
Ribbed Metal Siding
2” Air Space
8mm Weather Barrier
5/8” Gypsum Board
WALL 3A
Brick
1 1/2” Rigid Insulation
6” Metal Stud
8mm Weather Barrier
1 1/2” Rigid Insulation
INTERIOR
NOTE - Unless noted otherwise, all values are sourced from : Mechanical and Electrical Equipment for Buildings, B. Stein and J. S. Reynolds, 9th Ed., Wiley, 2000
5/8” Densglass
6” Metal Stud
8” Foam-Filled CMU
8mm Weather Barrier 8” Foam-Filled CMU
WALL 2B
Brick: Rigid Insulation: Air Space: Weather Barrier: Foam-Filled CMU: Inside Air Layer:
TOTAL R-VALUE:
0.725 7.5 1.01 0.06 4.55 1.35
INTERIOR
3.52
Including the inside air space, the total R-value of the glazing is . Since the outside air layer is dependent on the season (or temperature), the outside air layer will be calculated on a per instance basis.
0.95 7.5 0.06 0.56 19 0.56 1.35
3/4” Fiber Cement Board
THE GLAZING
All windows are double-paned, low emmissivity (Low-E) glass with 1/2” argon filled air space. The frames are aluminum with a thermal break. The U-value for this glazing is 0.46, giving the windows an R-Value of 2.17.
5/8” Densglass
5/8” Gypsum Board
INTERIOR
There are three wall exterior wall types on this building, each with two different structures making 6 different wall conditions total. Where the walls are on the lower level, each of the three wall types has a 8” CMU structure (with exception to the walls around the offices where a higher R-value was necessary). Once the walls reach the upper level, they all transition to 6” metal stud structure to increase the R-value for the occupied spaces, incorporate a higher finish level, and to accomodate additional built-in wiring and light fixtures. This puts the exposed CMU in the unoccupied support spaces, where finish and comfort are less of a priority. Since the upper level and the office spaces are the most highly occupied spaces, this allows us to place the insulation where it has the highest value.
8mm Weather Barrier
8mm Weather Barrier
TOTAL R-VALUE:
THE WALLS
1 1/2” Rigid Insulation
INTERIOR
Conductance (C) Resistance (R)
Ribbed Metal Siding
Brick
INTERIOR
3/4” Fiber Cement Board: 1 1/2” Rigid Insulation Board: Weather Barrier: 6” Batt Insulation: Brick (Common): 2” Air Space[2]: 5/8” Densglass Sheathing: 5/8” Gypsum Board: Ribbed Metal Siding: 8” Foam-Filled CMU (105 PCF): Inside Air Layer: Outside Air Layer (Winter): Outside Air Layer (Summer):
Conductivity (k) Thickness (x)
3/4” Fiber Cement Board
INTERIOR
WALL MATERIALS
C = k/x R = 1/C
NOTE - Metal studs have a minimal profile, thus thermal bridging is minimal, and the R-value of these walls are calculated is if they were uniform. The R-value of the outside air layer is also not calculated here because it is dependent on the season, and will be calculated on a per-instance basis.
15.2
WALL 3B
Metal Siding: Weather Barrier: Foam-Fileld CMU: Inside Air Layer:
TOTAL R-VALUE:
0.002 0.06 4.55 1.35
5.96
This wall has the lowest R-value because it is for the unoccupied emergency stair tower.
Page 7 of 19
ELEVATIONS & MASS These elevations are facing Southeast 1338sf
96sf 510sf
805sf
340sf
2779sf
513sf
638sf
57sf x 6
126sf
215sf
335sf
415sf
42sf
291sf
12.5sf x 16
ROOF MATERIALS EPDM Rubber Membrane: 6” Rigid Insulation Board: Metal Deck: Inside Air Layer: Ouside Air Layer (Winter): Ouside Air Layer (Summer): EPDM Rubber Membrane
These elevations are facing Southwest 307sf x 5
WALL 3A: 1,271 SF WALL 3B: 42 SF
686sf
398sf
513sf
370sf
285sf
1063sf
177sf
1063sf
589sf
532sf
WALL 2A: 1,442 SF WALL 2B: 2,125 SF
410sf 140 sf
90 sf 87 sf
31.15
Roof Structure Below
For this Zone-5 climate, ASHREA 2010 recommends a minimum roof deck insulation of 30 [8]
Formulas: C = k/x R = 1/C
12.5sf x 3
40 sf
WALL 3A: 1,571 SF GLAZING: 164.5 SF WALL 3B: 589 SF SOUTH ELEVATION
1130sf 267sf
1 1/2” Metal Deck
1442sf
These elevations are facing Southwest 185sf
ROOF R-VALUE:
436 sf
270 sf
305sf
WALL 1A: 686 SF WALL 1B: 2,126 SF
EAST ELEVATION
These elevations are facing Southeast
175sf
267 sf
GLAZING: 1,686 SF
- 30mm 20 0.05[4] 0.2 6” 0.033 30 456 1” 456 0.002[3] - - 0.91 1.10[6] - - 6.00 0.17[6] - - 4.00 0.25[6]
EXTERIOR
6” Rigid Insulation
WALL 1A: 1,434 SF WALL 2A: 3,292 SF WALL 1B: 510SF WALL 2B: 750 SF
Conductivity (k) Thickness (x) Conductance (C) Resistance (R)
96sf
152sf 49sf
220sf
178sf
220sf
178sf
220sf
178sf
220sf
178sf
220sf
43sf
156sf
375sf
230sf
255sf
317sf
145sf
317sf
145sf
317sf
145sf
317sf
145sf
317sf
215sf
555sf
FLOOR MATERIALS Conductivity (k) 4” Concrete Slab: 13” Air Space[2]: 8” Batt Insulation: 5/8” Densglass: Weather Barrier: 1 1/2” Rigid Insulation: 3/4” Fiber Cement Board: Inside Air Layer: Outside Air Layer (Winter): Outside Air Layer (Summer):
Thickness (x)
Conductance (C) Resistance (R)
12[1] 4” 3.00 1/3 - 13” 1.45 0.69 - 8” 0.033 30 - 5/8” 1.78 0.56 - 8mm 16.7 0.06 0.2 1 1/2” 0.13 7.5 0.82 3/4” 1.093 0.95 - - 0.37 2.70[6] - - 6.00 0.17[6] - - 4.00 0.25[6]
4” Concrete Slab
WALL 1A: 1,378 SF WALL 1B: 555 SF
WALL 2A: 0 SF WALL 2B: 2,055 SF
WALL 3A: 1,364 SF GLAZING: 1,753 SF WALL 3B: 617 SF WEST ELEVATION
13” Air Space 8” Batt Insulation 5/8” Densglass
925sf 1207sf 978sf 269sf
WALL 1A: 925 SF WALL 1B: 0 SF
307sf x 5
910sf EXISTING BUILDING 3060sf
WALL 2A: 910 SF WALL 2B: 1,804 SF
WALL 3A: 1,207 SF WALL 3B: 26 SF
62sf 26sf
GLAZING: 1,040 SF
NORTH ELEVATION
8mm Weather Membrane 1 1/2” Rigid Insulation 5/8” Fiber Cement Board
Air Space Conductance Calculation:** C(x) = ((4"-13")0.81+(13"-3/4")0.98) = (4"-3/4")
1.45076923076
FLOOR R-VALUE:
42.79
EXTERIORNOTE - Unless noted otherwise, all values are sourced from :
Mechanical and Electrical Equipment for Buildings, B. Stein and J. S. Reynolds, 9th Ed., Wiley, 2000 NOTE - The R-value of the outside air layer is not calculated here because it is dependent on the season, and will be calculated on a per-instance basis.
Page 8 of 19
ENERGY ANALYSIS HEAT LOSS
Design Conditions: Location: Season: Outside Air Layer R-Value: Outdoor Design Temperature: Indoor Design Temperature: Edge Insulation Factor (F):
East Elevation
South Elevation
West Elevation
North Elevation
THE CONDITIONS
40.39 deg N Latitude Winter 0.17
Since the average temperature of this building’s climate is below “comfortable” temperatures for the majority of the year, we will start by calculating the heat loss of the building on a cold winter day.
-5
F
70
F Slab edges are insulated with continuous 1 1/2" rigid insulation board around the edges and within 4' of the slab edge.
0.2
Conduction (Walls/Roof)
Area (ft^2)
Wall 1A Wall 1B Wall 2A Wall 2B Wall 3A Wall 3B Glazing
1,434 510 3,292 750 1,271 42 1,686
29.98 14.41 30.77 15.2 29.03 5.96 3.52
30.15 14.58 30.94 15.37 29.2 6.13 3.69
0.033 0.069 0.032 0.065 0.034 0.163 0.27
75 75 75 75 75 75 75
3,549 2,639 7,901 3,656 3,241 513 34,142
Btu/h Btu/h Btu/h Btu/h Btu/h Btu/h Btu/h
Wall 1A Wall 1B Wall 2A Wall 2B Wall 3A Wall 3B Glazing
686 2,126 1,442 2,125 1,571 589 164.5
29.98 14.41 30.77 15.2 29.03 5.96 3.52
30.15 14.58 30.94 15.37 29.2 6.13 3.69
0.033 0.069 0.032 0.065 0.034 0.163 0.27
75 75 75 75 75 75 75
1,698 11,002 3,461 10,359 4,006 7,201 3,331
Btu/h Btu/h Btu/h Btu/h Btu/h Btu/h Btu/h
Wall 1A Wall 1B Wall 2A Wall 2B Wall 3A Wall 3B Glazing
1,378 555 0 2,055 1,364 617 1,753
29.98 14.41 30.77 15.2 29.03 5.96 3.52
30.15 14.58 30.94 15.37 29.2 6.13 3.69
0.033 0.069 0.032 0.065 0.034 0.163 0.27
75 75 75 75 75 75 75
3,411 2,872 0 10,018 3,478 7,543 35,498
Btu/h Btu/h Btu/h Btu/h Btu/h Btu/h Btu/h
Wall 1A Wall 1B Wall 2A Wall 2B Wall 3A Wall 3B Glazing
925 0 910 1,804 1,207 26 1,040
29.98 14.41 30.77 15.2 29.03 5.96 3.52
30.15 14.58 30.94 15.37 29.2 6.13 3.69
0.033 0.069 0.032 0.065 0.034 0.163 0.27
75 75 75 75 75 75 75
2,289 0 2,184 8,795 3,078 318 21,060
Btu/h Btu/h Btu/h Btu/h Btu/h Btu/h Btu/h
45,933
31.15
31.32
0.032
75
110,239 Btu/h
331
42.79
42.96
0.023
75
571 Btu/h
Cantilevered Floor Floor Loss Through
Edge Insulation
2,055 1,364 617 1,753
15.2 29.03 5.96 3.52
15.37 29.2 6.13 3.69
0.065 0.034 0.163 0.27
75 75 75 75
10,018 3,478 7,543 35,498
Btu/h Btu/h Btu/h Btu/h
Wall 1A Wall 1B Wall 2A Wall 2B Wall 3A Wall 3B Glazing
925 0 910 1,804 1,207 26 1,040
29.98 14.41 30.77 15.2 29.03 5.96 3.52
30.15 14.58 30.94 15.37 29.2 6.13 3.69
0.033 0.069 0.032 0.065 0.034 0.163 0.27
75 75 75 75 75 75 75
2,289 0 2,184 8,795 3,078 318 21,060
Btu/h Btu/h Btu/h Btu/h Btu/h Btu/h Btu/h
45,933
31.15
31.32
0.032
75
110,239 Btu/h
331
42.79
42.96
0.023
75
571 Btu/h
Perimeter ft (P) 998
(Ti - To) 75
Roof Roof Cantilevered Floor Floor
Edge Loss Through Insulation Edges Factor (F) He = F*P(Ti-To) 0.2
Loss Through Slab Hs=F*A
Total RValue System R- (+Outside Value Air Layer)
Roof Roof
North Elevation
Wall 2B Wall 3A Wall 3B Glazing
U-Value
(Ti - To)
Heat Loss H=AU (Ti-To)
(Lecture 7, Slide 6)
Conduction Loss Factor (F) 2
Loss Through Window Cracks Hi=0.018Q(TiTo)
Heat Loss (Lecture 7, He=F*P(Ti-To) Slide 6) 14,970 Btu/h
Area in Contact With Soil (A) 41,625 Infiltration Airflow Volume (Q) 20 ft^3/h
Heat Loss Hs=F*A
(Ti - To)
(Lecture 7, Slide 6) 83,250 Btu/h
Heat Loss Hi=0. 018Q(Ti-To)
75
(Lecture 7, Slide 6)
27 Btu/h
Total Heat Loss (H.L.) = sum(Hc+He+Hi+Hs) 406,300 Btu/h =
CONCLUSIONS
During an extreme winter conditions , this building is estimated to loss 406,300 Btu per hour. The roof is the largest factor in that it is contributing to 27% of the total heat loss. With an R-value of 30, the roof falls within the recommended range of insulation, but due to it’s large area, and the fact that the walls are almost just as well insulated, it’s piece fo the pie is inflated. The glazing is right behind the roof, contributing as much as 23% of the heat loss, when they only make up 4% of the total building surfaces (including the floor slab). This is because the U-value of the windows is so low. The next biggest contributor to the total heat loss if the floor slab at 20%. There isn’t much that can be done about this other than adding insulation below the floor which is highly cost prohibitive. The walls themselves only contribute 17% to total heat gain, when they are 22% of the total surfaces, meaning the walls are well insulated and pulling their weight. Overall, when considering the size of this building, the total heat loss is not significant, and the building is well-designed for this cold weather climate. On average, the building is losing 3.4 Btu per hour per square foot, which is fairly small.
Page 9 of 19 Perimeter
Heat Loss
(Lecture 7,
Roof Roof
ENERGY ANALYSIS HEAT GAIN
Location: Season: Outside Air Layer R-Value: Outdoor Design Temperature: Indoor Design Temperature:
40.39 deg N Latitude Summer
South Elevation
West Elevation
North Elevation
Next we will look at the building performance on a hot summer day to compare the amount of heat transfer in hot vs. cold conditions.
0.25 90 F 75 F
Conduction (Walls/Roof)
Area (ft^2)
Total RValue System R- (+Outside Value Air Layer)
Wall 1A Wall 1B Wall 2A Wall 2B Wall 3A Wall 3B
1,434 510 3,292 750 1,271 42
29.98 14.41 30.77 15.2 29.03 5.96
Wall 1A Wall 1B Wall 2A Wall 2B Wall 3A Wall 3B
686 2,126 1,442 2,125 1,571 589
Wall 1A Wall 1B Wall 2A Wall 2B Wall 3A Wall 3B Wall 1A Wall 1B Wall 2A Wall 2B Wall 3A Wall 3B
Roof Roof Cantilevered Floor Floor
Conduction (Glass)
East Elevation South Elevation West Elevation North Elevation
Conduction (Glass) Glazing Glazing Glazing Glazing
East Elevation South Elevation West Elevation North Elevation
Radiation (Glass) Glazing Glazing Glazing Glazing
THE CONDITIONS
Determine heat gain at 4pm on June 21st
East Elevation
Cantilevered Floor Floor
U-Value
ETD (Lecture Heat Gain H=AU 7, Slide 13) (ETD)
(Lecture 7, Slide 10)
30.23 14.66 31.02 15.45 29.28 6.21
0.033 0.068 0.032 0.065 0.034 0.161
19 18 24 30 24 30
899.118 624.24 2,528.256 1,462.5 1,037.136 202.86
Btu/h Btu/h Btu/h Btu/h Btu/h Btu/h
29.98 14.41 30.77 15.2 29.03 5.96
30.23 14.66 31.02 15.45 29.28 6.21
0.033 0.068 0.032 0.065 0.034 0.161
25 13 38 21 38 21
565.95 1,879.384 1,753.472 2,900.625 2,029.732 1,991.409
Btu/h Btu/h Btu/h Btu/h Btu/h Btu/h
1,378 555 0 2,055 1,364 617
29.98 14.41 30.77 15.2 29.03 5.96
30.23 14.66 31.02 15.45 29.28 6.21
0.033 0.068 0.032 0.065 0.034 0.161
32 11 51 16 51 16
1,455.168 415.14 0 2,137.2 2,365.176 1,589.392
Btu/h Btu/h Btu/h Btu/h Btu/h Btu/h
925 0 910 1,804 1,207 26
29.98 14.41 30.77 15.2 29.03 5.96
30.23 14.66 31.02 15.45 29.28 6.21
0.033 0.068 0.032 0.065 0.034 0.161
18 9 23 13 23 13
549.45 0 669.76 1,524.38 943.874 54.418
Btu/h Btu/h Btu/h Btu/h Btu/h Btu/h
45,933
31.15
31.4 0.032
19
331
42.79
43.04 0.023
Area (ft^2)
Total RValue System R- (+Outside Value Air Layer)
U-Value
27,927.264 Btu/h
20 152.26 Btu/h ^ No ETD provided for overhanging floors assuming a cantilevered floor ETD is half of that of a roof since it receives no sun.
(To - Ti)
Heat Gain Hc=AU (Lecture 7, (To-Ti) Slide 10)
Lighting Emission Factor (F) = Consumed Energy (W) =
Occupants
45,933
31.15
31.4 0.032
331
42.79
43.04 0.023
Area (ft^2) 1,686 164.5 1,753 1,040
Total RValue System R- (+Outside Value Air Layer) 3.52 3.77 3.52 3.77 3.52 3.77 3.52 3.77
Area (ft^2) 1,686 164.5 1,753 1,040
Solar Heat Gain (Sg) 13 15 115 15
Shading Coefficient (S.C.) 0.6 0.25 0.6 0.25
U-Value 0.265 0.265 0.265 0.265 (Lecture 7, Slide 10) (curtains) (overhang) (curtains) (overhang)
(Radiation and Convection) 4.3 100,000 Watts (Radiation and Convection)
Heat Gain (H)
# of people (P)=
1,000
245
# of people (P)=
80
580
19
27,927.264 Btu/h
20 152.26 Btu/h ^ No ETD provided for overhanging floors assuming a cantilevered floor ETD is half of that of a roof since it receives no sun.
(To - Ti) 15 15 15 15
Heat Gain Hc=AU (To-Ti) 6,701.85 653.89 6,968.18 4,134
(Lecture 7, Slide 10) Btu/h Btu/h Btu/h Btu/h
Heat Gain Ho=A*Sg*S.C. 13,150.8 616.875 120,957 3,900
(Lecture 7, Slide 10) Btu/h Btu/h Btu/h Btu/h
Heat Gain Hm=F*W
(Lecture 7, Slide 10)
430,000 Btu/h << Huge energy consumption due to gym lighting and workout equipment
Btu/h at rest Btu/h physical activity
The Arena seats 2,000 people. This scenario accounts for the stands being half full, with 30 people on the court, and 50 people in the fitness and weight rooms
Heat Gain Hp=P*H
(Lecture 7, Slide 10)
245,000 Btu/h 46,400 Btu/h Total Heat Gain (H.G.) = sum(H+Hc+Ho+Hm+Hp) 936,816.759 Btu/h =
CONCLUSIONS
Considering all the passive cooling strategies employed, this author and designer was very surprised at the amount of heat gain this building is receiving. Upon closer review however, it can be noted that the people occupying the building on a normal sporting activity day contributes to 31% of the total heat gain. Lighting and equipment alone also contributes up to 46% of the heat gain. These two numbers are so high because of the nature of the Arena being a place for assembly and physical activity that requires bright lights and a good amount of workout equipment. Between radiation and conduction, the glazing accounts for only 16% of the total heat gain, meaning that the passive solar strategies are doing a comparatively fine job at midigating solar heat gain.
Finally, both the walls and the roof are doing an excellent job at keeping heat out of the building with both contributing to only 3% of the total heat gain. Overall, itâ&#x20AC;&#x2122;s a warm building in the summer that will need a good HVAC system to support the activities. However, these same activities will help keep the building warm in this cooler climate, especially since it will be occupied mostly during the colder months when school is in session. The night flushing of the air, the high thermal mass construction, the solar shades and overhangs, and the high R-values are keeping what could be an uncontrollable summer heat issue, a simply manageable one. Page 10 of 19
HEAT EXCHANGE RADIATION FROM ROOF
Stefan Boltzmann law: H = (5.67*10^-8)(e1*T1^4 – e2*T2^4) Area: 45,933 e1 = 0.8 T1 = 65 e2 = 1 T2 = 5 Convert Temperatures to Kelvin: T1 = 273 + (65-32)*5/9 = T2 = 273 + (5-32)*5/9 =
THE CONDITIONS
(Lecture 6 - Slide 13) ft^2
Finally, we look at heat exchange of the roof by radiation at night.
deg F deg F 291.333333333333 K 258 K
SUMMARY
OF PASSIVE SYSTEMS Mount Vernon Nazarene University has chosen to open a new chapter in their history by the opening of a new athletic facility that will not only support its burgeoning student population, but the surrounding community as well. As a result, the facility is expected to house thousands of visitors at once, posing a unique design challenge when it comes to managing comfortable interior environments without relying on overly massive HVAC systems. The designer is challenged with coming up with passive heating and cooling systems that are catered not only to the building environment, but moreso to the function of the activities it houses. This particular design employs multiple passive design strategies to help mitigate the environmental extremes of the relatively cold Ohio climate. These strategies include: • High thermal mass construction (heating & cooling) • Trombe walls (heating) • Window overhangs on Southern fenestration (cooling) • Sun shades on critical (Western) fenestration (cooling)
H = (5.67*10^-8)*(0.8*291.3^4-1*258^4) H= 75.53922664736 W/m^2 Convert from Watt to Btu/h (1 W = 3.41 Btu/h) and from square meter to square foot (1 m^2 = 10.76 ft^2): H = 75.54*3.41/10.76 Btu/h/ft^2 = 23.939 Btuh/ft^2 Entire Area: H(Total) = 23.939*45,933 = 1,099,590.09 Btuh
The design also includes multiple passive strategies to accomodate the active use of the building. These include: • Night flushing of the air (cooling) • Passive Ventilation (heating and cooling) • Forced Ventilation by ceiling fans (cooling)
CONCLUSIONS
While the building is gaining a lot of heat during periods of high activity during the day (not necessarily because of sun), the roof radiates even slightly more heat during the night. This is assuming that the building is able to keep the roof temperature at a constant 65 degrees F, but considering the 6” of insulation, it is unlikely that the roof surface will be able to maintain that temperature, and will likely fall more in the range of the actual outside temperature during the night.
These are all low cost strategies that are multipurpose and integral to the overall design of the building. This design will not only help keep the building comfortable, but they save money by reducing the size of HVAC system, and provide long term savings by reducing the energy needed to keep the space comfortable.
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ACTIVE HEATING / COOLING CONFIGURATION
Single mechanical room with interior heat pump equipment to manage the geothermal wells which would be sunken close to the facility.
AIR AND ENERGY DISTRIBUTION
The wells can be sunken in the surrounding lanscaped area in order to minimize distance from the structure and provide easy access.
The system used is a variable air-volume single-duct system. This will be beneficial for the efficiency of the building by supporting multiple temperature zones with individual control in each. This will be particularly useful due to the buildings wide range of functions (such as a storage room vs. a basketball court).
ACTIVE SYSTEMS We elected to use a geothermal system with closed-loop vertical ground heat exchangers tied into an indoor heat pump for both heating and cooling the building. The geothermal wells efficiently transfer free energy from the earth to the buildingâ&#x20AC;&#x2122;s heat pump, thereby reducing the amount of energy required by the active mechanical system to make the building comfortable on extreme climactic days. The vertical configuration was determined by the lack of space on the site that can be readily accessed in the event of need for maintenance on the system.
ENERGY RECOVERY
The building uses a heat recovery wheel in order to reclaim some lost heat from the mechanical room to heat water.
HUMIDITY
Reference 10
This climate typically has a high level of humidity so dehumidification will be necessary. We will use a dehumidifier as part of our mechanical system. Page 12 of 19
SOLAR STRATEGIES TYPE OF SOLAR COLLECTOR The project will have 3000 sq. ft. of solar collectors located on the roof of the gymnasium. We have chosen to use the AET-AE-Series collector to provide/ assist in hot water for the building. The system is designed with “crystal clear solar coating” which maximizes solar radiation absorption and performance. To maximize transfer rates the panel has efficient absorbers to allow the highest heat conduction through a system named “thermafin”. Each panel has a footprint of approx. 75sqft and the fluid capacity of 1.22 gallons. The system will be on a standard tilt mount system.
INTEGRATION WITH BUILDING
The solar collector system will provide/assist in hot water for the buildings two 80-gallon water boilers. With 40 solar collector units, approximately 48 gallons of water can be heated to assist these water boilers. The collector can either assist in initial heating of water or maintenance heating. The hot water boilers will deliver hot water to the many bathrooms, sinks, and showers throughout the building.
PHOTOVOLTAIC ROOFTOP SYSTEM
The project will have 15,000 sq. ft. of photovoltaic panels located on the roof of the gymnasium. These units will not only collect the suns heat for use as an active electrical power source, but also reduce cooling costs by blocking the suns heat and reducing thermal gain.
LOCATION, ORIENTATITION, TILT
The solar collectors are located on the rooftop of the gymnasium along with the photovoltaic system. The collectors are mounted with a standard mount and are (non-tracking). The panels are on a 37-degree tilt, and are facing due south at 40 degrees latitude for maximum sunlight. The system is also located closest to the boilers on the south face to reduce the amount of hot and cold water piping from the collectors to the boilers.
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ELECTRICAL LOAD & PHOTOVOLTAIC CALCULATIONS ELECTRICAL LOADS INTEGRATION WITH BUILDING
The PV panels will integrate with the building by helping to generate electrical power by converting solar radiation into DC electricity. The PV panels for this project are located on the main roof of the gymnasium. The solar units located on the roof will provide a passive cooling effect on the building during the day and also keep accumulated heat in the night while still contributing as an active system.
NETWORK INTEGRATION
The primary advantage for a photovoltaic as an active system is the reduction of energy cost. However the building is also has the potential to reduce the electrical load on the local power company, which helps reduce cost and waste.
LOAD CALCULATION AND SIZING
When calculating the electrical load for the MVNU, precedents pertaining to educational/athletic facilities helped to identify specific lighting quantities, exercise equipment, kitchen equipment, educational equipment, and technology loads. During the load calculation for the MVNU we also included normal commercial building loads pertaining to electrical and mechanical equipment.
After identifying potential load conditions for the MVNU our calculations revealed the building would have a daily average AC load of 3199.7 kWh/Day.
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ELECTRICAL LOAD & PHOTOVOLTAIC CALCULATIONS SOLAR PANEL CALCULATION STUDY
SOLAR PANEL SELECTION We have chosen the X-Series Solar Panel manufactured by Sun Power as our primary panel. The X21-345 panel has a 21.5% efficiency rating and is ideal for large roof spaces. This panel has the ability to generate 75% more energy per square foot than a conventional panel, with its ability to convert more sunlight to electricity over a 25-year period. The unit is designed with maxeon solar cells, which are designed for durability; they are impervious to the corrosion and cracking that degrades conventional panels and reduces efficiency. This panel was selected for its high efficiency rating and its ability to provide 265.12 kWh.
This study was completed to analyze which solar panels we could specify in order to achieve the maximum efficiency in terms of surface area.
PRECISE ESTIMATE CONCLUSION
In the calculation roughly 43,100 square feet of solar panels are required to meet the entire energy load for the building. However due to the surface area limitation, we are only able to allocate 15,000 sq. ft. of roof area on the gymnasium roof for photovoltaic use. The total power required by the building per sun hour at 4.2 hours per day for Ohio is 761.84 kWh and the PV panels will provide 265.12 kWh, which contributes approx. 35% of the buildings hourly consumption.
www.sunpowercorp.com/facts Page 15 of 19
SYSTEM RELATIONSHIPS COMPATIBILITY,CONFLICTS,COMPLEMENTARITIES
COST COMPARISON
AESTHETICS
SPACE REQUIREMENTS
There is very little difference between photovoltaic and solar thermal collector energy. PV panels could become more affordable in the future because they involve fewer mechanical parts than solar collectors and are scalable. As a continuous building system however PV panels combined with traditional electric water heaters have a lower initial cost, and are still using clean solar energy. The combination of solar thermal collectors and PV panels is an expensive operation that can theoretically allow the building to work off the grid. However, because this building is within a city and on a power grid the high cost investment in solar collectors and PV panels in the system do not outweigh other combinations currently. A geothermal system also has a high intial cost, but is by far the most efficient and should have a good return on investment due to the schools need to retain this building for a long time.
The PV and solar panels located on top of the gymnasium roof do not drastically affect the aesthetic of the building. The roofline of the building conceals the panels from most perspectives as a walking pedestrian, and they do not influence the architecture. However, ultimately the client and users primarily determine the panelâ&#x20AC;&#x2122;s aesthetic appeal. In our opinion the panels add an environmental / technological aesthetic to the building that promotes renewable energy.
The systems used in the project have a major limitation in how much surface area the photovoltaic and solar collectors occupy. Both systems are large and direction specific, which makes space a major limiting factor to the system. These systems can only be deployed outside - on the roof/ ground or windows, which have limited surface area. In some cases shading elements like trees and buildings must be removed or relocated to maximize sunlight over the panels to ensure efficiency and operation. The geothermal system is very space efficient as most of it is sunken into the ground with only a minimum of equipment needed in the mechanical room.
PHOTOVOLTAIC
GEOTHERMAL
SOLAR COLLECTOR
ADVANTAGES
DISADVANTAGES
ADVANTAGES
DISADVANTAGES
ADVANTAGES
DISADVANTAGES
1) Generates electricity using sunlight without emitting harmful greenhouse gas emissions
1) System is not consistent, solar intermittency issues like rain, clouds, and limited daylight reduce energy output
1) Renewable source of heating & cooling
1) Large initial financial investment compared to other heating systems
1) Renewable source of hot water generation by pre-heating water
1) Large initial financial investment compared to other heating systems
2) Low operating cost
2) Low operating cost
2) Additional equipment such as (DC to AC) converters and storage batteries increase initial investment cost
3) Low-maintenance
2) System cannot heat/cool to extreme levels
2) System is less efficient than PV panels in Cloudy weather and cannot function in diffused sunlight
2) Low operating and maintenance costs 3) Generates no noise, totally silent 4) Solar panels are promoted through government subsidy funding (FITâ&#x20AC;&#x2122;s, tax credits) 5) No mechanical moving parts
4) Able to minimize area within building dedicated to equipment
3) Requires exterior space for wells
3) Systems require large surface areas for deployment
3) Provides solar heating and cooling
3) Limited storage capacity for hot water 4) Does not produce electricity 5) Solar Collectors have moving parts including pumps and solenoid valves
4) Systems are fragile and can be damaged easily
SUMMARY
There are no actual functional compatibility conflicts between the active systems used with the building. However, due to a limited number of active systems based on usable surface area and overall output value it would be ideal to use all photovoltaic instead of solar collectors. The overall energy usability of the photovoltaic outweigh the hot water generation from the solar collectors. The PV panel system is lower cost and has the ability to generate electricity for a cheaper hot water system. The PV panel is more efficient than the solar collector with its capability to work most effectively in diffused light. The only conflict in the active system is the comparison between the value of the PV panel and the Solar Collector. In our investigation the PV panels advantages, usability, and value all outweigh the solar collector with a building on the grid. Page 16 of 19
LIGHT AND SHADE
SUMMER EQUINOX (JUNE 21ST)
2:00 pm At the hottest part of the day, the sun is high in the sky, and only comes into the gym a little bit.
5:00 pm As the summer sun starts to set, it reaches farther into the space, and falls onto the bleachers.
FALL & SPRING EQUINOX (SEPTEMBER/MARCH 21ST)
2:00 pm Since the sun altitude is lower than the summer months, the sun starts to come more into the space even in the early afternoon.
5:00 pm As the sun sets, it fully penetrates the gym, and will be causing glare on the court floor during games. Shades will be required until the sun sets.
WINTER EQUINOX (DECEMBER 21ST)
SHADING ANALYSIS
Using computer models, we are able to study the interior of the arena gym where the amount of direct sunlight coming into the space can be a big issue during sporting events. The main windows in the gym are on the western elevation, thus the gym only receives direct sunlight in the afternoon/ evening hours. Solar gain is the most intense during this time of day. These studies taken on each of the Summer, Fall, Winter, and Spring equinoxes at both 2:00pm when the sun is still high in the sky, and 5:00pm when the sun is low enough to really penetrate the space before it sets for the day. The spring and fall equinoxes are combined since the sun is theoretically in the same position in the sky during those times.
2:00 pm The altitude of the sun is now so low that it has a harder time coming into the gym in the early afternoon.
5:00 pm Now the sun altitude is so low, that it crosses almost horizontally across the gym and isnâ&#x20AC;&#x2122;t even able to touch the gym floor. Page 17 of 19
DAYLIGHTING ANALYSIS LIGHTING DESIGN
ATRIUM
The daylighting for this building was designed with particular intent. The client requested that the gym and lobby in particular be usable without having to keep the lights on. This way, when the university is giving tours of their new Arena, they wouldnâ&#x20AC;&#x2122;t have to warm up the large halogen lights, and the gym would be adequately lit for showing off during normal daytime hours when sporting events were not in progress. Most importantly, this would allow the university to save money not only in regards to electricity, but by reducing the internal heat gain, and thus the load being put on the mechanical systems. Therefore, this building was designed with plenty of large windows on all elevations to maximize the amount of daylight entering the building.
The atrium lobby doubles as an event space and gallery. The entire north elevation is flanked by a high clerestory window, filling this space with indirect northern light. The lobby is preceded by the tall glass entry on the West elevation, and terminated by the weight room on the East side with wide views of the site. These direct windows help make the lobby feel like it reach out onto campus and enhances the perceived spaciousness of the building while ensuring the lights only have to be turned on during the evening hours, or only 20% of the total time that the building is occupied. As a result, the lobby atrium receives on average 200 foot candles of light making it a perfect gallery.
ATRIUM LIGHTING RENDERINGS These renderings were done using Maxwell Render; a real-time photometric engine that calculates the way light actually reacts in a modeled space. This render shows how the clerestory floods the lobby with indirect northern light.
WITHOUT CLERESTORY
WITH CLERESTORY
WITH MATERIALS APPLIED
Even with windows at both ends, this space is kind of dark without artificial lighting.
The addition of the clerestory greatly improves the quality of the space without relying on active building systems.
Selection of materials is important when thinking about lighting a room. Materials of different reflectivity will change the way light bounces around in a space. In this study, the selected materials have slight reflectivity (semi-gloss wood ceiling, rubber floors, and semigloss painted walls) and thus bring the daylight deeper into the space. Page 18 of 19
DAYLIGHTING ANALYSIS GYMNASIUM
The Gym was much more difficult to design regarding the ownerâ&#x20AC;&#x2122;s daylighting request while also keeping glare off the court for sporting events. The solution was to place the stadium circulation all around the perimeter of the gym, letting these hallways take the brunt of the most intense daylight, averaging around 400 foot candles. These are not regularly occupied spaces, so the high amount of light would not be a big issue. The reflected light form these spaces then gets diffused into the gym. The large windows on the south side of the gym are flanked by the restrooms, blocking direct light from entering the gym. This space doubles as light diffuser and a trombe wall, thus offsetting the solar gain received from the southern sun. As a result, the gym receives an average of 150 foot candles, making it a well-lit space during the day without glare on the court and without having to rely on artificial lighting.
BANQUET HALL The Banquet Hall is designed to double as educational space, dividing into three separate classrooms via partition walls. The classrooms receive an average of 250 foot candles from the Eastern windows. This is a lot of light and ideal for focusing on detailed tasks, but not conducive for lectures and projectors. Therefore, these windows are equipped with dual-step 50% translucent and 100% blackout shades, allowing the occupants to control and reduce the amount of light coming in to these rooms.
GYMNASIUM RENDER STUDY
This study showed that the gym was receiving plenty of light, but the West windows were creating glare on the gym court, which is undesirable during sporting events. This showed us that shades are needed on these windows to reduce glare, but not cut out the light completely (see shade section diagram of windows).
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ENERGY LOAD ANALYSIS eQuest Yearly Energy Consumption
3D VIEW OF eQuest ANALYSIS MODEL
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ENERGY LOAD ANALYSIS eQuest Monthly Energy Consumption
HEAT GAIN June total energy consumption conversion from kWh/Month to Btu/hour: 87,000 kWh/Month * 3.42 * 1,000 = 297,540,000 Btu/Month * 1 month/30 days * 1 day/10 operating hours =
991,800 Btu/h
Compared to the Hand Calculation for heat gain on June 21st @ 4:00pm:
991,800 Btu/h
/ 966,395 Btu/h =
102.6%
The eQuest calculations had a 2.6% increase for the summer energy load analysis.
HEAT LOSS
The hand calculations only considered the amount of energy lost by the building by environmental conditions, and thus did not account for the energy required for the lighting, equipment, etc. Therefore, to do a realistic comparison, we have to subract the non-HVAC loads from the eQuest energy analysis for December: 103,800 kWh/Month (Total) – 55,300 kWh/Month (Lighting) = 48,500 kWh/Month December heating energy consumption conversion from kWh/Month to Btu/hour:
48,500 kWh/Month * 3.42 * 1,000 = 354,996,000 Btu/Month * 1 month/30 days * 1 day/13 operating hours
= 425,307 Btu/h Compared to the Hand Calculation for heat gain on June 21st @ 4:00pm:
425,307 Btu/h
/ 406,300 Btu/h =
104.7%
The eQuest calculations had a 4.7% increase for the winter energy load analysis
CONCLUSIONS
The energy transfers calculated by hand were surprisingly close to the energy load analysis computed by eQuest. However, certain assumptions we made that could significantly alter the accuracy of the report. For example, the hand calculations were done using specific environmental temperatures, whereas the eQuest analysis used avergae temperatures for that time of year. An unusual weather pattern can have a big effect on the energy transfer from a building to it’s environment and cause abnormal energy loads. Also the eQuest doesn’t indicate that it calculates the heat load contributed by people in the building and their amount of activity. This was a significant factor in this type of building as shown in the hand calculations. Furthermore, the heat loss hand calculations did not account for the continued heat gain from the people, lighting, and equipment. This forced us to subract the non-HVAC loads such as lighting from the eQuest analysis and hope this accounts for the difference. All these assumptions have the potential to invite significant margins in error. Ultimately this study shows the value of doing quick load analysis with computer modeling, while also highlighting the value of hand calculations when you need to consider conditions specific to your building design. Page 21 of 19
PARAMETRIC ANALYSIS
eQuest Monthly Energy Consumption
EQUEST PARAMETERS To evaluate the effects of various parameters on the energy load analysis, we change select variables to compare the changes in the total energy load. First, recognizing that this is a University, we changed the summer schedule by reducing the operating time by 4 hours in the evening. Next, we wanted to evaluate the effect of changing from double-pane windows to triple-pane windows to evaluate the cost effectiveness of this upgrade.
CONCLUSIONS Monthly Consumption Comparison Between Original (Orange) and Modified (Blue) Design Parameters
These two parametric values were ideal to compare the original building design to the original building design. The schedule change was less of a design parameter, and more of a programming parameter that the owner of the building has direct control over. By reducing the summer schedule by a mere 4 hours (40%) a day reduced the energy load in the summer by almost half! eQuest estimates this to be an energy reduction of 136,200 Btu/month with a savings of $16,344, or 13.1% per year. The second parameter that was changed was the type of glazing used throughout the building. By upgrading from double pane low-e windows to triple pane low-e windows, the energy load was reduced by about %1, or a savings of about $1,420 a year. With triple pane windows costing an avergage of 25-30% more than double pane windows, it could take 20 years or more to recoup the cost of this upgrade. Therefore, it would be wise to switch to triple pane windows only where the windows are on the South or West elevations, and the space is continually occupied, and therefore could be made uncomfortable by the heat gain from the afternoon sun. Page 22 of 19
SUMMARY
OF ACTIVE SYSTEMS The new athletic facility is a large structure and will be in constant use throughout the entire year, with the potential for a large number of users at any time. Additionally it will house a very wide range of spaces and uses. As such it will need a strong set of active systems to complement its passive strategies in order to create a comfortable space in addition to an efficient one. To take advantage of solar radiation, we have incorporated Photovoltaic Panels and Solar Collectors. To take advantage of ground-source heat we have used a Geothermal heating/cooling system. We have incorporated a Heat Wheel in order to re-capture energy. With these systems in place and taking advantage of the reduction in the base amount of energy required thanks to the passive strategies, Mount Vernon Nazarene University would be able to have an extremely efficient structure that could get the most out of both passive and active systems year-round.
REFERENCES
NOTE - Unless noted otherwise, all values are sourced from : Mechanical and Electrical Equipment for Buildings, B. Stein and J. S. Reynolds, 9th Ed., Wiley, 2000 [1] Conductivity value sourced from Lecture 4, Slides 18 & 19 [2] Air Space conductivity sourced from Lecture 4, Slide 12 & 13 [3] R-value sourced from http://archtoolbox.com/materials-systems/thermal-moisture-protection/24-rvalues.html [4] R-value sourced from http://www.radiantprofessionalsalliance.org/Pages/FloorCoveringR-ValueChart.aspx [5] R-value sourced as lightly reinforced from http://www.ncma.org/resources/Documents/2nd_ED_thermalCAT_FINAL.pdf [6] All Air space conductivity values sourced from Lecture 4, Slide 10 [7] Glazing U-values sourced from https://www.energyguide.com/info/window2.asp [8] http://www.greenzone.com/general.php?section_url=12 [9] http://www.applegateinsulation.com/Product-Info/Technical-Pages/249732.aspx [10] Diagrams sourced from http://www.coroflot.com/michaelschrader/engineering-componets [11] http://www.aetsolar.com/solar-thermal-collectors.php [12] http://www.geni.org/globalenergy/research/review-and-comparison-of-solar-technologies/Review-and-Comparison-ofDifferent-Solar-Technologies.pdf [13] http://www.greenbuildingadvisor.com/blogs/dept/musings/solar-thermal-dead [14] http://us.sunpower.com/small-medium-business/products-services/solar-panels [15] http://www.greentechmedia.com/
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