mit ocw cee 1-964 - design for sustainability - energy in buildings

7/27/2019 MIT OCW CEE 1-964 - Design for Sustainability - Energy in Buildings

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Buildings and Energy

Les NorfordBuilding Technology ProgramDepartment of ArchitectureMassachusetts Institute of Technology

CEE 1.964Design for SustainabilityNovember 1, 2006


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CEE 1.964Design for Sustainability

Outline

1. Buildings and energy some data

2. Residential buildings3. Commercial buildings4. Buildings in other (mainlydeveloping) countries5. Is current progress good enough?


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Global energy consumption

0.000

50.000

100.000

150.000

200.000

250.000

300.000

350.000

400.000

450.000

500.000

1 9 8 0

1 9 8 2

1 9 8 4

1 9 8 6

1 9 8 8

1 9 9 0

1 9 9 2

1 9 9 4

1 9 9 6

1 9 9 8

2 0 0 0

2 0 0 2

Year

E J

World Total

North America

Central/South America

Western Europe

Eastern Europe Former USSR

Middle East

Af rica Asia and Oceania

450 EJ = 14.3 TW


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CEE 1.964 Source: Goldemberg et al.

00.500

20

40

60

80

1000 40 80

Energy Consumption per Capita (MJ/Day)

120 160 200

1.00

Kilowatts per Capita

P h y s i c a

l Q u a

l i t y o

f L i f e

I n d e x

1.50 2.00 2.50

Agric Exporter

Primary Exporter

Oil Exporter Industrialized Countries

Balanced Economics

Other Agric

Design for Sustainability

Does energy use correlate with quality of life?

Figure by MIT OCW.


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U.S. energyend-use

Source:EIA

Electricity buildings 71%

Total energybuildings 39%

21%27%

Residential buildings

Commercial buildings

Transport

34%18%

Industry

Residential buildings

Commercial buildings

Transport

Industry

29%

35%

0%

36%

Figure by MIT OCW.

Figure by MIT OCW.


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U.S. residential and commercial buildingenergy use intensities

0.0

0.5

1.0

1.5

2.0

2.5

1975 1980 1985 1990 1995 2000 2005

year

E n e r g y u s e

i n t e n s

i t y ,

G J / m

2

residential primary

residential site

0

0.5

1

1.5

2

2.5

1975 1980 1985 1990 1995 2000 2005

year

E n e r g y u s e

i n t e n s

i t y , G

J / m

2

commercialprimarycommercial site

1 GJ/m 2 = 277 kWh/m 2

Apparently not a lot of progress in 25 years


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Residential buildings end-use energy 2003


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Commercial buildings end-use energy 2003


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2. Residential buildings: savings

potential in new construction30%: little or no increase in first cost50%: about the same life-cycle costNet-zero energy or carbon neutral: muchharderHow? INTEGRATED, SYSTEMS DESIGN

Better wallsBetter windowsSmaller HVAC equipmentBetter appliances

Savings relative to early 1990s benchmark


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Doing better with houses: lots of

insulation!

Flickr photo courtesy of Smalloy.


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Taking advantage of free heating

for elfhouse

-10

0

10

20

30

40

50

60

0 0 : 1

3 . 0

4 5 : 1

3 . 0

3 0 : 1

3 . 0

1 5 : 1

3 . 0

0 0 : 1

3 . 0

4 5 : 1

3 . 0

3 0 : 1

3 . 0

1 5 : 1

3 . 0

0 0 : 1

3 . 0

4 5 : 1

3 . 0

3 0 : 1

3 . 0

1 5 : 1

3 . 0

0 0 : 1

3 . 0

4 5 : 1

3 . 0

3 0 : 1

3 . 0

1 5 : 1

3 . 0

0 0 : 1

3 . 0

4 5 : 1

3 . 0

3 0 : 1

3 . 0

1 5 : 1

3 . 0

0 0 : 1

3 . 0

4 5 : 1

3 . 0

3 0 : 1

3 . 0

1 5 : 1

3 . 0

0 0 : 1

3 . 0

Time (hours)

T e m p e r a t u r e

( d e g r e e s

C )

Average Temperature First Week = 16.9 deg C Average Temperature Second Week = 17.3 deg C


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Insulation, glass and mass for a full-

size house

Walden made of 15 cm extruded polystyrene (noopenings, no airflow):~1,000 W of heat needed at 0oF.Henry David needs fresh air, which requires another500 W to heat.

image: Montgomery Co.Public Schools, VAwww.mcps.org


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Walden with south-facing, double-paneglazing and water for thermal storage

Indoor and outdoor temperatures

-30

-20

-10

0

10

20

30

40

1 10 19 28 37 46 55 64 73 82 91 100 109 118 127 136 145 154 163

time (hour)

t e m p e r a

t u r e

( o C )

Tout

Tin,n

5 m 2 glazing, 1000 kg water


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Building AmericaUSDOE-sponsored partnerships between consultingengineers and building industry, leading toprototypes and large-scale production

~33,000 houses constructedGoalsDesign and construct more energy efficient homesReduce construction costs to provide more affordable

housingImprove comfortImprove health and safety and indoor air qualityIncrease resource use efficiency

Increase building durabilityEnergy target: 35-45% reduction in heating, coolingand hot-water energy use


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Glazing

http://www.efficientwindows.org/BuilderToolkit.pdf

visible

Full spectrum

~1/2 visible,1/2 infrared

Window Visible

transmittance

Solar heat

gaincoefficientSingle clear 0.90 0.86Double clear 0.81 0.76Double low e 0.76 0.65Double low e tint 0.45 0.35Double low e, Ar fill,spectrally selective

0.72 0.40

$0

Single clear Aluminum frame

6% Savings #

16% Savings #

32% Savings #

Single tintAluminum frame

Double clear Wood/Vinyl frame

Double clear Low-solar-gain low-E

Wood/Vinyl frame

Window Type$200 $400 $600 $800

$0

Single clear Aluminum frame

27% Savings #

# Compared to the same 2000 sf house with clear, single glazing in an aluminum frame.

32% Savings #

39% Savings #

Double clear Wood/Vinyl frame

Double clear High-solar-gain low-E

Wood/Vinyl frame

Triple clear Mod.-solar-gain low-E

Insulated frame

Window Type$400 $800 $1200 $1600

Annual Cooling Energy Cost for a Typical House in Phoenix, AZ

Annual Heating Energy Cost for a Typical House in Boston, MA

Figure by MIT OCW.


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The builders perspective: pros and cons

Durability is keyBetter moisture managementFewer warranty problemsHappier customers and buildersMore referrals, sales

Less construction waste

Fewer dumpstersReduced tipping fees

New construction system to learnNew concepts may require changes to local buildingcodes


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The systems approachFeature Minneapolis Grayslake,

ILAtlanta Tucson Banning,

CAAdvanced framing -250 -250 +250Insulating sheathing 0 +400Insulate basement +600Slab-edge insulation +200Unvented, conditioned attic +750 +750

Eliminate roof vents -500Eliminate housewrap -400High-performance windows +250 +1,000 +250 +300 +750Reduce infiltration +100Controlled ventilation system +150 +125 +150 +150 +250Locate ducts in conditioned

space

0

Simplify or downsize ductdistribution

-250 -300

Downsize air conditioner -350 -750 -750 -1,000High-efficiency, direct-ventfurnace

+750 +400 +400

Power-vented gas water heater +300 +150Dehumidifier +175Set-back thermostat +100Total premium -150 +1,525 -25 +100 +2,150Annual homeowner savings 225 480 400 390 370

R f i


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Refrigerators

Source: Collaborative Labeling and Appliance Standards Program

01960 1970 1980

Time (years)

1990 2000

400

A n n u a

l e n e r g y c o n s u m p t

i o n

( k i l o W a t

t - h o u r s )

800

1200

1974, California law authorizesenergy-efficiency standards (1,825 kWh)

1977, first California standards take effect (1.546 kWh)

Average before U.S. standards(1,074 kWh)

1990 U.S. standard (976 kWh)



1600

2000

Figure by MIT OCW.


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Lighting efficacies

Source: IESNA

0 20

Standard IncandescentTungsten Halogen

Halogen Infrared Reflecting

Mercury Vapor

Metal Halide

White Sodium

Compact Metal Halide

High Pressure Sodium

Fluorescent (Full size and U-tube)

Compact Fluorescent (5-26 watts)Compact Fluorescent (27-40 watts)

40 60

Lumens/wattlamp plus ballast

80 100

Figure by MIT OCW.


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Potential gain from solid-state lighting

Source: Sandia National Lab

19700

100

200

1980 1990Year

E f f i c i e n c y ( l m / W )

2000

Fluorescent

Halogen

Semi-conductor withoutacceleratedeffort

with acceleratedeffort

Projected

Incandescent

2010 2020

Figure by MIT OCW.


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Residential clothes washers andcentral A/C

Washing machine energy

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

Federal2004

Energy Star 2004

Aailable2006

Federal2007

Energy Star 2007

k W h / c y c l e

Residential A/C peak power

0

1

2

3

4

5

6

1978average

Federal1992

Federal2006

EnergyStar 2006

Available2006

GSHP2006

p e a k - l o a d

k W

Manufacturers identify Energy Star products. A/C andfurnace/boiler producers list efficiencies but clothes washermanufacturers do not tout energy consumption for their

equipment, which only costs ~$20/year in electricity


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Lakeland, Florida, PV houseAnnual energy use, kWh

2500

4700

18400

net PV efficiency

Better choice of envelope construction woulddrop payback period from 23 to 9 yearswithout PV and 40 to 28 years with PV.

Photograph of a

photovoltaic house.Image removed forcopyright reasons.

Habitat for H manit ho ses Tennessee


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Habitat for Humanity houses, Tennessee Oak Ridge National Lab

Five low-energy houses with very advanced technologies:wall panels, mechanical ventilation, waste-heat scavengingfor hot water, PVHeating, cooling and hot water costs about $0.70/ day (!!)

Other costs $1.00-1.38/day Christmas lights (!!)Research houses: not cost effective locally ($20K efficiencyinvestment to save $400/year)


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NRELs rational approach to efficiency

and zero-net energy in houses

Source:

Ren Anderson, NREL

Automated search for best combination of


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Automated search for best combination of improvements

Tuning efficiency investments for a


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Tuning efficiency investments for agiven location


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PV is expensive, at least for now

Location

Atlanta

Chicago

Houston

Phoenix

San Francisco

32

28

38

39

27

1,749

3,899

2,585

2,585

1,337

49

46

51

52

43

10,351

15,168

8,762

9,553

8,432

42,000

57,000

46,500

40,500

36,000

PV cost

Present valueof efficiency

investment, NZE, $

Savings atminimum

cost, %

Savings at

NZE, %

Present valueof efficiencyinvestment,

minimum cost,$

Figure by MIT OCW.


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Solar Decathlon National Mall 2005


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Canadian Solar Decathlon House

Heat recovery from PV boosts efficiency from ~8% to ~35%


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3. Commercial buildings

Systems approach is lackingNo Building America equivalent

Optimization tools are not as well developedStandards do not take systems approachFew buildings go beyond basic code compliance

Notable successesIndividual buildings, 1/3 -1/2 below averageExpanding data base of high-performancebuildings

Private-sector labeling program (LEED) a helpGuideline for small commercial buildings

Massachusetts State Transportation Building


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Massachusetts State Transportation Building,Boston: a 20-year oldie but goodie

Aerial photograph of the StateTransportation Building.

Image removed for copyright reasons.

Atrium as thermal buffer source of daylight


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Atrium as thermal buffer, source of daylightand central plaza

Photographs of atrium.

Images removed for copyright reasons.

Whats missing in this schematic?


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Hint: not what you would expect in New England winters

Storage Tank 3

AC-2coolingcoil

AC-3coolingcoil

HE-3

HWR

CHWR

AC-4coolingcoil

Storage Tank 3HE-2

Storage Tank 1

KEY

HWSCHWS

CWR

Hot water pumps

Perimeter

Condenser water pumps

CWS

CT-1 CT-2

Chilledwater pumps

Zones

RU-2 RU-3

HE-1

HWS = Hot water supply HWR = Hot water return CWS = Condensed water supply CWR = Condensed water returnCHWS = Chilled water supply CHWR = Chilled water return

AC-1coolingcoil

RU-1

Figure by MIT OCW.

Potential for wasted energy: simultaneous (same


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Potential for wasted energy: simultaneous (sameinstant, same day) heating and cooling

Mild weather: perimeter mayneed heat in early morning,cooling in afternoon (likehouses)

Year-round: core needs

cooling constantly, evenwhen perimeter must beheated

Perimeter zone

Core


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Energy consumption

173 kWh/m 2 year (277 US average)End use energy:

Lights 41.6% (13.7 W/m 2 peak)Variable mechanical 26.1%Steam 11.2%Appliances 5.4%Elevators 6.2%

Computer rooms 5.4%Base mechanical 4.0%


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Is this a low-energy building?

173 kWh/m2 yr transp bldg653 state office bldg717 state office bldg270 comm office bldg

196 comm office bldg186 comm office bldg

The lower-energy buildings all recoverheat from the building core

ff


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UK Office #1Three-story officebuilding5,100 m 2 (54,900ft 2) net floor areaSealed windows100% mechanical

conditioning1+ year of monitoring andmodeling

Photograph of office building.Image removed for copyright

reasons.


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Open atrium but closed conference rooms

Photographs of atrium.

Images removed for copyright reasons.

Ai fl M


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Airflow MeasurementsVery important!! Air must be heatedor cooled, seasonally

40 L/s-person

About four times coderequirements

One-half expected occupancyConference rooms controlleddesign

Heat-recovery system broken

Photograph of people takingairflow measurements.

Image removed forcopyright reasons.

CO 2 in conference rooms


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CO 2 in conference rooms

CO 2 levels were typically well below the 1000 ppm limit

0

C O 2

L e v e l s

( p p m

)

Sun12am

Mon12am

Mon12pm

Tue12am

Tue12pm

Wed12am

Wed12pm

Thur 12am

Thur 12pm

Fri12am

Fri12pm

Sat12am

Sat12pm

Outside CO 2 Levels= 415 ppm

Sun12pm

400

600

200

800

1000

1200

Figure by MIT OCW.

Savings due to heat recovery and lower airflowCO emissions kg/m 2


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CO 2 emissions, kg/mEnergy consumption, kWh/m 2

Natural gas Electricity Total

Current 30.8162

71.7156

102.5318

Currentairflow andheat recovery

19.8104

71.7156

91.5260

Reducedairflow andheat recovery

24.7130

45.098

69.7228

Savings potential due to betteri f b ildi


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operation of buildings

California: energy crisis9% electrical demand reduction in 2001

relative to 2000, due to increased pricesTexas: continuous commissioning

20+% energy savings in 100+ largebuildings, less than 3 year paybackFor 20 buildings

28% savings in chilled water

54% savings in hot water2-20% savings in electricity (fans, pumps)

UK Office #2: nearby, naturally ventilated


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building

The following pages containedphotographs of the office building,atrium views, interior views

including windows and blinds,exposed structural mass, and open

doors for airflow.

Images removed for copyrightreasons.

I t i T t J l 2003


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Interior Temperatures: July 2003

Luton July 2003

0

5

10

15

20

25

30

35

40

45

7 / 2 3 / 0 3 1 2 : 0

0 A M

7 / 2 3 / 0 3 4 : 4

5 A M

7 / 2 3 / 0 3 9 : 3

0 A M

7 / 2 3 / 0 3 2 : 1

5 P M

7 / 2 3 / 0 3 7 : 0

0 P M

7 / 2 3 / 0 3 1 1 : 4

5 P M

7 / 2 4 / 0 3 4 : 3

0 A M

7 / 2 4 / 0 3 9 : 1

5 A M

7 / 2 4 / 0 3 2 : 0

0 P M

7 / 2 4 / 0 3 6 : 4

5 P M

7 / 2 4 / 0 3 1 1 : 3

0 P M

7 / 2 5 / 0 3 4 : 1

5 A M

7 / 2 5 / 0 3 9 : 0

0 A M

7 / 2 5 / 0 3 1 : 4

5 P M

7 / 2 5 / 0 3 6 : 3

0 P M

7 / 2 5 / 0 3 1 1 : 1

5 P M

7 / 2 6 / 0 3 4 : 0

0 A M

7 / 2 6 / 0 3 8 : 4

5 A M

7 / 2 6 / 0 3 1 : 3

0 P M

7 / 2 6 / 0 3 6 : 1

5 P M

7 / 2 6 / 0 3 1 1 : 0

0 P M

7 / 2 7 / 0 3 3 : 4

5 A M

7 / 2 7 / 0 3 8 : 3

0 A M

7 / 2 7 / 0 3 1 : 1

5 P M

7 / 2 7 / 0 3 6 : 0

0 P M

7 / 2 7 / 0 3 1 0 : 4

5 P M

7 / 2 8 / 0 3 3 : 3

0 A M

7 / 2 8 / 0 3 8 : 1

5 A M

7 / 2 8 / 0 3 1 : 0

0 P M

7 / 2 8 / 0 3 5 : 4

5 P M

7 / 2 8 / 0 3 1 0 : 3

0 P M

7 / 2 9 / 0 3 3 : 1

5 A M

7 / 2 9 / 0 3 8 : 0

0 A M

7 / 2 9 / 0 3 1 2 : 4

5 P M

7 / 2 9 / 0 3 5 : 3

0 P M

7 / 2 9 / 0 3 1 0 : 1

5 P M

T e m p e r a

t u r e

( C )

ground floor average

first floor average

second floor average

outside

I t i T t A t 2003


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Interior Temperatures: August 2003

Luton August 2003

0

5

10

15

20

25

30

35

40

45

8 / 1 / 2 0 0 3

8 / 1 / 2 0 0 3

8 / 2 / 2 0 0 3

8 / 3 / 2 0 0 3

8 / 4 / 2 0 0 3

8 / 5 / 2 0 0 3

8 / 6 / 2 0 0 3

8 / 6 / 2 0 0 3

8 / 7 / 2 0 0 3

8 / 8 / 2 0 0 3

8 / 9 / 2 0 0 3

8 / 1 0 / 2 0 0 3

8 / 1 1 / 2 0 0 3

8 / 1 1 / 2 0 0 3

8 / 1 2 / 2 0 0 3

8 / 1 3 / 2 0 0 3

8 / 1 4 / 2 0 0 3

8 / 1 4 / 2 0 0 3

8 / 1 5 / 2 0 0 3

8 / 1 6 / 2 0 0 3

8 / 1 7 / 2 0 0 3

8 / 1 8 / 2 0 0 3

8 / 1 9 / 2 0 0 3

8 / 1 9 / 2 0 0 3

8 / 2 0 / 2 0 0 3

8 / 2 1 / 2 0 0 3

8 / 2 2 / 2 0 0 3

8 / 2 3 / 2 0 0 3

8 / 2 4 / 2 0 0 3

8 / 2 4 / 2 0 0 3

8 / 2 5 / 2 0 0 3

8 / 2 6 / 2 0 0 3

8 / 2 7 / 2 0 0 3

8 / 2 8 / 2 0 0 3

8 / 2 9 / 2 0 0 3

8 / 3 0 / 2 0 0 3

8 / 3 0 / 2 0 0 3

8 / 3 1 / 2 0 0 3

T e m p e r a

t u r e

( C )

outside

First floor average

Ground floor average

Second floor average

Results from occupant survey views on temperature


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Results from occupant survey views on temperature

0Neutral

Temperature

20 Slightlywarm

Warm1) Warm inside building

this summer but...

2) Not overly hot formost occupants

Hot

Too Hot

O c c u p a n t

R e s p o n s e

( % )

40

60

80

100

Figure by MIT OCW.

Comparison of UK #1 and UK #1,kWh/m2 year


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kWh/m2 year

MV std MV GP NV std NV GP SunburyA

Luton

TotalNG

178 97 151 79 162 140

Totalelec

226 128 85 54 156 76

L +OE 85 50 65 42 55 51

Refrig 31 14 0 0 29 0

Fans +cntls

60 30 8 4 50 5

UK #1 UK #2


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Dealing with conference rooms:San Francisco Federal Building

Faade details coordinated


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Trickle vent and heater

at floor Manual operable window

at desk height Motorized window above

2 4 0 0

2 8 0 0 ( T o p o f c a

b i n )

3 0 5 0 ( c o n c .

l o w

p t . ) 3

2 5 0 ( c o n c .

h i g h p

t . )

8 0 0

1 3 5 0

7 4 0

8 7 0

2250 @ 14 th Floor (width Varies)

PERFSUNSCREEN

WINDOW WALL CONDITIONTYP BOTH SIDES MAX

ALLOW CLEAR OPENING TOBE 90MM TYP

Figure by MIT OCW.

Testing the configuration: predicted


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Testing the configuration: predicted

degree-hours above base temperature

Basetemperature ( oF)

Windonly

Internalstack

Int & extstack

Int stack +wind

Int & ext stack +wind

72 288 507 432 279 285

75 80 118 103 76 76

78 13 25 19 11 12

DOEs high performance buildingsdata base


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data base4 Times Square 201 kWh/m 2simulated; daylight, fuel cells,a little PV

EPA office, NC, 89 kWh/m 2

simulated; shading, daylight,outside air when suitable

Chesapeake Bay Foundation


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Chesapeake Bay Foundation, Annapolis 131 kWh/m 2 measured

consumption, 117 kWh/m 2 purchased, 10% of consumed energygenerated from solar thermal and PV on site; shading, daylight, naturalventilation, ground-source heat pumps

0%

Fans/pumps

Lights Plug loads

Cooling Other

Heating

26%

20%

26%

20%8%

Figure by MIT OCW.

Zion National Park Visitor Center


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Zion National Park Visitor Center

Image courtesy of the National Park Service.

California Courthouse


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candidate for night cooling

Photograph of courthouse windows.

Image removed for copyright reasons.

Annual Building-Total Electricity CostsR t h t


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0

Case #

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

40 A n

n u a

l E l e c

t r i c i t y C o s t

( k $ / y e a r )

80

120

160

200

Ratchet

On-Peak kW

Mid-Peak kW

On-Peak kWh

Mid-Peak kWh

Off-Peak kWh

Figure by MIT OCW.

Energy Design Guide for Small(< 20,000 ft 2) Commercial Buildings


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( 20,000 ft ) Commercial Buildings

30% savings relative to 1999 standardStrategies

Reduce loadsUse properly sized, efficient equipmentRefine systems integration

Climate-specific prescriptiverecommendations:

roof, walls, floors, slabs, doors

windows, skylights, lightingHVAC, ventilation, and hot water

4. Good enough?


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g

Lifestyle vs. efficiencyMarket acceptance and technologygains for lights, appliances and HVACGrowing but still modest evidence of

cost-driven efficiency gainsOpportunity to contribute to carbonstabilizationIntegrated design needs to be pushed

Floor area counters efficiency gains


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y g

Source: LBNL report

01950 1960

Year

1970 1980 1990 2000

500

1000

1500

2000

2500

Single-family (mean)

Single-family(median)

US New HousingFloor Area: Single-Family

(1950-2000)

Floor area/cap

Figure by MIT OCW.

Major potential gains from market


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acceptanceCFL sales up 10x in Northwest, 2001 2004, but only 11% of market during

energy crisis(source: J. DiPeso)

High-efficiency appliances and HVAC are onthe market now

Clothes washers 2x code efficiencyResidential A/C 1.5x code efficiency

Near-maximum efficiency gains have been

realized in some cases: fridges, furnaces

Atmospheric CO 2 stabilization wedgesPacala and Socolow


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Efficiency option: cut building and appliance emissions by 25% relative to business as usual

Renewable electricityand fuels

CO 2 captureand storage

Forests andsoils

Nuclear Fission

2004

Stabilization

Triangle

2054

14 GtC/y

7 GtC/y

Fuel switch

Energy efficiencyand conservation

Figure by MIT OCW.

To-do listPromote market acceptance


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Promote market acceptance

InformationCarbon taxEmissions trading at micro-level

Work to do

Cheaper, more efficient technologiesLightsPV, using waste heatVentilation: demand-controlled, heat recovery,night cooling

Ubiquitous integration tools for new construction andretrofits

Individual buildings

Communities (heat capture, local powergeneration)Component-level optimization is NOT enough!!Think at systems level.

mit ocw cee 1-964 - design for sustainability - energy in buildings

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