POST-OCCUPANCY EVALUATIONS OF

HIGH-PERFORMANCE HOMES

Tenna Florian

Hazem Rashed-Ali

Hacienda Ja Ja: A High Performance Home Lake | Flato Architects

“THERE are NO ZERO-ENERGY HOUSES, only

ZERO-ENERGY FAMILIES.”

- Andy Shapiro, energy consultant

Construction Period: January 2009 to May 2010 (move in)

Conditioned Space: 2,330 square feet

Unconditioned Space: 950 square feet

Architect: Lake | Flato Architects (Tenna Florian, Bill Aylor, Josh Canez, Gus Starkey)

Contractor: Truax Construction (Jeff Truax)

Interior Design: M. Robbins Black (Robin Black)

Landscape Design: Rialto Studio (Pete Hinton)

Lighting Design: George Sexton Associates (George Sexton)

Structural Engineer: Jack Harrison

Solar: Cinco Solar

Mechanical: Southwest Mechanical

TEAM

STATS

LEED Highlights: Platinum Project: 87 points needed and 89.5 achieved

Locations and Linkages: 10 of 10 points available

infill, previously developed, and good access to transit

Sustainable Sites: 14.5 of 22 points available

site stewardship, native landscaping, reduced heat island effect, permeable lot

Water Efficiency: 11 of 15 points available

rainwater harvesting, irrigation demand reduction, and highly efficient fixtures

Energy & Atmosphere: 33 of 38 points available

optimize energy performance, efficient hot H2O systems, appropriate refrigerants

Materials and Resources: 7.5 of 16 point available

environmentally preferable products, waste reduction plan

Indoor Environmental Quality: 11 of 21 points available

moisture control, outdoor air ventilation, local exhaust, ventilated garage

Water Efficiency: 11 of 15 points available rainwater harvesting, irrigation demand reduction, and highly efficient fixtures

Energy & Atmosphere: 33 of 38 points available optimize energy performance, efficient hot water systems, appropriate

refrigerants

Hacienda Ja Ja: A High Performance Home Lake | Flato Architects

POST-OCCUPANCY EVALUATION

OBJECTIVES:

• Verify overall house energy use,

• Compare actual energy use with predicted

energy use,

• Identify potential for performance

improvement,

• Assess success of design strategies,

Hacienda Ja Ja

MONITORING PERIOD:

System installed on Nov. 11, 2010 to present.

Monitoring period reported: January 1, 2011 through December 31, 2011.

Four small periods of communication loss due to power outage (less than 1 hr. each).

One larger period of communication loss (June 13 through 17).

BUILDING OCCUPANCY:

Building not regularly occupied during monitoring period.

Occupancy period approximately one third of the year.

Monitoring / Occupancy Period

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Jan

-11

Feb

-11

Mar

-11

Ap

r-1

1

May

-11

Jun

-11

Jul-

11

Au

g-1

1

Sep

-11

Oct

-11

No

v-1

1

Dec

-11

Pe

rce

nta

ge o

f D

ays

Month Monitored/ Occupied Monitored/ Not Occupied Not Monitored

MONITORING EQUIPMENT: eMonitor:

One eMonitor 12r installed.

Monitors PV power production &

energy use at circuit level.

System online interface

HOBOs:

Five HOBO U12-012 Data loggers

installed.

Monitors temperature, humidity,

lighting levels.

LOCATION OF MONITORING EQUIPMENT

eMonitor-12r

Hobo-U12-012

Post-Occupancy Evaluation

Monitoring equipment

• eMonitor:

• One eMonitor 12r installed.

• Monitors PV power production

& energy use at circuit level.

• System online interface

• HOBOs:

• Five HOBO U12-012 Data

loggers installed.

• Monitors temperature, humidity,

lighting levels.

THE FOLLOWING ISSUES WERE IDENTIFIED / CORRECTED

DIRECTLY OR PARTIALLY DUE TO MONITORING SYSTEM:

Kitchen Instantaneous Water Heater Usage

Solar Domestic Hot Water Pump

HVAC Dehumidifier Settings

PV System Blown Circuit

Green Switch

turned on

User in

house

User left heater on while building was unoccupied resulting in approx. 7

kWh/day usage.

Issue identified from monitoring, resulting in user changing behavior.

51%

17%

20%

1% 7% 3%

64%

22% 1% 9%

4%

Turning off the Kitchen Water

Heater reduced the house’s total

Energy Usage 20%.

0%

0%

Data taken from 24 hr. time frame

Data taken from 24 hr. time frame

User changed

settings

User left AC on dehumidifier setting while the building was unoccupied- resulting

in a high AC energy usage.

Issue identified through monitoring and resulted in user changing behavior.

Problem identified (system

off-line).

Problem fixed (system

online)

Pump stopped working, hot water provided by auxiliary electric heating.

Issue identified through user observation (hot water insufficient), and confirmed using

monitoring system.

Problem fixed

Low PV production issue Identified by user.

PV installer initially blamed resource variability.

Upon user insistence, inspection showed a blown circuit in resulting in 50%

reduction of production.

Problem started

Preliminary Results – Overall Energy Use:

-500

0

500

1,000

1,500

2,000

Jan

-11

Feb

-11

Mar

-11

Ap

r-1

1

May

-11

Jun

-11

Jul-

11

Au

g-1

1

Sep

-11

Oct

-11

No

v-1

1

Dec

-11

Ene

rgy

Use

(kW

h)

Months

Utility Energy Use Building Energy Use PV Poduction

OVERALL ENERGY USE - 2011:

1,916

11,288

9,372

0

2,000

4,000

6,000

8,000

10,000

12,000

14,000En

erg

y U

se (

kWh

)

2011 Energy Use Totals

Utility Energy Use Building Energy Use PV Poduction

ENERGY USE INTENSITY (EUI) - 2011:

2.8

16.5

13.7

0.0

2.0

4.0

6.0

8.0

10.0

12.0

14.0

16.0

18.0En

erg

y U

se In

ten

sity

(kB

tu/f

t2/y

r)

2011 Energy Use Intensity

Utility Energy Use Building Energy Use PV Poduction

PRELIMINARY RESULTS: energy + cost

HISTORY

ENERGY END USES - 2011:

0

200

400

600

800

1,000

1,200

1,400

1,600

Jan

-11

Feb

-11

Mar

-11

Ap

r-1

1

May

-11

Jun

-11

Jul-

11

Au

g-1

1

Sep

-11

Oct

-11

No

v-1

1

De

c-1

1

Ene

rgy

Use

(kW

h)

Months

HVAC

Dryer

Oven

Kitchen WaterHeater

DHW

Lights /Plug Loads

ENERGY END USES EUI - 2011:

0.00

0.50

1.00

1.50

2.00

2.50

Jan

-11

Feb

-11

Mar

-11

Ap

r-1

1

May

-11

Jun

-11

Jul-

11

Au

g-1

1

Sep

-11

Oct

-11

No

v-1

1

Dec

-11

End

En

erg

y U

se In

ten

sity

(kB

tu/f

t2/y

r)

Months

HVAC

Dryer

Oven

Kitchen WaterHeater

DHW

Lights /Plug Loads

ENERGY END USES - 2011:

1,274, 11%

399, 4%

1,057, 10%

153, 1%

21, 0%

8,113, 74%

Total Energy End Uses (kWh)

Lights /Plug Loads

DHW

Kitchen WaterHeater

Oven

Dryer

HVAC

ENERGY END USES INTENSITY - 2011:

1.87, 11%

0.58, 4%

1.55, 10%

0.22, 1%

0.03, 0%

11.88, 74%

End Energy Use Intensity (kBtu/ft2)

Lights /PlugLoads

DHW

Kitchen WaterHeater

Oven

Dryer

HVAC

COOLING SEASON DEMAND:

Hottest Day - August 28 (Building Unoccupied)

20

30

40

50

60

70

80

90

100

110

-3.0

-2.0

-1.0

0.0

1.0

2.0

3.0

4.0

5.0

6.0

0:0

0

1:0

0

2:0

0

3:0

0

4:0

0

5:0

0

6:0

0

7:0

0

8:0

0

9:0

0

10

:00

11

:00

12

:00

13

:00

14

:00

15

:00

16

:00

17

:00

18

:00

19

:00

20

:00

21

:00

22

:00

23

:00

Tem

pe

ratu

re (

F)

Po

wer

Dem

and

(kW

)

Hour of Day

BuildingDemand

Utility EnergyUse

PV Production

AC USE

AmbientTemperature

20

30

40

50

60

70

80

90

100

110

-3.0

-2.0

-1.0

0.0

1.0

2.0

3.0

4.0

5.0

6.0

0:0

0

1:0

0

2:0

0

3:0

0

4:0

0

5:0

0

6:0

0

7:0

0

8:0

0

9:0

0

10

:00

11

:00

12

:00

13

:00

14

:00

15

:00

16

:00

17

:00

18

:00

19

:00

20

:00

21

:00

22

:00

23

:00

Tem

per

atu

re (

F)

Po

wer

Dem

and

(kW

)

Hour of Day

BuildingDemand

UtilityEnergy Use

PVProduction

AC USE

AmbientTemperature

COOLING SEASON DEMAND:

Hottest Occupied Day (August 2)

-30

-20

-10

0

10

20

30

40

50

60

-3.0

-2.0

-1.0

0.0

1.0

2.0

3.0

4.0

5.0

6.0

0:0

0

1:0

0

2:0

0

3:0

0

4:0

0

5:0

0

6:0

0

7:0

0

8:0

0

9:0

0

10

:00

11

:00

12

:00

13

:00

14

:00

15

:00

16

:00

17

:00

18

:00

19

:00

20

:00

21

:00

22

:00

23

:00

Tem

per

atu

re (

F)

Po

wer

Dem

and

(kW

)

Hour of Day

BuildingDemand

UtilityEnergy Use

PVProduction

AC USE

AmbientTemperature

HEATING SEASON DEMAND:

Coldest Day – February 2nd (Building Unoccupied)

-20

-10

0

10

20

30

40

50

60

70

80

90

-5.0

-4.0

-3.0

-2.0

-1.0

0.0

1.0

2.0

3.0

4.0

5.0

6.0

0:0

0

1:0

0

2:0

0

3:0

0

4:0

0

5:0

0

6:0

0

7:0

0

8:0

0

9:0

0

10

:00

11

:00

12

:00

13

:00

14

:00

15

:00

16

:00

17

:00

18

:00

19

:00

20

:00

21

:00

22

:00

23

:00

Tem

per

atu

re (

F)

Po

wer

Dem

and

(kW

)

Hour of Day

BuildingDemand

UtilityEnergyUsePVProductionAC USE

AmbientTemperature

HEATING SEASON DEMAND:

Coldest Occupied Day – November 27th

COMPARISON WITH RECS & REM RATE

MODEL: 1) Average EUI

based on

RECS 2005

data.

2) REM Rate

estimates

based on

design-stage

analysis

3) Actual EUI

based on

consumption

from 1/1/2011

through

12/31/2011

37.6

30.1

19.8

8.04

16.5

2.8

0

5

10

15

20

25

30

35

40

Average TXHome

Average TXHome (Mod.)

REM RateModel (Building

Energy Use)

REM RateModel (UtilityEnergy Use)

Hacienda HaHaEUI (BuildingEneryg Use)

Hacienda HaHaEUI (UtilityEnergy use)

Ener

gy U

sae

Inte

nsi

ty (

kBTU

/ft2

/yr)

Energy Use Intensity (kBTU/ft2/yr)

7,795

9,372

11.9

14.3

0

2

4

6

8

10

12

14

16

18

20

0

1,000

2,000

3,000

4,000

5,000

6,000

7,000

8,000

9,000

10,000

REM Rate estimates Actual Production

PV

Pro

du

ctio

n (

kBtu

/sq

ft)

PV

Pro

du

ctio

n (

kWh

)

PV PRODUCTION: ACTUAL vs. REM RATE

1) Estimated

system size

(for REM Rate

model):

2) Actual System

Size: 7.5

KW

DAYLIGHT LEVELS

0

10

20

30

40

50

60

70

80

90

100

1 3 5 7 9 11 13 15 17 19 21 23

Day

ligh

t Le

vels

(FC

)

Hour of Day

Average Day - January

0

10

20

30

40

50

60

70

80

90

100

1 3 5 7 9 11 13 15 17 19 21 23

Day

ligh

t Le

vels

(FC

)

Hours of Day

Average Day - March

0

10

20

30

40

50

60

70

80

90

100

1 2 3 4 5 6 7 8 9 101112131415161718192021222324

Day

ligh

t Le

vels

(FC

)

Hour of Day

Average Day - April

0

10

20

30

40

50

60

70

80

90

100

1 3 5 7 9 11 13 15 17 19 21 23

Day

ligh

t Le

vel (

FC)

Hours of Day

Average Day - May

0

10

20

30

40

50

60

70

80

90

1000

:00

1:0

0

2:0

0

3:0

0

4:0

0

5:0

0

6:0

0

7:0

0

8:0

0

9:0

0

10

:00

11

:00

12

:00

13

:00

14

:00

15

:00

16

:00

17

:00

18

:00

19

:00

20

:00

21

:00

22

:00

23

:00

Day

ligh

t Le

vels

(FC

)

Hours of Day

Fully Cloudy Day - Occupied - December 21

DAYLIGHT LEVELS

CONCLUSIONS

• ROLE OF MONITORING IN IDENTIFYING:

• maintenance issues

• potential for performance improvement.

• OVERALL EVALUATION OF HOUSE ENERGY

PERFORMANCE.

• IMPACT OF IRREGULAR OCCUPANCY

• ACTUAL VS. MODELED ENERGY USE

THANK YOU,

Questions?