Dr. Sarah Outcault
Western Cooling Efficiency Center,
University of California-Davis

BECC Japan - 9/16/14

Total household energy consumption*• Total energy
consumption is 2.2
times greater in U.S.
than Japan• Gas consumption is
4 times higher inU.S. than Japan

Source:Jyukankyo Research Institute Inc., 2014

*Includes oil, gas, kerosene/LPG,electricity

Total electricity consumption
kWh/household
14000
12000
10000

9447

9965

10219

10656

11480

11320

8000

US

6000
4000

3658

3949

4541

4883

5176

5286

2000
01990

1993

1997

2001

2005

2009

Sources:2014 Household Energy Handbook (家庭用エネルギーハンドブック」、住環境計画研究所 編。)

Residential Energy Consumption Survey.

JapanResidential electricity prices are low
Yen/kWh30.0
25.0

24.4

24.6

23.6

20.0

21.4

22.0

21.0

Japan

15.0
10.0

11.3
7.9

8.8

10.5

10.1

9.5

5.0
0.0
1990

1995

2000

2005

2010

2012

Sources:2014 Household Energy Handbook (家庭用エネルギーハンドブック」、住環境計画研究所 編。)
Form EIA-861, "Average price by state by provider, back to 1990". U.S. Energy Information Administration.
Oanda.com

USResidential gas prices are low
Yen/kWh180.0
160.0
140.0
120.0
100.0
80.0
60.0
40.020.0
0.0

145.4

141.5

146.9

145.3

153.6

165.7

Japan

US
49.4
29.6
1990

20.1
1995

35.3

29.5
2000

2005

2010

30.2
2012

Sources:2014 Household Energy Handbook (家庭用エネルギーハンドブック」、住環境計画研究所 編。)
Form EIA-861, "Average price by state by provider, back to 1990". U.S. Energy Information Administration.
Oanda.com

Household and housing characteristics matter

JAPANUSA

Sources:
Appendix of 2008 Household and Land Census, Statistics Japan.
United States: 2010 Summary Population and Housing Characteristics, United States Census Bureau.
American Housing Survey for the United States: 2011, United States Census Bureau.

ASHRAE Standard 55 defines “thermal comfort”• Defines “comfortzone”• Usually invoked as adesign standard: amechanical system
has to be “capable” ofgetting you in thecomfort zone.
• Often used as an
operational standard

Range of thermal comfort standards is narrow

JapanUSAJapan
USA

Sources:
Japan: http://www.crecer.jp/Q-A/HTML/A-11.html; US: ASHRAE guidelines

Low

High25222827Low

High18202223

Climate drives energy use
Electricity Consumption in Northern California, by Climate Zone

Source: Lutzenhiser and Bender, 2008 (ACEEE Summer Study)

Types of Behaviors That Can Save Energy

Source: Paving the Way for a Richer Mix of Residential Behavior Programs: CALMAC.org #SCE0334.01

Policies to reduce residential energy use emphasize
technical “solutions”• Focus on efficiency• California has strict
energy efficiency codes
for new buildings• Focus on home
automation• Zero-net energy (ZNE) asa “solution”• All new residential
construction in
California must by ZNE
by 2020

Case study of West Village:
ZNE community in Davis, CA (U.S.)
Sponsored by:West Village overview•••

UC Davis land (130 acres), with private developer
ZNE (solely electric; solar PV)
Mixed-use community• Housing: Student residences (2000 students) + 343 faculty/staff units• 60,000 sqft commercial spaceApartment in West Village

Progress to ZNE target• WV is currently 15%
above predicted model
consumption forelectricity overall• 118% above
predicted model for
HVAC consumption• Several behavioral
interventions havebeen tried by WCEC
and others

Intervention: Reminders, feedback, and accountability• Targeted energy-saving
actions:• Turn off PC at night• Hang dry towels• Provided tools to help carryout the actions• Provided devices to:• remind them to carry outthe actions• allow them to reportcarrying out the action• provide encouragement
when they have carriedout the action

Intervention: Education & Awareness• Reprogramming thermostats
to “auto” instead of “on” toreduce fan operations• Set points, 75 degrees max.
for heating, 70 degrees min.
for coolingSource: NORESCO Report, 2014

West Village electricity consumption from HVAC
• Wide spread
between lowand high users
during coolingseason• Average >modelassumption

Source: NORESCO Report, 2014

Intervention: Promoting passive coolingMonthly average temperature (F)Sources: Japan Meteorological Agency; National Oceanic & Atmospheric Administration

How important are the following when cooling yourapartment?
12# of respondents

10
864

2

Very Important

ImportantSomewhat Important
Somewhat Unimportant
Unimportant

Very unimportant0

Which best describes your sensitivity to heat on hot days?

14# of respondents

12
10
86
4
20
I don’t like to be hot.

I don’t mind being
warm/somewhat hotwhen it’s hot outside.

I don’t mind being
warm/somewhat hotwhen it’s hot outside, if itsaves energy.

What’s the highest acceptable temperature in yourapartment in summer?

How often do you open your window(s) at night?
10
86
4
20
Never

Once a week

A few nights a Most nights
Every nightweek
during the weekduring the week

How often does your apartment’s AC run at night?

# of respondents

8
6
4

20
0

1

2

3

4night(s) per week567

How interested are you in trying “natural” (passive)
cooling?
10# of respondents

86420
Very
Interested

Interested

Somewhat
Interested

Disinterested

Not at all
Interested

Are you willing to commit to trying “natural” (passive)
cooling this August?

YesNoChallenges to encouraging conservation through passivecooling• West Village residents do not pay for electricity• Complained of discomfort, noise and safety concernswith open windows• Privacy trumps cross ventilation• Roommates make independent decisions, not joint
onesChallenges to conservation efforts more broadly• Financial motivation is lowfor many
• Comfort is paramount• Americans have balked atrequests to sacrifice or
be uncomfortable• BUT… other behavioral
drivers have had somesuccess (e.g., OPower)

Thank you.
Questions?
Contact me:

Dr. Sarah Outcault
smoutcault@ucdavis.edu
Western Cooling Efficiency Center

University of California-Davis