Future%20Comforts:%20Policy%20Studies%20Institute

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Future Comforts Policy Studies Institute
Do you want to control the Temperature?
Max Fordham
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• We can provide control of temperature
• People have preferences
• Control of temperature uses fossil fuel!
• But...
• People are adaptable
• How much control do we need?

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Heat Exchange of the Bodywith the Environment

• 1 kW/m2 Short Wave Radiation from the Sun

RESPIRATION
RADIATION
Wet Air Dry Air
35ºC 25ºC
EVAPORATION
CONVECTION
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Comfort Research Summary

• Bedford Air temperature Radiation UK, Early
  20th century
• Webb Equatorial Comfort Index Wet bulb
  temperature Enthalpy
• ASHRAE Air temperature, Humidity, Air
  speed. (Statistics), US, Mid 20th century
• Belding Hatch All Parameters, Simple
  Physics US, Mid 20th century
• Ole Fanger All Parameters ISO 7730. Recent.
• Dusan Fiala Develop Fanger add
  involuntary reactions. Recent.
• ASHRAE Consider Voluntary Reactions.

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Comfort Conditions by Fanger
Hot comfort boundary
Cold comfort boundary
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PsychrometricChart
129
Air leaving Body(35C, 100 r.H.)
Evaporation
Specific Enthalpy kJ/kg
83
Singapore(28C, 90 r.H.)
21.5
Convection
61
Moisture Content g Water/kg Air
Saudi Arabia(46C, 20 r.H.)
51
13.5
Average UK Winter(10C, 20 r.H.)
10
Room Condition(25C, 50 r.H.)
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Room UK Winter(20C, 10 r.H.)
1.5
Dry Bulb Temperature C
40
10
30
20
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Anecdotes

• Otterbourne 30C not enough to open sash
  windows
• 43 Gloucester Crescent Is it really 30 C?
• Hong Kong Teaching 27C 56 RH
  radiant temp air temp Light clothes no
  adjustment wanted 20 building
  professionals

QED
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References
1 Fordham S M. Building Physics - Reducing air
conditoining needs in extreme climates. CIBSE
Conference 1978. 2 Climate change and its
impact. Meteorological Office, 1998. 3 Health
Safety Executive. EH 40/97 Occupational
Exposure Limits 1997, Table 2 Page 22. (ISBN
0-7176-1315-1). 4 Total Carbon Cycle
(tba). 5 Nuclear Energy - the future climate.
The Royal Society and The Royal Academy of
Engineering, 1999 (ISBN 0-85403-5262). 6 Fanger
P O. Olf and decipol New units for preceived
air quality. Building Services Engineering
Research Technology, 1984. 7 Fiala D.
Dynamische Simulation des menschlichen
Wärmehaushalts und der thermischen Behaglichkeit.
De Montfort University, 1998. 8 Field Studies
of Thermal Comfort and Adaption. ASHRAE
Technical Data Bulletin, Volume 14, Number 1.
January 1998.