Incorporating comfort in the design of low energy buildings

Transcription

1 NCEUB Autumn Meeting, Edinburgh 2009 Incorporating comfort in the design of low energy buildings Atze Boerstra BBA Binnenmilieu & Eindhoven University of Technology, Faculty of Architecture, Building Physics & Systems departement

2 Winston Churchill: We shape our buildings, thereafter they shape us...

3 Central question: IS COMFORTABLE AND ENERGY EFFICIENT POSSIBLE?

4 A QUESTION OF ALL TIMES... Viking house, Trelleborg DK (1250)

5 NOT JUST IN THE MORE DEVELOPED COUNTRIES... Farmer s house, South / East Asia (2009)

6 ALSO IN MODERN, ENERGY EFFICIENT BUILDINGS... Upper market dwellings with mechanical supply and heat exchanger, Amersfoort NL (2000+)

7 ALSO IN OFFICES... XX office building Delft, architect: Jouke Post Energy performance: IEQ performance: quite good rather poor; 80% occupants complained about too low temperatures in winter and too high temperatures in summer

8 SOME SCIENTIFIC FINDINGS

9 Ad random relation energy use - Sick Building Symptoms? (Source: EU IAQ Audit project / Bluyssen et al, 1995)

10 LEED certified buildings more comfortable? (Source: Abbaszadeh, Huizenga et al, 2006)

11 Preliminary conclusion Comfortable AND energy efficient can go hand-in-hand. But... you need smart designers / operators dedicated to optimisation of not just energy use but also user comfort (health) and (life cycle) costs...

12 SOME EXAMPLES OF AND-AND SOLUTIONS

13 Optimise solar load in office rooms Office building TNO Delft, building physics consultant: mobius consult

14 Use of local climatisation in offices PERSONAL VENTILATION EXHAUSTO Individual control of air supply Connected to central ventilation system or pure recirculation Influences both local air quality and local thermal environment Standard feedback users: positive Impact on HVAC energy use: up to minus 40% (study CBE, California)

15 Local climatisation, poor man s version Kuchofuku jacket, Meadowness company, Japan

16 Optimise Indoor Air Quality in existing schools Busken Huet Primary School with CO 2 indicator, The hague (reopened by the Minister of Education)

17 Lower set point of central humidifier (or shutting if off all together)

18 Intermezzo: relative humidity and dry air complaints Source: Fang, Wyon & Fanger, 2003 Fang et al: Normally with cleain air relative humidity has no effect on perceived air quality ; conclusion: dry air complaints are caused by something else!

19 Raise temperature set point central cooling Over 70% of occupants complained of too low temperatures in summer Huygens Date: Tuesday July 1 st, 2008 Orientation room: South Sun hours: 87% (14,5 uur) T exterior, max : 27,7 C Temperature [ C] July 2 July Date [00:00 h]

20 Advised summer temperatures (ISO 7730) Temperature requirements - in 3 classes - in ISO 7730 and Pr EN for buildings with active cooling systems Type of building/ space Category Operative Temperature o C Offices and spaces with similar activity (single offices, open plan offices, conference rooms, auditorium, cafeteria, restaurants, class rooms, Sedentary activity ~1,2 met Heating (winter season), ~ 1,0 clo Cooling (summer season), ~ 0,5 clo A 21,0 23,0 23,5-25,5 B 20,0 24,0 23,0-26,0 C 19,0 25,0 22,0-27,0

21 Annex A2 EN Adaptive temperature limits in buildings without active cooling systems and operable windows (based on Nicol et al, 2007 SCATS database) 33,0 32,0 31,0 Θ o (ºC) 30,0 29,0 28,0 27,0 26,0 25,0 24,0 III II I 23,0 22,0 I 21,0 II 20,0 III 19, Θ rm (ºC)

22 Give user instruction about SUMMER clothing

23 Give user instruction about WINTER clothing

24 Introduce smart, assertive control knobs Wall thermostat alias energy saving coach (Ecobee) Ventilation control with filter-replacement indicator (Brink Climate Systems)

25 Intermezzo: taking individual control into account in future thermal comfort standards - WINTER proposal Class (category) Minimum indoor temperature (under winter design condition e.g. -10 C outside) Standard set point winter Personal control? Personal control bandwidth A+ 21 C 22 C Yes, at workstation level e.g. with hand/feet warmers or radiant table top A 21 C 22 C Yes, at room level e.g. with radiators with thermostatic knobs B 20 C 22 C Yes, at room level e.g. with radiators with thermostatic knobs C (-4/+2 C around set point) C (-4/+2 C around set point) C (-3/+1 C around set point) C 19 C 22 C No - (example office work; 1,2 met; 1,0 clo )

26 SUMMER proposal Class (category) Maximum indoor temperature (under summer design situation e.g. +30 C outside) Standard set point summer Personal control? Personal control bandwidth A+ 25,5 C 24,5 C Yes, at workstation level e.g. with a Personal Ventilation system or table fan A 25,5 C 24,5 C Yes, at room level with (easy to use) operable windows and/or ceiling fans B 26 C 24,5 C Yes, at room level with operable windows 22,5-28,5 C (-2/+4 C around s.p.) OR airspeed adjustable between 0 and 1,5 m/s 22,5-28,5 C (-2/+4 C around s.p.) OR airspeed adjustable between 0 and 1,5 m/s 23,5-27,5 C ( -1/+3 C around s.p.) OR airspeed adjustable between 0 and 0,4 m/s C 27 C 24,5 C No - (example office work; 1,2 met; 0,5 clo)

27 Introduce a yearly performance check (like Japan) Measuring CO2 levels, formaldehyde, air temperature, lighting levels etc

28 Multi Level Performance Indication in NL Source: ISSO publication 82.4 (to be published soon)

29

30 1 EXAMPLE OF AN AND-AND BUILDING (?)

31 Renovation Ministery of Finance, The Hague (2008)

32 Some IEQ measures Ministery of Finance Double skin facade... with operable windows Climate ceiling (radiant heating and cooling) Individual control over temperature (winter and summer) Limited amount of open office space Low emission materials, easy-to-clean Easy-to-clean and easy-to-maintain ventilationsystem Extended commissioning protocol (incl. Measurements) Extended IEQ complaint procedures Extended financial penalties if requirements are not met

33 Conclusion Comfortable AND energy efficient can go hand in hand (often even life cycle cost effective) Assuming: - Creative architects (also for the invisible!) - Knowledgeable HVAC and building physics consultants that understand people (not just technology) - Visionairy principals without a carte blanche - Programs of Constraints with clear performance requirements (not just for energy use!) - User comfort feedback (and actual energy use feedback) when buildings are in use

34 ards buildings designed around people