Transcript
7/30/2019 11 Neeraj Kapoor
1/17
of 17
The Relevance of Earth Air Tunnel Heat Exchanger
(EATHE) for School Buildings
Green School Design Conference
presenter: Neeraj Kapoor
for : Sustainable Design Practices for Schools in India
Hanifl Centre for Outdoor Studies, Woodstock School, Mussoorie
date: Saturday, April 17th, 2010
Kalpakrit Sustainable Environments Pvt. Ltd.
7/30/2019 11 Neeraj Kapoor
2/17
2 of 17
Our Immediate Environment: Comfort in BuildingsAs lifestyle aspirations evolve for the middle class India, we havestarted seeing air conditioning getting installed largely as an additionalfacility. Its usually used only during certain times and that forms
the basis of a mixed mode operational approach.
Ceiling Fans
Nat. Vent. / Night Flushing
Evap. Cooling
Air Conditioning
Jan Feb Mar Apr May June July Aug Sept Oct Nov Dec
AC used for 6 hrs a day for 45 days(270 hrs a year )
Ceiling fans through out summer
Graphic & Source: Ashok Lall Architects office space comfort systems usage pattern, New Delhi
7/30/2019 11 Neeraj Kapoor
3/17
3 of 17
Changing Expectations in Thermal Comfort
Basic Cool ~ Cold ~Outright Chilly
Source: Ashok B. Lall Architects
7/30/2019 11 Neeraj Kapoor
4/17
4 of 17
Changing Means to meet Comfort ExpectationsAs India develops economically there is a rising trend toward adoptingrefrigerant based air conditioning for indoor comfort.
Ceiling Fans
Nat. Vent./ Night Flushing
Evap. Cooling
Air Conditioning
Jan Feb Mar Apr May June July Aug Sept Oct Nov Dec
Graphic & Source: Adaptation of the graphic to represent contemporary trend in Institutional Buildings in India
7/30/2019 11 Neeraj Kapoor
5/17
5 of 17
Alternatively, theres . . .The Adaptive comfort model accounts for our physiological capacitiesto adapt to a wider range of temperature and humidity conditions inreal life than those that are assumed to be the idealized limits
established by laboratory experiments or even steady state standards.
Graphic & Source: Acceptable operative temperatureranges for naturally conditioned spaces, ASHRAE 55 - 2004
Adaptive Comfort
7/30/2019 11 Neeraj Kapoor
6/17
6 of 17
Adaptive Comfort versus Steady State
Adaptive / Reasonable
Hot Dry season (RH < 60%):Not Uncomfortable at 30C.
Warm Humid season (RH = 65% to 70%):Not Uncomfortable at 28C.
Image Source: Ashok B. Lall Architects
7/30/2019 11 Neeraj Kapoor
7/17
7 of 17
Forced Air Distribution versus Natural StratificationForced Air:
12.5 - 14C
UFAD/ Stratified:
15.5 18.5C
Source: # web #
7/30/2019 11 Neeraj Kapoor
8/17
8 of 17
Temperature of earth below 4m remains relatively less variantthrough the year. This characteristic is helpful in providingpreconditioned air by passing it through tunnels, thus reducing the
cooling capacity of the primary plant equipment.
Introducing . . . Earth Air Tunnel Heat Exchanger
Each tunnel to be 90m long to handle 12000 CFMapprox. depending on 900mm wide tunnel.
Slow Speed system: Air quantity based on 6 ACH inPeak Summer and 3 ACH in Monsoon & Winter.
Displacement Ventilation for natural stratification ofair column.
Source: Kalpakrit Sustainable Environments
7/30/2019 11 Neeraj Kapoor
9/17
9 of 17
EATHE must go with Displacement Ventilation
Outside air is first cooled & then let to naturally stratify as it picks up heat.
29C to 33C
25C to 29C
21C to 24C
Source: Nirmal Gupta Consultants; Original Source: # web #
7/30/2019 11 Neeraj Kapoor
10/17
10 of 17
Relevance vis--vis Schools . . . Air Quality!
Source: # web #
7/30/2019 11 Neeraj Kapoor
11/17
11 of 17
Health
Comfort
Environmentconducive tobetterperformance
Sense ofaccomplishment,sensitivity and
ownership towardsenvironmentalinitiatives.
For Students
Source: # web #
7/30/2019 11 Neeraj Kapoor
12/17
12 of 17
Comfort & Energy Efficiency when used with . . . .
Evaporative cooler in
hot dry season
Refrigerant basedcooling hybridized tocondense water outof the air
Thermal EnergyStorage formanaging peak
loads, and differentialutility tariff structures.
Jan Feb Mar Apr May June July Aug Sept Oct Nov Dec
Graphic: Adaptation of the graphic to represent use of EATHE
EATHE
Nat. Vent./ Night
Flushing
Evap. Cooling
Air Conditioning
7/30/2019 11 Neeraj Kapoor
13/17
13 of 17
Energy Efficiency Potential
CASE 1: School, Gurgaon, NCR
Source: Kalpakrit Sustainable Environments
7/30/2019 11 Neeraj Kapoor
14/17
14 of 17
Energy Efficiency Potential
CASE 2: School, Delhi
Source: Kalpakrit Sustainable Environments
7/30/2019 11 Neeraj Kapoor
15/17
15 of 17
Operational Cost Savings Potential
CASE 1: School, Gurgaon, NCR
Source: Kalpakrit Sustainable Environments
7/30/2019 11 Neeraj Kapoor
16/17
16 of 17
Operational Costs Savings Potential
CASE 2: School, Delhi
Source: Kalpakrit Sustainable Environments
7/30/2019 11 Neeraj Kapoor
17/17
17 of 17
Laundry List of Factors Influencing Performance
Housing in the Everglades
Tunnel Material
Tunnel Diameter
Tunnel Location
Tunnel Depth
Earth Temperature
Tunnel Length
Soil Properties
THANK YOU !
top related