March, 2012 | Volume 13 Issue 3 | Editor : Sonali Dutta Associate Editor : Nagesh Dutt| NEWSLETTER

Ashrae HeadquartersAtlanta, USA

Ashrae India ChapterNew Delhi

ASHRAE INDIA CHAPTER For the

HVAC&RIndustry.

The ASHRAE India team is out to Nepal for its annual technical cum social event TECHMANTRA 2012. Techmantra is

a 4 day residential conference with an interesting mix of Technical Presentations, Yoga & Meditation. The venue being the exotic

Hotel Shangrila, Kathmandu, Nepal ! Look out for more in the next issue !

• TECHMANTRA 2012

ASHRAE will serve as a co-organizer of the 2013 CLIMA World Congress, to be held in the historic city of Prague, from June

16-19. ASHRAE volunteer leaders will be in attendance and a social gathering of ASHRAE members will take place on the

evening of June 17th as a part of the Congress.

The deadline for submission of abstracts for paper acceptance is June 30. Visit www.clima2013.org/en/call-for-abstracts for

more information. ASHRAE member registration discounts are offered. View a PDF of the conference announcement here.

• Submit a paper for Clima 2013

Register by June 1 and save. From its strong technical program to the first-hand experiences offered by its technical tours,

the Annual Conference gives attendees opportunities for examining and discussing the latest technology. Don’t miss technical

plenary speaker Lawrence E. Jones, Ph.D., director, Regulatory Affairs, Policy & Industrial Relations at Alstom Grid Inc.,

speaking on interoperability of smart building systems and smart grid. As the industry moves toward smart building systems, the

interoperability of smart buildings and the power grid becomes paramount. Jones has over 20 years of experience in the energy

industry with expertise in power systems engineering, communications and control technologies in power grid and electricity

market operations, smart grid technologies including renewable energy integration. More information at www.ashrae.org.

• ASHRAE Annual Meeting from June 23-27, 2012

Block your dates....

ACRECONF INDIA 2012

On January 12 – 13 from across the world. US Green Building Council (USGBC)

2012, The ASHRAE Chairman Mark MacCracken shared his views on USGBC’s

INDIA CHAPTER, in experience with green buildings. In addition to other technical

association with Delhi sessions, Dr. Ajay Mathur from the Bureau of Energy Efficiency

Chapter of ISHRAE, addressed participants on Government incentives/policies.

organised the largest The conference also discussed the government’s role in realizing the

technical conference dream of Net-Zero Energy Buildings.

related to Building

Design — ACRECONF

I nd i a 2012 . The

conference was held at India Habitat Centre, New Delhi. The

conference followed the theme ‘Reviving Mother Earth through

Better Building Design’. Experts from across the world shared their

experience and knowledge to accelerate large-scale acceptance of

sustainable practices in buildings.

ACRECONF was first organized in the year 2001, when it was

attended by nearly 200 delegates with 25 technical papers. Since

then, the conference attracts wider industry participation and has

been growing rapidly. During the last conference in 2010, more

than 1,800 delegates enjoyed over 98 technical papers.

ACRECONF seeks to bring together on the same platform all

stakeholders of future energy-conscious buildings. Amongst the

associate partners of the conference were the Bureau of Energy

Efficiency (BEE), Indian Green Building Council (IGBC) and IIT

Delhi. Such a list of partners emphasizes the conference’s sharp

focus on energy efficiency and conservation.

In the words of Ashish Rakheja, Chairman ACRECONF India 2012:

“After the success of previous editions, ACRECONF India 2012 is

being organized on a larger & grander scale. Societies like ISHRAE,

ASHRAE and other like minded entities are working hard to promote

the concept of Net-Zero Energy Buildings as well as the use of

energy-efficient equipment to reduce the carbon footprint of

construction industry. Towards this end, ACRECONF is yet another

step for achieving the goal of an energy-efficient & green India,

aligned with the nation’s own goal to improve its energy efficiency.”

Five parallel sessions covering topics such as Integrated Townships,

High Performance Buildings, Tall Buildings, Hospitals, Hotels and

Data Centres, among others, were addressed by eminent speakers

Conference on ‘Reviving Mother Earth through Better Building Design’

DL Lecture on ‘Air Conditioning Systems for Tropical Humid Countries’DL programme by Mr. Chandana Dalugoda on ‘Airconditioning systems for tropical humid climates’

was held on 3rd March, 2012 at Willow, India Habitat Centre, Lodhi Road, New Delhi. The programme

was attend by 30 participants.

It is my pleasure to report on the activities During my first six months, I have visited We have many distinguished members

and events that are of interest to our four chapters and interacted with the from RAL involved at the society level.

members. This is first of my three year term leadership of these chapters. I see a great However, we have many more potential

and I am honored and privileged to serve opportunity for growth, in terms of sections candidates who can move up and become

one of the most multicultural, multi- becoming chapters and formation of new volunteers serving various society

linguistic and largest regions in terms of chapters in the near future. The potential committees. Please get in touch with me in

chapters, countries and geographical chapters are Oman in Sub Region A, case you are interested. There are several

spread. The above characteristics make Cyprus and Turkey in Sub Region B. The society positions that become available

our region very special and among the respective sub regional chairs are involved each year. This is a great opportunity for all

most challenging in the society. in this process. interested to give back to the society and

develop leadership skills.The 10th CRC 2011 at Abu Dhabi was an Our next CRC will be held in Colombo,

outstanding Chapter Regional Conference Sri Lanka from 28th to 30th September, The Chicago AHR Expo 2012 turned out

in terms of number of delegates and 2011. The Sri Lankan chapter is to be one of the biggest shows in terms of

overall scale. In all 35 motions were working hard under the leadership of number of participants and exhibitors.

tabled. Three regional adhoc Committees Mr. Chandana Dalugoda to make this an The Society’s brand new logo was also

were formed to look into the aspects of outstanding event. The venue has been launched at the Chicago winter meeting

format change in Chapter reporting arranged and the CRC action committee with a appropriate tag line “Shaping

procedure, forming Web advertisements is working on the details of the Tomorrow’s Built Environment Today”.

policy and reassessing regional structure. activities that surround the meetings and I would like to take this opportunity to The past DRCs, SRCs, Committee Chairs training sessions.recognize the services of our new and other officers were recognized for

Along with our next CRC, student webmaster Mr. N. Sivasankaran, who their services and presented with personal gathering and YEA weekend program is worked hard and put together a new gavel and citation.also being scheduled. We are liaisoning website for the region. In addition, I would

On the 10th Anniversary, special with the Society President Elect and like to thank all Regional officers, Chapter

merchandize was introduced which YEA Chair for the same. I recommend Presidents, Chapter Committee Chairs

resulted in an income of more than each chapter consider providing a travel and members-at-large for their active

$1000. A few firsts - The introduction of subsidy to students and YEA members participation and cooperation, thus

the Best Chapter History Award which to set off the personal expenses making our region stronger and more

went to the Qatar Chapter and an RAL associated with the CRC to help effective.

planning committee meeting via Web make this an affordable and highly

teleconference. successful experience.

Tea Break Lecture

From the desk of DRC-RAL

– Ashok Virmani

www.ashrae.org

ACRECONF INDIA 2012

On January 12 – 13 from across the world. US Green Building Council (USGBC)

2012, The ASHRAE Chairman Mark MacCracken shared his views on USGBC’s

INDIA CHAPTER, in experience with green buildings. In addition to other technical

association with Delhi sessions, Dr. Ajay Mathur from the Bureau of Energy Efficiency

Chapter of ISHRAE, addressed participants on Government incentives/policies.

organised the largest The conference also discussed the government’s role in realizing the

technical conference dream of Net-Zero Energy Buildings.

related to Building

Design — ACRECONF

I nd i a 2012 . The

conference was held at India Habitat Centre, New Delhi. The

conference followed the theme ‘Reviving Mother Earth through

Better Building Design’. Experts from across the world shared their

experience and knowledge to accelerate large-scale acceptance of

sustainable practices in buildings.

ACRECONF was first organized in the year 2001, when it was

attended by nearly 200 delegates with 25 technical papers. Since

then, the conference attracts wider industry participation and has

been growing rapidly. During the last conference in 2010, more

than 1,800 delegates enjoyed over 98 technical papers.

ACRECONF seeks to bring together on the same platform all

stakeholders of future energy-conscious buildings. Amongst the

associate partners of the conference were the Bureau of Energy

Efficiency (BEE), Indian Green Building Council (IGBC) and IIT

Delhi. Such a list of partners emphasizes the conference’s sharp

focus on energy efficiency and conservation.

In the words of Ashish Rakheja, Chairman ACRECONF India 2012:

“After the success of previous editions, ACRECONF India 2012 is

being organized on a larger & grander scale. Societies like ISHRAE,

ASHRAE and other like minded entities are working hard to promote

the concept of Net-Zero Energy Buildings as well as the use of

energy-efficient equipment to reduce the carbon footprint of

construction industry. Towards this end, ACRECONF is yet another

step for achieving the goal of an energy-efficient & green India,

aligned with the nation’s own goal to improve its energy efficiency.”

Five parallel sessions covering topics such as Integrated Townships,

High Performance Buildings, Tall Buildings, Hospitals, Hotels and

Data Centres, among others, were addressed by eminent speakers

Conference on ‘Reviving Mother Earth through Better Building Design’

DL Lecture on ‘Air Conditioning Systems for Tropical Humid Countries’DL programme by Mr. Chandana Dalugoda on ‘Airconditioning systems for tropical humid climates’

was held on 3rd March, 2012 at Willow, India Habitat Centre, Lodhi Road, New Delhi. The programme

was attend by 30 participants.

It is my pleasure to report on the activities During my first six months, I have visited We have many distinguished members

and events that are of interest to our four chapters and interacted with the from RAL involved at the society level.

members. This is first of my three year term leadership of these chapters. I see a great However, we have many more potential

and I am honored and privileged to serve opportunity for growth, in terms of sections candidates who can move up and become

one of the most multicultural, multi- becoming chapters and formation of new volunteers serving various society

linguistic and largest regions in terms of chapters in the near future. The potential committees. Please get in touch with me in

chapters, countries and geographical chapters are Oman in Sub Region A, case you are interested. There are several

spread. The above characteristics make Cyprus and Turkey in Sub Region B. The society positions that become available

our region very special and among the respective sub regional chairs are involved each year. This is a great opportunity for all

most challenging in the society. in this process. interested to give back to the society and

develop leadership skills.The 10th CRC 2011 at Abu Dhabi was an Our next CRC will be held in Colombo,

outstanding Chapter Regional Conference Sri Lanka from 28th to 30th September, The Chicago AHR Expo 2012 turned out

in terms of number of delegates and 2011. The Sri Lankan chapter is to be one of the biggest shows in terms of

overall scale. In all 35 motions were working hard under the leadership of number of participants and exhibitors.

tabled. Three regional adhoc Committees Mr. Chandana Dalugoda to make this an The Society’s brand new logo was also

were formed to look into the aspects of outstanding event. The venue has been launched at the Chicago winter meeting

format change in Chapter reporting arranged and the CRC action committee with a appropriate tag line “Shaping

procedure, forming Web advertisements is working on the details of the Tomorrow’s Built Environment Today”.

policy and reassessing regional structure. activities that surround the meetings and I would like to take this opportunity to The past DRCs, SRCs, Committee Chairs training sessions.recognize the services of our new and other officers were recognized for

Along with our next CRC, student webmaster Mr. N. Sivasankaran, who their services and presented with personal gathering and YEA weekend program is worked hard and put together a new gavel and citation.also being scheduled. We are liaisoning website for the region. In addition, I would

On the 10th Anniversary, special with the Society President Elect and like to thank all Regional officers, Chapter

merchandize was introduced which YEA Chair for the same. I recommend Presidents, Chapter Committee Chairs

resulted in an income of more than each chapter consider providing a travel and members-at-large for their active

$1000. A few firsts - The introduction of subsidy to students and YEA members participation and cooperation, thus

the Best Chapter History Award which to set off the personal expenses making our region stronger and more

went to the Qatar Chapter and an RAL associated with the CRC to help effective.

planning committee meeting via Web make this an affordable and highly

teleconference. successful experience.

Tea Break Lecture

From the desk of DRC-RAL

– Ashok Virmani

www.ashrae.org

Integrated Design of FacilitiesGREEN C RNER: By: Amor Kool, Ashish Rakheja & Ashish Jain – Spectral Sustainability Group

The built environment has witnessed dramatic extensive reliance on fossil fuels has adverse better implementation and better management

transformation; technology has introduced effects on the financial health of organizations. of operation and maintenance. Sustainability is

more complexities into the built facility. Moreover, the cognizance of the importance of not limited to energy consumption or

A building can be compared to a human life cycle cost of buildings and establishment of conservation. Sustainability is to provide equal

anatomy having a very sensitive and responsive relation between the consumption of electricity opportunity to all. There has to be integration of

skin, complex web of veins and arteries, different with the expenditure made on maintaining the thoughts; collaboration in people’s attitude

processes which are independent but facility is resulting in drastic changes. towards nature; coordination in thought on

collaborate to perform as a single entity. rationalizing what we did yesterday and what we The designers across the world are facing fierce Building has a heart as in electric system and are doing now; acceptance of their self being. challenges with time and capital; they are very sophisticated respiratory system as HVAC, There has to be sharing, accepting the nature in exploring various solutions to develop a building which all get controlled by brain comparable to its true form without manipulating, without facility and operate it successfully. Technologies BMS. As the different parts of human anatomy is damaging it. This integration all around such as Building Information/Integrated interrelated to each other irrespective of their suggests that we want to change and we want to Modeling (BIM) provide freedom to the individuality, building does the same thing. change in a better way because “It’s too late to designers to work on different aspects of the All the factors, components and processes work be a pessimist.”building simultaneously in an integrated independently but affect each other at every environment enabling calculation and level and require holistic design solutions. manipulation of building design according to

A building is a process which broadly involves the energy needs. The integration of all the

three stages; designing, constructing and aspects from conceptualization to operation in

operating. In an ideal world, there should be an building development process identify

integrated process which complements each responsibilities vary from design decisions to

stage throughout; but unfortunately this is not fund and maintain the facility. The accountability

the case. There are many parties involved in of building construction shifts from the

building process, from owners to project assumptions to the actual performance of the

managers, architects to the various consultants building. Therefore, an inclusion of all the

and from contractors to facility managers. participants through a single BIM process

Due to the broken route in building process provides responsibility throughout the building

there left a gap between all parties of process.

communication, coordination, collaboration “The engine of life is linkage. Everything is and implementation, which can be termed as linked. Nothing is self-sufficient. Water and air ‘credibility gap’. The credibility gap can be are inseparable, united in life and our life on further defined as the difference in design earth.” To achieve sustainability which is the expectations of energy efficiency and actual fuel need of the hour, step change improvements, consumption outcomes. The reasons for procuring clients, design and building teams, credibility gap is not because of the users and managers will all need to engage shortcomings in technique to predict an energy much more closely with achieved performance. performance measure, but because of the Better transparency between intentions and assumption often used are not well informed by outcomes will release drivers towards better what really happens in practice. Some legitimate assumptions, better predictions, better design, differences identified for credibility gap are

determined as ambiguous owner’s project

requirement, design solutions, lack of skilled

labor during construction, inadequate

commissioning procedure and lack of

information transfer to the facility manager.

The credibility gap instigate a dramatic increase

of energy consumption in facilities, which causes

the unsustainable practice of exploiting

depleting fossil fuels, manipulating precarious

ecosystems, or drawing from natural resources

at a rate which is faster than that of its

replacement. This unsustainable trend made

many agencies and organizations realize that

ASHISH JAIN AIID, MPM, FAAPM, LEED® AP (O+M), IGBC APAssistant ManagerSpectral Sustainability Group

ASHISH RAKHEJAM. Tech, IIT-DelhiChief Operating OfficerSPECTRAL

=Building Energy Assessment Professional (BEAP)

=Building Energy Modeling Professional (BEMP)

=Commissioning Process Management Professional (CPMP)

=Healthcare Facility Design Professional (HFDP)

=High-Performance Building Design Professional (HBDP)

=Operations & Performance Management Professional (OPMP)

For more info, visit

www.ashrae.org/ certification

ASHRAE Certification

Programs

AMOR KOOLMasters in Construction Management-University of Washington, Seattle, Executive – Spectral Sustainability Group

Tropical Climates and Effects on Air ConditioningPosition of the earth in its orbit around the sun creates the four seasons Although wet bulb temperature is similar in Colombo and Chennai, on earth. When all the it is dryer in Chennai than Colombo. Colombo is more humid than countries on earth any of the other countries shown. Summer temperature of Delhi is compr i se o f four 43.8 C, however RH is 36% and it is has less problems of humidity seasons; summer, than any other city shown in the table.autumn, winter, spring, When considering the sun path diagrams, tropical climates has the tropics have only almost overhead path of the sun throughout the year. Hence tropical two seasons; summer climates expose to both humidity and hot temperature problems than and monsoon. other climates.Sun will be directly Humidityoverhead Tropic of Humidity is a term expressing amount of water vapour in the air.

Relative humidity, mostly used Psychrometric term, is the ratio of the actual water vapour pressure to the saturated water vapour pressure at the same dry-bulb temperature.

RH % = Pwv / Pwvs X 100

Dew point temperature in a room is uniform throughout the room. On the other hand, varies throughout the room depending on the room temperature of the air surface location at RH is measured. During morning hours, RH is almost 100% and towards the mid-day it drops to 65% in Colombo.

Reducing the risk of moisture problems

Humid climates face condensation and mould problems than any Cancer on June 21st and Tropic of Capricorn on December 21st. other combined.So countries situated between Tropic of Cancer & Capricorn are Due to high humidity, high indoor dew point, moulds growth is known as Tropical climates or Tropics.inevitable unless indoor air kept dry so that moisture materials dry out. During December South Pole has 24 hr daylight and during June To reduce the risk of mould and bug problems, following suggestions North Pole has 24 hr daylightare given by ASHRAE;

Sun will be directly overhead Tropic of Cancer on June 21st and Tropic 1. Keep rain off the exterior walls and away from the foundation, of Capricorn on December 21st. So countries situated between Tropic

using roof over hangs & rain guttersof Cancer & Capricorn are known as Tropical climates or Tropics.2. Keep rain from leaking through joints in the exterior cladding with During December South Pole has 24 hr daylight and during June

effective flashing under and around windows, doors and all other North Pole has 24 hr daylight.wall penetrations.

Tropical countries on the world map are shown below.3. Keep rain from wetting the sheathing inside the inside the exterior

wall by installing an air gap and water barrier between the exterior cladding and the sheathing.

4. Ensure the exterior wall “dry to the interior” by using vapour permeable interior wall materials and finishes.

5. Keep indoor air dry, at all times, to avoid humidity absorption and condensation on cool surfaces.

6. Seal all air ducts, air plenums and all connections to air handlers, to limit humid air infiltration and to keep humid air from drifting into contact with cool surfaces.

7. To assess the current risk of microbial growth in a building, measure the moisture content of its materials.

‘Tropics’ are the countries situated between Tropic of Cancer & Tropic of Capricorn latitudes of the earth. Optimum humidity Range for Human comfort and HealthFigure below shows the tropical countries, where sun overhead throughout the year .

Comparison between tropics and temperate climate

Schedule below shows the different outdoor conditions of tropical climates such as Colombo and Chennai against Delhi and London.

AUTUMNALEQUINOXSEPT. 21

SUMMERSOLSTICEJUNE 21

VERNALEQUINOXMARCH 21

WINTER SOLSTICEDEC. 21

SUN

TROPIC OF

CAPRICON

LATITUDE

23½°s

0° EQUATER

DEC 21

23½

JUNE 21

TROPIC OF

CANCER

LATITUDE

23½N

0° EQUATER

SUN

Unit Colombo Chennai Delhi London

dry bulb °C 33 38.5 43.8 28.3

wet bulb °C 28 28.3 29.6 19.8

RH % 68 46 36 52

www.ashrae.org

Integrated Design of FacilitiesGREEN C RNER: By: Amor Kool, Ashish Rakheja & Ashish Jain – Spectral Sustainability Group

The built environment has witnessed dramatic extensive reliance on fossil fuels has adverse better implementation and better management

transformation; technology has introduced effects on the financial health of organizations. of operation and maintenance. Sustainability is

more complexities into the built facility. Moreover, the cognizance of the importance of not limited to energy consumption or

A building can be compared to a human life cycle cost of buildings and establishment of conservation. Sustainability is to provide equal

anatomy having a very sensitive and responsive relation between the consumption of electricity opportunity to all. There has to be integration of

skin, complex web of veins and arteries, different with the expenditure made on maintaining the thoughts; collaboration in people’s attitude

processes which are independent but facility is resulting in drastic changes. towards nature; coordination in thought on

collaborate to perform as a single entity. rationalizing what we did yesterday and what we The designers across the world are facing fierce Building has a heart as in electric system and are doing now; acceptance of their self being. challenges with time and capital; they are very sophisticated respiratory system as HVAC, There has to be sharing, accepting the nature in exploring various solutions to develop a building which all get controlled by brain comparable to its true form without manipulating, without facility and operate it successfully. Technologies BMS. As the different parts of human anatomy is damaging it. This integration all around such as Building Information/Integrated interrelated to each other irrespective of their suggests that we want to change and we want to Modeling (BIM) provide freedom to the individuality, building does the same thing. change in a better way because “It’s too late to designers to work on different aspects of the All the factors, components and processes work be a pessimist.”building simultaneously in an integrated independently but affect each other at every environment enabling calculation and level and require holistic design solutions. manipulation of building design according to

A building is a process which broadly involves the energy needs. The integration of all the

three stages; designing, constructing and aspects from conceptualization to operation in

operating. In an ideal world, there should be an building development process identify

integrated process which complements each responsibilities vary from design decisions to

stage throughout; but unfortunately this is not fund and maintain the facility. The accountability

the case. There are many parties involved in of building construction shifts from the

building process, from owners to project assumptions to the actual performance of the

managers, architects to the various consultants building. Therefore, an inclusion of all the

and from contractors to facility managers. participants through a single BIM process

Due to the broken route in building process provides responsibility throughout the building

there left a gap between all parties of process.

communication, coordination, collaboration “The engine of life is linkage. Everything is and implementation, which can be termed as linked. Nothing is self-sufficient. Water and air ‘credibility gap’. The credibility gap can be are inseparable, united in life and our life on further defined as the difference in design earth.” To achieve sustainability which is the expectations of energy efficiency and actual fuel need of the hour, step change improvements, consumption outcomes. The reasons for procuring clients, design and building teams, credibility gap is not because of the users and managers will all need to engage shortcomings in technique to predict an energy much more closely with achieved performance. performance measure, but because of the Better transparency between intentions and assumption often used are not well informed by outcomes will release drivers towards better what really happens in practice. Some legitimate assumptions, better predictions, better design, differences identified for credibility gap are

determined as ambiguous owner’s project

requirement, design solutions, lack of skilled

labor during construction, inadequate

commissioning procedure and lack of

information transfer to the facility manager.

The credibility gap instigate a dramatic increase

of energy consumption in facilities, which causes

the unsustainable practice of exploiting

depleting fossil fuels, manipulating precarious

ecosystems, or drawing from natural resources

at a rate which is faster than that of its

replacement. This unsustainable trend made

many agencies and organizations realize that

ASHISH JAIN AIID, MPM, FAAPM, LEED® AP (O+M), IGBC APAssistant ManagerSpectral Sustainability Group

ASHISH RAKHEJAM. Tech, IIT-DelhiChief Operating OfficerSPECTRAL

=Building Energy Assessment Professional (BEAP)

=Building Energy Modeling Professional (BEMP)

=Commissioning Process Management Professional (CPMP)

=Healthcare Facility Design Professional (HFDP)

=High-Performance Building Design Professional (HBDP)

=Operations & Performance Management Professional (OPMP)

For more info, visit

www.ashrae.org/ certification

ASHRAE Certification

Programs

AMOR KOOLMasters in Construction Management-University of Washington, Seattle, Executive – Spectral Sustainability Group

Tropical Climates and Effects on Air ConditioningPosition of the earth in its orbit around the sun creates the four seasons Although wet bulb temperature is similar in Colombo and Chennai, on earth. When all the it is dryer in Chennai than Colombo. Colombo is more humid than countries on earth any of the other countries shown. Summer temperature of Delhi is compr i se o f four 43.8 C, however RH is 36% and it is has less problems of humidity seasons; summer, than any other city shown in the table.autumn, winter, spring, When considering the sun path diagrams, tropical climates has the tropics have only almost overhead path of the sun throughout the year. Hence tropical two seasons; summer climates expose to both humidity and hot temperature problems than and monsoon. other climates.Sun will be directly Humidityoverhead Tropic of Humidity is a term expressing amount of water vapour in the air.

Relative humidity, mostly used Psychrometric term, is the ratio of the actual water vapour pressure to the saturated water vapour pressure at the same dry-bulb temperature.

RH % = Pwv / Pwvs X 100

Dew point temperature in a room is uniform throughout the room. On the other hand, varies throughout the room depending on the room temperature of the air surface location at RH is measured. During morning hours, RH is almost 100% and towards the mid-day it drops to 65% in Colombo.

Reducing the risk of moisture problems

Humid climates face condensation and mould problems than any Cancer on June 21st and Tropic of Capricorn on December 21st. other combined.So countries situated between Tropic of Cancer & Capricorn are Due to high humidity, high indoor dew point, moulds growth is known as Tropical climates or Tropics.inevitable unless indoor air kept dry so that moisture materials dry out. During December South Pole has 24 hr daylight and during June To reduce the risk of mould and bug problems, following suggestions North Pole has 24 hr daylightare given by ASHRAE;

Sun will be directly overhead Tropic of Cancer on June 21st and Tropic 1. Keep rain off the exterior walls and away from the foundation, of Capricorn on December 21st. So countries situated between Tropic

using roof over hangs & rain guttersof Cancer & Capricorn are known as Tropical climates or Tropics.2. Keep rain from leaking through joints in the exterior cladding with During December South Pole has 24 hr daylight and during June

effective flashing under and around windows, doors and all other North Pole has 24 hr daylight.wall penetrations.

Tropical countries on the world map are shown below.3. Keep rain from wetting the sheathing inside the inside the exterior

wall by installing an air gap and water barrier between the exterior cladding and the sheathing.

4. Ensure the exterior wall “dry to the interior” by using vapour permeable interior wall materials and finishes.

5. Keep indoor air dry, at all times, to avoid humidity absorption and condensation on cool surfaces.

6. Seal all air ducts, air plenums and all connections to air handlers, to limit humid air infiltration and to keep humid air from drifting into contact with cool surfaces.

7. To assess the current risk of microbial growth in a building, measure the moisture content of its materials.

‘Tropics’ are the countries situated between Tropic of Cancer & Tropic of Capricorn latitudes of the earth. Optimum humidity Range for Human comfort and HealthFigure below shows the tropical countries, where sun overhead throughout the year .

Comparison between tropics and temperate climate

Schedule below shows the different outdoor conditions of tropical climates such as Colombo and Chennai against Delhi and London.

AUTUMNALEQUINOXSEPT. 21

SUMMERSOLSTICEJUNE 21

VERNALEQUINOXMARCH 21

WINTER SOLSTICEDEC. 21

SUN

TROPIC OF

CAPRICON

LATITUDE

23½°s

0° EQUATER

DEC 21

23½

JUNE 21

TROPIC OF

CANCER

LATITUDE

23½N

0° EQUATER

SUN

Unit Colombo Chennai Delhi London

dry bulb °C 33 38.5 43.8 28.3

wet bulb °C 28 28.3 29.6 19.8

RH % 68 46 36 52

www.ashrae.org

All ways minimize glasses on west exposure. Design the exterior enclosure and its glazing so that the sun provides day lighting at the perimeter of the building

Some places specially between 10° latitudes from equator, high humidity prevails. 70% ~ 80% RH. Needs special attention especially coastal areas to prevent condensation. High RH% leads to Bugs, Mold & Rot. ASHRAE Standard 62; occupied space relative humidity shall be designed to be limited to 65% or less Dust and particulate matter is found increased quantities. Filtration is essential

Reducing heat load from ventilation air

In London outdoor air for ventilation does not affect the total cooling load, because their outdoor conditions are 23.8 CDB, 19.8 CWB,

Vbz = Rp.Pz + Ra.Az

Where:

Az = zone floor area:

Pz = zone population:

Rp = outdoor airflow rate required per person as determined

from Table 6-1.

Ra = outdoor airflow rate required per unit area as

determined from Table 6-1

Conclusion

Air conditioning systems for Tropical Humid climates shall address the 52%RH. However, in Colombo there will be heavy penalty for following topics in order meet with energy goals;fresh air intake load because out door conditions are 33 CDB,

1. Avoid east west glasses as much as possible28 CWB, 68% RH

Energy to cool fresh air 2. Use low-e glasses for windows with sufficient shading

Total heat absorbed Q = V x 1.20 x Äh3. Never install larger cooling equipment than necessary which

causes high humidity during off cycleEnergy required for cooling 400 L/s of fresh air for ventilation in various locations is given in the chart below. 5.8 kW is required in 4. For indoor comfort use adaptive method London, where 20.2 kW is required for same 400 L/s of fresh air

5. Use ASHRAE Standard 62.1 to calculate the ventilation air in Colombo.requirement.Hence it is evident that tropical humid climates need energy recovery

for fresh air systems. Use of Rotary Enthalpy Heat exchangers are used 6. Use demand control ventilation method to reduce the load during this for this purpose. non occupying periods.

7. Use rotary enthalpy heat exchanger to reduce ventilation loads.

8. In case of using chilled beams, ceilings or displacement ventilation

provide dedicated outdoor air units to tackle humidity loads

9. In high humidity areas, specially hotel rooms, use dual set point

thermostat to prevent condensation during un-occupied operation.

Rotary Enthalpy Heat Exchanger

Incoming fresh air at 35 CDB is cooled to 26.4 CDB by part of return air at 24 CDB, which is exhausted at 32.6 CDB.

Energy wheels with molecular sieve 3A desiccant coated on aluminium substrate can recover sensible heat and latent heat, where it controls the cross contamination as well.

ASHRAE standard 62.1, ventilation rate procedure should be used to determine the ventilation air quantity, rather than using 8 L/s.person as a check figure. This is a prescriptive procedure in which outdoor air intake rates are determined based on space type/application, occupancy level, and floor area.

The design outdoor airflow required in the breathing zone of the occupiable space or spaces in a zone, i.e., the breathing zone outdoor airflow (Vbz), shall be determined in accordance with Equation

Following figure shows the optimum zone for human comfort & health 2. Clothingin relation to humidity. Thermal comfort and thermal sensation can be predicted several ways. Relative Humilities above 60% are more liable for fungi and mites One way is using ASHRAE summer and winter comfort zones chart. growth. And also these conditions increase the possibility of having More numerical and rigorous predictions are possible by using allergic asthma on people. More importantly, bacteria growth increase PMV-PPD method.above 60% RH, which causes many health problems. PMV represent the ‘predicted mean vote’ of a large population of

Thermal comfort

people exposed to a certain environment.

The PMV equation only strictly applies to human exposed to constant conditions at a constant metabolic rate.

PMV is an index that predicts the mean value of the votes of a large group of people on a 7 point scale

Table below defines the recommended PPD & PMV range for typical applications.

ASHRAE Standard 55, Thermal environmental conditions for Human occupancy, provides guidelines for maintaining comfort conditions for people I built environment. The purpose of this standard is to specify the combinations of indoor thermal environmental factors and personal factors that will produce thermal environmental conditions acceptable to a majority of the occupants within the space.

As we live in variable external environment, heating & cooling systems area required in buildings (in conjunction with adequate ventilation) to provide satisfactory thermal conditions.

1. For the occupants of the buildingsAdaptive Comfort2. For the contents, e.g. stored equipment, machinery, furnishings etc.The fundamental assumption of the adaptive approach is expressed by the adaptive principle

“If a change occurs such as to produce discomfort, people react in ways which tend to restore their comfort”

The adaptive relationship between comfort temperature and the outdoor temperature can be used to help design comfortable buildings.

Here the indoor comfort temperature is calculated from the mean outdoor temperature and plotted on a monthly basis together with the monthly mean of the daily outdoor 55 maximum, minimum and mean air temperatures.

Such a diagram helps the designer to judge whether passive heating and/or cooling are a possibility in the climate under consideration.

The relationship between the desired indoor temperature and the range of outdoor temperatures shows whether, for instance, night cooling is likely to be a viable way to keep the building comfortable in summer, or to calculate whether passive solar heating will be enough in winter.

3. For the structure and fabric of the building itself.

Thermal comfort can be defined as the condition of mind which Effects on air conditioning in Tropical humid climates High Solar satisfaction is expressed with environment. A person’s sensation of gainwarmth is influenced by the following main physical parameters, which

Tropical countries constitute the thermal environment.

g e t s u n s h i n e 1. Air temperature throughout the 2. Mean radiant temperature year, except for

monsoon season. 3. Relative air speedVery high solar 4. Humidity l o a d s , n e e d s

Beside these environmental factors there are personal factors that special attention

affect thermal comfort;to fenestration,

1. Metabolic heat production shading, walls & roofs.

Minimize exterior glazing, install insulating low-e glass and shad it. Figure above shows a building with curtain wall have more energy every year compare to less energy with less & recess windows with low-e glass.

Chandana Dalugoda CEngManaging Partner

Chandana Dalugoda ConsultantsSri lanka+3 +2 +1 0 -1 -2 -3

Hot Warm Slightly Neutral Slightly Cool Coldwarm cool

PPD PMV Range

< 10 -0.5 < PMV < +0.5

Total heat absorbed Q = Vx 1.20 x h

Q (kW)

Colombo 20.2 5.7 0.4032

Chennai 21.1 6.0 0.4224

Delhi 23.5 6.7 0.4704

London 5.8 1.6 0.1152

Q (TR) Q (kW/p)

1. Hot, humid outdoor air enters the unit.

2. The air gives up part of its heat and moisture as it flows through the passive desiccant wheel.

3. Leaving the wheel, the ventilation air carries a much smaller heat and humidity load.

4. Relatively cool and dry exhaust air leaving the building strips heat and mois ture f rom the passive desiccant wheel.

5. The exhaust air, now warm and moist, leaves the system, exhausted to the outdoors.

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All ways minimize glasses on west exposure. Design the exterior enclosure and its glazing so that the sun provides day lighting at the perimeter of the building

Some places specially between 10° latitudes from equator, high humidity prevails. 70% ~ 80% RH. Needs special attention especially coastal areas to prevent condensation. High RH% leads to Bugs, Mold & Rot. ASHRAE Standard 62; occupied space relative humidity shall be designed to be limited to 65% or less Dust and particulate matter is found increased quantities. Filtration is essential

Reducing heat load from ventilation air

In London outdoor air for ventilation does not affect the total cooling load, because their outdoor conditions are 23.8 CDB, 19.8 CWB,

Vbz = Rp.Pz + Ra.Az

Where:

Az = zone floor area:

Pz = zone population:

Rp = outdoor airflow rate required per person as determined

from Table 6-1.

Ra = outdoor airflow rate required per unit area as

determined from Table 6-1

Conclusion

Air conditioning systems for Tropical Humid climates shall address the 52%RH. However, in Colombo there will be heavy penalty for following topics in order meet with energy goals;fresh air intake load because out door conditions are 33 CDB,

1. Avoid east west glasses as much as possible28 CWB, 68% RH

Energy to cool fresh air 2. Use low-e glasses for windows with sufficient shading

Total heat absorbed Q = V x 1.20 x Äh3. Never install larger cooling equipment than necessary which

causes high humidity during off cycleEnergy required for cooling 400 L/s of fresh air for ventilation in various locations is given in the chart below. 5.8 kW is required in 4. For indoor comfort use adaptive method London, where 20.2 kW is required for same 400 L/s of fresh air

5. Use ASHRAE Standard 62.1 to calculate the ventilation air in Colombo.requirement.Hence it is evident that tropical humid climates need energy recovery

for fresh air systems. Use of Rotary Enthalpy Heat exchangers are used 6. Use demand control ventilation method to reduce the load during this for this purpose. non occupying periods.

7. Use rotary enthalpy heat exchanger to reduce ventilation loads.

8. In case of using chilled beams, ceilings or displacement ventilation

provide dedicated outdoor air units to tackle humidity loads

9. In high humidity areas, specially hotel rooms, use dual set point

thermostat to prevent condensation during un-occupied operation.

Rotary Enthalpy Heat Exchanger

Incoming fresh air at 35 CDB is cooled to 26.4 CDB by part of return air at 24 CDB, which is exhausted at 32.6 CDB.

Energy wheels with molecular sieve 3A desiccant coated on aluminium substrate can recover sensible heat and latent heat, where it controls the cross contamination as well.

ASHRAE standard 62.1, ventilation rate procedure should be used to determine the ventilation air quantity, rather than using 8 L/s.person as a check figure. This is a prescriptive procedure in which outdoor air intake rates are determined based on space type/application, occupancy level, and floor area.

The design outdoor airflow required in the breathing zone of the occupiable space or spaces in a zone, i.e., the breathing zone outdoor airflow (Vbz), shall be determined in accordance with Equation

Following figure shows the optimum zone for human comfort & health 2. Clothingin relation to humidity. Thermal comfort and thermal sensation can be predicted several ways. Relative Humilities above 60% are more liable for fungi and mites One way is using ASHRAE summer and winter comfort zones chart. growth. And also these conditions increase the possibility of having More numerical and rigorous predictions are possible by using allergic asthma on people. More importantly, bacteria growth increase PMV-PPD method.above 60% RH, which causes many health problems. PMV represent the ‘predicted mean vote’ of a large population of

Thermal comfort

people exposed to a certain environment.

The PMV equation only strictly applies to human exposed to constant conditions at a constant metabolic rate.

PMV is an index that predicts the mean value of the votes of a large group of people on a 7 point scale

Table below defines the recommended PPD & PMV range for typical applications.

ASHRAE Standard 55, Thermal environmental conditions for Human occupancy, provides guidelines for maintaining comfort conditions for people I built environment. The purpose of this standard is to specify the combinations of indoor thermal environmental factors and personal factors that will produce thermal environmental conditions acceptable to a majority of the occupants within the space.

As we live in variable external environment, heating & cooling systems area required in buildings (in conjunction with adequate ventilation) to provide satisfactory thermal conditions.

1. For the occupants of the buildingsAdaptive Comfort2. For the contents, e.g. stored equipment, machinery, furnishings etc.The fundamental assumption of the adaptive approach is expressed by the adaptive principle

“If a change occurs such as to produce discomfort, people react in ways which tend to restore their comfort”

The adaptive relationship between comfort temperature and the outdoor temperature can be used to help design comfortable buildings.

Here the indoor comfort temperature is calculated from the mean outdoor temperature and plotted on a monthly basis together with the monthly mean of the daily outdoor 55 maximum, minimum and mean air temperatures.

Such a diagram helps the designer to judge whether passive heating and/or cooling are a possibility in the climate under consideration.

The relationship between the desired indoor temperature and the range of outdoor temperatures shows whether, for instance, night cooling is likely to be a viable way to keep the building comfortable in summer, or to calculate whether passive solar heating will be enough in winter.

3. For the structure and fabric of the building itself.

Thermal comfort can be defined as the condition of mind which Effects on air conditioning in Tropical humid climates High Solar satisfaction is expressed with environment. A person’s sensation of gainwarmth is influenced by the following main physical parameters, which

Tropical countries constitute the thermal environment.

g e t s u n s h i n e 1. Air temperature throughout the 2. Mean radiant temperature year, except for

monsoon season. 3. Relative air speedVery high solar 4. Humidity l o a d s , n e e d s

Beside these environmental factors there are personal factors that special attention

affect thermal comfort;to fenestration,

1. Metabolic heat production shading, walls & roofs.

Minimize exterior glazing, install insulating low-e glass and shad it. Figure above shows a building with curtain wall have more energy every year compare to less energy with less & recess windows with low-e glass.

Chandana Dalugoda CEngManaging Partner

Chandana Dalugoda ConsultantsSri lanka+3 +2 +1 0 -1 -2 -3

Hot Warm Slightly Neutral Slightly Cool Coldwarm cool

PPD PMV Range

< 10 -0.5 < PMV < +0.5

Total heat absorbed Q = Vx 1.20 x h

Q (kW)

Colombo 20.2 5.7 0.4032

Chennai 21.1 6.0 0.4224

Delhi 23.5 6.7 0.4704

London 5.8 1.6 0.1152

Q (TR) Q (kW/p)

1. Hot, humid outdoor air enters the unit.

2. The air gives up part of its heat and moisture as it flows through the passive desiccant wheel.

3. Leaving the wheel, the ventilation air carries a much smaller heat and humidity load.

4. Relatively cool and dry exhaust air leaving the building strips heat and mois ture f rom the passive desiccant wheel.

5. The exhaust air, now warm and moist, leaves the system, exhausted to the outdoors.

www.ashrae.org