Vernacular to Contemporary | PDEC | An ‘Adaptation’ – Part II

Last week in Part I, we introduced a Vernacular to Contemporary Adaptation – PDEC – Passive Downdraft Evaporative Cooling. A Vernacular ventilation strategy – Wind Catchers, which is being adapted to Contemporary buildings. We also looked at diagrams explaining the 3 main principles in this Adaptation.


This week we look at Pros and Cons of this technology for Contemporary use.


1) Energy Saving

a) Decrease cooling demand

Temperature Drops of upto 13oC can be achieved1. When the outdoors sizzle at close to 44oC, the indoors are at around 30oC.

Night Ventilation using PDEC towers decreases cooling demand and operating time of the primary cooling system the following day3.

b) Less Fluctuations

Indoor Temperature fluctuations of around 3-4oC can be seen over 24 hours, when the outside Temperature fluctuations are between 14-17oC1.


2) Cost/ Applicability

a) Short Payback Period

Electrical Consumption savings helped achieve payback of additional capital cost in less than 1 year for the Torrent Research Centre, Ahmedabad.1

b) Can be used in new / existing buildings with simple construction elements at relatively low cost.


3) Location

a) Applicable in areas without wind

As Air movement is created by momentum transfer from water to air and density difference; the technology can be applicable in areas without wind 4, 5.


4) Cleaner Air

a) Evaporative Cooling

The air is cleaned during the evaporative cooling process 6.


Cons –

1) Capacity

The cooling capacity maybe insufficient in certain cases, and could need conventional cooling as well 4.


2) Cost/ Applicability

a) High Water Consumption 6.

b) Short life of Water Pads


3) Climate Dependency

a) Works best in Hot & Dry Conditions

The technology maybe most effective in hot and dry conditions. However, buildings can be designed to adapt to other conditions and seasons. For example, in the Torrent Research Centre, the system operates normally in the dry season. In the monsoons, the water spray is not used, whereas in Winters, the openings to the rooms and shafts can be controlled (opened or closed) by the occupants 1, 4, 6.


sum up


How do You feel about this Vernacular ‘Adaptation’ for Contemporary Buildings?

Have you come across other such Adaptations?

What are your thoughts on the Practicality of this Technology? Let us know!


Video Source: 

The rchitecture Gazette

Music Source:

“Virtutes Instrumenti” Kevin MacLeod (
Licensed under Creative Commons: By Attribution 3.0 License


  1. A&D, ADEME, INDé (Mohan S.), Palacios D. | Case Study II: The Torrent Research Centre in Ahmedabad, by Abhikram. Architecture & Developpement.
  2. Zaveri P, Patel N. Abhikram | Projects | Torrent Research Centre, Ahmedabad.
  3. Paanchal JB, Mehta N. “A Review on Design of Passive Down Draft Evaporative Cooling in Commercial building.” 2017;3(2).
  4. Bowman, N. T., Eppel, H., Lomas, K. J., Robinson, D., and Cook, M. J. “Passive Downdraught Evaporative Cooling I. Concept and Precedents.” Indoor + built environment 9.5 (2000):284-290.
  5. Etzion, Y., Pearlmutter, D., Erell, E., and Meir, I. A. “Adaptive architecture: Integrating low-energy technologies for climate control in the desert.” Automation in construction 6.5 (1997):417-425.Ford, B. “Passive downdraught evaporative cooling: principles and practice.” Environmental Design. Architectural Research Quarterly 5, Cambridge University Press (2001) : 271-280.
  6. Givoni, B. “Performance of the Shower Cooling Tower in Different Climates.” Renewable Energy, 10, 2/3 (1997):173-178.

TAG Videos | Scoop-Channel-Reduce


Video Source | The Architecture Gazette | Sustinble Snippets

Music Source | “My Best Melody” catatau5 | Link

Data Sources |

  1. CTBUH. CapitaGreen – The Skyscraper Center. Accessed July 8, 2018.
  2. GreenA Consultants. Capitagreen:: GreenA Consultants. Accessed July 8, 2018.
  3. CapitaLand Commercial Trust. CapitaGreen | CapitaLand Commercial Trust. Accessed July 8, 2018.



CapitaGreen is a 82,000 sq.m., 43-floor skyscraper in the Central Business District of Singapore1. The Video looks at its design for Sustainable Ventilation.

45 m1 tall Wind-Catchers atop the skyscraper are oriented towards the prevailing wind direction2. Designed to scoop winds at this elevation, they channel air down a core known as the ‘Cool Void’3. Air from the cool void spreads horizontally through the levels, reducing Air-Conditioning loads.

Read the whole article here

Video Source:

The Architecture Gazette | Sustinble Snippets

Music Source:

“My Best Melody” catatau5 | Link

Data Sources:

  1. CTBUH. CapitaGreen – The Skyscraper Center. Accessed July 8, 2018.
  2. GreenA Consultants. Capitagreen:: GreenA Consultants. Accessed July 8, 2018.
  3. CapitaLand Commercial Trust. CapitaGreen | CapitaLand Commercial Trust. Accessed July 8, 2018.

What’s the ‘Zone’ Plan?

Akshay Urja

Building functions can be zoned according to ventilation strategy for effective management and energy conservation. This is seen in Akshay Urja Bhavan, New Delhi where spaces are divided into zones according to setpoints– Apex, Controlled and Passive. Only around 12% of the area is air-conditioned. Mist cooling systems are used for the Controlled and Passive zones1.

Read the whole article here

Graphic Source:

The Architecture Gazette | Sustinble Snippets

Data Source:

  1. BEE, USAID, PACE-D. Case Studies – Akshay Urja Bhawan. NZEB.

Addressing East and West Facades

Sustainable Snippets

These faces of the building are difficult to shade, as they receive low angle rays from the rising and setting sun. Common shading features such as horizontal projections, usually fail in such situations. Our 3 case-studies explain methods to address these tricky areas of the building.

Addressing East, West Facades; Graphics: Credits below
  1. Park Royal – The East, West facades are shaded using self-shading, achieved due to the E-shape projections from the Plan.
  2. CapitaGreen – Of all the vertical green on the facade, larger amount of greenery is provided on the East, West facades to shade them.
  3. Cleantech One – Sky gardens and planters on these facades help cool the labs and create pleasant breakout spaces.

Graphics : All graphics are produced as part of a team project for M.Sc. Integrated Sustainable Design at National University of Singapore (Building Semester – Stage 1 – Complex Living Systems). Group Members – Gajender Kumar Sharma, Aditi Bisen, Huang Hongbo, Zhao Yanming
Text: Aditi Bisen

E@BS 3/5: Commercial – CapitaGreen

This is Segment 3 of our Chain of posts focused on ‘Energy @ the Building Scale’.
[Extension of Part 4/5: The Red System (Energy), Singapore – Published: 28th May 2018]


cover capita
CapitaGreen in the Central Business District of Singapore [Image via GreenA Consultants, Singapore]
CapitaGreen is a 82,000 sq.m. GreenMark Platinum building. It is a 43-floor skyscraper in the Central Business District of Singapore designed by Architect – Toyo Ito (2). It is at less than 10-minutes walk, South-East from Park Royal, Pickering – our previous project under study. The Skyscraper has multiple sustainable features as elaborated below; which lead to energy savings of around 4.5 GWh /year (1).

Continue reading “E@BS 3/5: Commercial – CapitaGreen”

E@BS 2/5: Commercial – Park Royal Hotel

This is Segment 2 of our Chain of posts focused on ‘Energy @ the Building Scale’.
[Extension of Part 4/5: The Red System (Energy), Singapore – Published: 28th May 2018]

Park Royal hotel

Park Royal Hotel, Pickering, Singapore [Image via Nylon Singapore]
Park Royal at Pickering is a 7500 sq.m. Hotel in the thick of Singapore’s Central Business District, facing a now famous Hong Lim Park. The hotel has various sustainable features (elaborated below), that lead to approximately 30 per cent (f) energy savings in operation (using a conventional building of similar scale and functions as base case). Due to these features, it has received the GreenMark Platinum rating certification from Singapore’s Building Construction Authority.

Continue reading “E@BS 2/5: Commercial – Park Royal Hotel”

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