Raj Rewal built the Coal India ltd. in and around 2010 to 2015 in Rajarhat, Kolkata, West Bengal. Raj Rewal, a renowned architect, was born in 1934 in Hoshiarpur, Punjab. He spent twelve years of his life living in Delhi and Shimla, after which he moved to London to pursue architecture. He attained considerable milestones in his journey forward, including working as an assistant stage manager and an associate of the Royal Institute of British Architects in London. He then returned to New Delhi in 1962 to establish his architectural firm. He didn’t stop there. He then built his second office in Tehran, Iran, in 1974. Later, in 1985, he founded the architectural research cell with Ram Sharma. In 1986, he curated the exhibition “Traditional Architecture in India” for the festival of India in Paris

Overall Philosophy 

Raj Rewal believes that poetry is carved in buildings. He has this unique talent for blending history and heritage through a contemporary lens. His work stood out amongst the conventional practices. His buildings are always ahead of one’s time and never fail to meet the needs of sustainability and rapid- urbanization. . 

Coal India Ltd. HeadQuarters by Raj Rewal - Sheet1
Coal India Ltd._©rajrewal.in
Coal India Ltd. HeadQuarters by Raj Rewal - Sheet2
top view_©rajrewal.in

Philosophy | Coal India Ltd

Raj Rewal usually has a set of beliefs and philosophies he follows while designing a structure. Coal India Ltd. is no different. He believed in architectural theory- “Buildings should respond to intricate demands of rapid urbanization, climate, and culture.” While designing Coal India Ltd., Raj Rewal has derived the design from expansive ideas. 


Raj Rewal’s ideology revolved around “Form Follows sun,” which was to reap the energy as an appropriate symbol for an association dealing with coal extraction. The design embraces the sun through photovoltaic panels in this age of global warming and carbon emission

Architect Raj Rewal, said Indians had been the first in the world to create micro-climatic zones within houses, using courtyards and fountains. “Now, we need to marry the traditional with modern science to have the ideal green buildings,” he said. Subsidies would possibly nudge people towards adopting green practices.

Coal India Ltd. HeadQuarters by Raj Rewal - Sheet3


Unlike conventional sustainable buildings, Coal India ltd. doesn’t use photovoltaic panels on the roof, instead are used in the most resourceful manner that complements its architectural aesthetics and serves as an energy-efficient component. 

In the Coal India Ltd. complex, the PV cells are inclined at 22 degrees towards the south. It is to generate maximum energy and electricity at the most affordable cost. The PV cell requirements and the office requirements are satisfied through the roof design. 

The stepped section of the structure permits green garden terraces that the PV panels shade. 

The design of the building is according to the site contours, and the proper timing of construction has minimized soil erosion. Harvesting of daylight is taken care of by passive design strategies like light wells and courtyards. 

Two office wings enclose a central courtyard that diffuses natural light to the rest of the structure, reducing the temperature by 5-7%, creating a microclimate.

Service spaces such as toilets are placed towards the east and west to create buffer spaces. 

Coal India Ltd. HeadQuarters by Raj Rewal - Sheet4
Coal India Ltd. HeadQuarters by Raj Rewal - Sheet5
Office Wings_©rajrewal.in

Energy efficient features | Coal India Ltd

The building has a built-up area of 2.75 lakh sq. ft spread over nine floors and can generate up to 140kWp electricity, meeting 12% of its power requirement. Hence, all the external lights work on the generated solar energy. 

The presence of low flow fixtures reduces the water consumption by 78% compared to the traditional case scenarios. It has also achieved a 50.17% reduction in the water requirement for landscape purposes. 

Achievement of Visual Comfort as:

  1. 82% of the living area uses natural light 
  2. The artificial lighting is ECBC energy compliant.
  3. External Shading and glazing reduce solar heat gain.

Achievement of Thermal Comfort as:

  1. AC spaces have reduced cooling load by using fly-ash brick in an envelope. 
  2. Water-cooled chiller as per ECBC.

To achieve an energy-efficient structure, low energy materials like the coffer slab, fly ash bricks, Autoclaved Aerated Concrete (ACC) blocks for reduced embodied energy, PPC for structural application, and plaster masonry and low energy materials for interior flooring are used. 

Coal India Ltd. HeadQuarters by Raj Rewal - Sheet6
solar panels inner view_©rajrewal.in

“The building’s air conditioning uses the thermal storage system in which the ice is made at night when power tariff is low and then the ice- cold water is used by the AC unit during the day, reducing the AC plant’s power consumption by 25%,” explained Susobhan Roy, Rewal’s associate and director of Acme Consultants. 

Fitted with movement daylight sensors and other controls, the smart building got a platinum rating from the Indian Green Building Council and has also received a 4 star GRIHA rating.

Indian culture places a high value on living in harmony with nature. Conventional Indian architecture has always echoed these concerns.

The design for the Coal India complex based on similar standards of energy efficiency, and its build also explores the possibility of solar energy for yielding electricity. 

Works Cited

Coal India Limited Office Building.

Coal India Ltd. Head Quarters-Kolkata- 2010- 2015 – Raj Rewal Associates. rajrewal.in/portfolio/coal-india-ltd-head-quarters/.

May 16, Subhro Niyogi / TNN /, et al. “Solar Panels Turn Coal India Building into a Visual Treat | Kolkata News – Times of India.” The Times of India, timesofindia.indiatimes.com/city/kolkata/solar-panels-turn-coal-india-building-into-a-visual-treat/articleshow/47303082.cms. Accessed 4 June 2022.


Sanvitti Shetty, an aspirant in the architecture field, has a keen interest in reading, writing, and researching. She is strongly opinionated and headstrong with her beliefs. She believes words can bring about a revolution in the field of architecture.