Projection
India is projected to be the world’s third-largest economy by 2030-31 according to Standard and Poor’s Global India. Simultaneously, India is the third largest energy consumer in the world after China and Indonesia. The demand for energy consumption is increasing daily in the country due to economic expansion, urbanization, high population, and better standard of living, etc. Due to global warming, there is an increase in Earth’s temperature by 1.1 degrees celcius, thus India is experiencing much hotter days than before and therefore an increase in demand for air conditioning.
Indian Marvels
Currently, houses, apartments, flats, even commercial buildings, etc. are just being made without any thought about energy saving. India is in a subtropical zone and therefore the summer’s last longer than other seasons. Staying inside the concrete buildings feels like living in a pressure cooker without air conditioning. Commercial buildings have become gas chambers, facilitating greenhouse gas emissions. India has pledged to have net zero CO2 emissions by 2070. The government is launching various projects, campaigns, and initiatives to achieve the target. But is that enough? Is it only the government’s duty? Where are well-educated architects, engineers, designers, urban planners, climatologists, environmentalists, social activists, researchers, etc. to lead the way forward? All the civilians have to mend their ways of using energy recklessly and ask for the revival of ancient cooling techniques. The market has to raise the demand for a proper supply of our long-lost passive cooling techniques.
For example, Rajasthan faces the extreme summer conditions in India that sometimes lead to drought. At such a place where hot air is in abundance, it is channelized into small pores with increased velocity, and then we get a breeze of cool air using Jali, known as the Venturi effect. Bernoulli’s theorem states,” Whenever air passes through a restricted area, its speed is increased, pressure is decreased and the air becomes cooler.” One such real example is Hawa Mahal (Palace of Winds) in Jaipur with 953 small jharokha windows with lattice work or jali.
Another example is Agra Fort which used water to keep it cool in the summers. The fort walls were made up of red sandstone and they were thick and hollow, acting as a bad conductor of heat. Water was filled in between the walls to keep it cool in summer and the void without water helps the fort to be warm in winter. The amazing fact is there is no seepage or dampness in the wall to date. Architects or designers should take inspiration from these marvels and let laymen understand the importance of every architectural element. As everything is not just for aesthetics.
Comfort Living
3 pillars decode comfortable living for the future and upcoming buildings namely- shading, ventilation, and insulation. All three are equally important. Shading devices such as -chajjas are placed above the windows externally to cut the direct heat in summer and allow the low-height sun to enter the space in winter. Nowadays, the concept of chajja is not used effectively, if the developers are asking the contractor to make it, it is only for the sake of it. The joints are not finished properly and this can cause water seepage in monsoon or sometimes low-quality material is used to make them. Hence, chajjas are not sturdy enough to hold the wind pressure in high-rise buildings.
For ventilation, direction plays a crucial role when the placement of windows is done. The opposite direction is ideal, that is, one window on the south wall and the other on the north for efficient air circulation. It is not ideal to place windows on the west wall due to the sun’s path that is from east to West via South. The third factor is the insulation for thermal comfort. That majorly depends upon the material used. At present, reinforced concrete cement is used in multi-story buildings for making walls as it is light and helps the high-rise building to keep the weight in balance. The walls are made extremely thin, sometimes 150 mm only. That means it will be a good conductor of heat and will increase the requirement for air conditioning inside the space. In the future, the thickness of the walls can be increased or better insulating materials can be used. Another option for insulation is to make cavity walls or hollow blocks that will reduce the heat gain by creating a void in between.
Rethinking about the future is the need of the hour or the mistakes made in the past will repeat. Learn from them. There is time to think and act at present. Ancient techniques are sustainable they make our buildings capable of enduring harsh climatic conditions and environment and also make us feel relaxed as well as comfortable when at home irrespective of the climate and geographical region.
Online sources:
Citations for websites:
Hindustan Times (2024). India to be third largest economy by 230-31. [online]. Available at: https://www.hindustantimes.com/business/india-to-be-third-largest-economy-by-2030-31-grow-6-7-per-annum-s-p-global-101726807349751.html [Accessed 6 Oct 2024].
Nithya Subramanian(2022). How we can design homes to stay cool in India increasingly in hot summers. [online]. Available at: https://scroll.in/article/1029837/in-illustrations-heres-how-we-can-design-homes-to-stay-cool-in-indias-increasingly-hot-summers. [Accessed 6 Oct 2024].
Greenubuntu Bureau (2021). Agra fort how Mughals keep it cool. [online]. Available at: http://greenubuntu.com/agra-fort-how-mughals-kept-it-cool-with-no-ac/. [Accessed 6 Oct 2024].
