Thursday, November 30, 2006

Open to the elements!

One of my favourite subjects when I studied Energy Engineering, was Energy Efficient Buildings. These are just buildings that are built in such a way that artificial energy requirements are minimised. This is done by designing the house such that it makes optimum use of naturally available light and air, and you need not rely on artificial lighting and cooling. The materials that you use to build the house also matters.

Actually, our ancestors knew perfectly well how to build energy efficient homes. If you walk in from the hot sweltering sun into an old house with a courtyard, your face is greeted with a cool breeze, and your feet tread upon a deliciously cool floor. Where does this coolness come in on this hot day? Just a little planning and design.

And now we have lost it. For as usual, we are aping the west. The sleek glass buildings that we see so much, that look so posh and sophisticated and appealing are perfectly suited to the western climate. The glass windows are excellent absorbers of heat, and the building is automatically heated, thus reducing their heating requirements in winter. But in a tropical climate like ours, it only serves to heat up the interiors further, which we then try to counter by pumping in precious energy to power the air conditioners. So, due to glass windows, now the air conditioners have to do the work of reducing temp from 35 deg to 24 deg, rather than 28 to 24 deg (In summer, in Bangalore). And when there are power cuts, the problem could have been solved by simply opening the windows - but ah no, the windows here cannot be opened. So you have a backup of diesel generators which results in more energy wastage.

Building such energy guzzling buildings in a place like India is almost as silly as building an igloo in a desert.

If you want an example of an Energy Efficient Building, visit the office of The Energy Research Institute in Bangalore, very near Airport Road in Domlur. They have constructed the building in such a way that artificial lighting is not necessary at all. As far as I could make out, there was no air conditioning either, and no fans. Yet, there was a lot of air movement, and a cool, pleasant atmosphere. One more specialty of this place is that this building stands next to an open drain, the smell from which hits you when you go past it. But inside the building, there is no hint of a stink. You can get an idea about how it was accomplished, here.

And building such buildings is not expensive either. You just need an architect and an engineer who know the basics. But renovation or modification of an existing building to become energy efficient can be expensive.

Even our department in our college was built with these principles. The college is situated in an extremely hot place. Even then, we did not need to switch on fans even if the temperatures outside were 30-35 deg. Only when it went to 40 deg, did we switch on the fans. As for lights, even on the cloudiest day, we haven't switched on the lights in our classrooms. In fact, I wouldn't even have known where the light switches were, had we not had special classes in the evening by a visiting professor!

To give you a slight idea of the type of construction and materials used -
1) The South and West facing walls, which experience maximum solar radiation, had no classrooms or windows, but were covered with granite, which doesn't absorb heat, instead creates a cooling effect
2) The building had a courtyard, with classrooms all around... and a courtyard is perhaps the best design to create cool breezes.
3) The walls had insulating materials between bricks, which again minimized heat absorption.
4) The floor of the terrace, again, was specially constructed such that heat is not absorbed.

There is a lot of information available on the internet too, if you are interested to look. But when reading up on principles, you should remember that the principles change with the place and latitude. What might be a perfectly good design in Australia, will be totally useless in India because the angle of the solar radiation is totally different in the two hemispheres. Similarly, even a building in Bangalore (moderate climate) will be different from one in, say, New Delhi (extreme climatic conditions). Our department building was designed for a very hot climate, so it concentrated on minimising heat absorption.

Design of a building is one step - the next step involves using energy efficient light fixtures, etc. The third step involves incorporating solar water heating, and solar photovoltaics for taking care of a part of the energy requirements of the building - all these make up an energy efficient building.

And the best part of such a building is that it is a pleasure to be in it - it creates the effect of lots of space - it looks beautiful. In fact, schools should be specially designed with these principles in mind - a lot of light and air is conducive to learning.

So, if you are going to build a house, do give this a thought, will you? :)


bru said...

a very well written, interesting and informative post. great!

JK said...

Very nice article. I am a civil engineer and I cringe everytime I see a building that is built without considering the natural surroundings. A friend of mine built a house for his parents (and himself) and they did it perfectly. Solar water heaters, perfect orientation of windows and doors to allow light and air properly, well placed plants around the house to give you extra shade in summer, etc. Everytime I visit them, it is a very nice experience. Another thing to note, energy efficient buildings "SAVE YOU MONEY". I don't think people would mind a little bit of extra green in their pockets at the end of the month. :-)

nagraj said...


a little bit of extra green in their pockets at the end of the month.

I liked the way you put it.

Shastri said...

Very good post Shruthi!
I have been to the TERI building in Bangalore and it has all the 'cool' factor of a glass building along with cool temperatures.
As you say, blindly imitating some architecture can be very bad for your comfort and pocket.
I laugh with a regret whenever I see an Indian house with a 'French' window . They usually cover it with curtains inside because it gets too sunny otherwise.
The other energy inefficient thing people do is to use sloped roofs. They work very well to absorb heat in tropics since sun shines at an angle there. Here you may mostly be heating up your roof too much.
When I build a house I am sure it will be after a lot of research on energy efficiency and natural materials!

Chaitanya said...

excellent post! me too admire environment friendly buildings.

also after reading I felt kind-of proud that our house too doesn't need any elec lighting during the day in any corner and also rarely do we need fan too! a litle energy spent in designing, by the architect, did it for us! ;-)

Veena Shivanna said...

Prof , are you a civil engg or s/w engg ? I didn't read the whole post since it sounded too technical ! Read the comments & understood that it has lot to say. Not all Informative posts are Intesting to junkies like me ;-)

Shyam said...

Oddly enough, I've been reading about energy-efficient buildings too - I work for a building surveyor so he has loads of lovely interesting books on buildings and everything to do with their construction and maintenance. It's absolutely AMAZING the things one has to take into consideration... half-baked architects or builders arent going to manage a thing.

Very well written article, Shruthi!

chitra said...

Tee step ahead - interested in being the architect to my house? ;-)

Anonymous said...

had heard about this is a toefl listening topic. an interesting one, i must admit.

but difficult to implement... isnt it?

with the BDA allotting 20x30, 30x40, 40x60, 50x80 i the proportion of 4:3:2:1. can this be achieved on smaller sites?

Can this be achived in bangalore where the ppl defy the rules to build their house upto and beyond their site boundaries and some structures dangling on the other's site.

moving further, the neighbouring houses in bangalore are invariably two storeyed nowadays. What do we do about that? would all the principles of eco-friendly building considering wind directions, sunlight.... really work?

anyways..the article was a nice reading and am sure in time to come, things would change and ppl will be more eco friendly.


Bhargav said...

That's a nice effort Shruthi!
Reading through the comments, I see many people have already implemented the ideas you have mentioned. I haven't done my bit of resarch; however, I believe there must be a solution for even the 30x40 sites in the crowded old localities of Bangalore.

Manasi said...

That's a very informative post. Thanks.
It still surprises me why people who demand and also design these new glass buildings cannot understand what it does, when a layman like me, without any engg background whatsoever can logically derive that. Its understandable for the first few buildings. But even after a couple of summers...........
Your post just brought back memories of how we used to crib in office about the heat, and a college had almost broken a windowpane trying to open it!

Anonymous said...

Shruthi, good to know that you are an 'energy expert' too!

CII has two buildings to showcase, the Institute of Quality near Bidadi and the Green Business Centre in Hyderabad. Slowly, awareness is growing.

Pradeep said...

Shruti, not very often one finds a blog post on energy efficient buildings. This struck me, and read through it carefully.

These concepts are so much more advanced in the West; partly because people are more aware and partly because local communities give more stress on such things of importance.

Recently I had a friend from Britain visiting us. He was interested in setting up a wind turbine atop his house. And he had so much faith in Bangalore giving him lot of info on this.

We have the technology, but very few of us use it. I haven't gone beyond a few solar equipment. He was telling me that the government gives concessions to people who use alternative sources of energy.

Implementing these in India at one stroke has a number of inherant difficulties. Probably we can't achieve these perfections on a large scale. But if we can in some small way make a little difference... that's much more important than not making any effort at all.

Shruthi said...

Bru, thank you so much :)

JK, absolutely - you save quite a bit in both money and energy!

Nagraj, I agree with you :)

Shastri, yeah! And french windows and sloped roofs work beautifully even in India - in hill stations ;))

Chaitanya, that's so cool! It must be a beautiful house too, right? :)

Veena, I am an energy engineer ;) And the post is far from technical - I am sure most of the people commenting here are not civil engineers - do give it a try!

Shyam, thank you! Isn't it an absolutely fascinating subject? To think that you can achieve so much with a little thought! And these kind of buildings are really picking up in the UK!

Chitra, Architect, no, but energy advisor, ahem, sure ;))

Shruthi said...

MGS, actually, with a competent architect, it isn't difficult to implement. My parents' house has been built in a 60x40 site, and though all the principles couldn't be used in building the house, due to various constraints (location, etc), it is still a house that needs a minimum of lighting, and has excellent ventilation. But yes, in congested, old localities, it will be difficult. But where will you find empty sites in such localities? :)

Bhargav, yes, like I said, a little bit of planning by an informed architect should do the trick - if not a completely energy efficient building, at least a partly efficient one?

Manasi Hmmm.. defies logic, doesn't it? :O

Raj, expert, no, enthusiast, yes :) Yeah CII does involve itself in these areas - did not know about these buildings, though - interesting!

Pradeep, well said. A little effort goes a long way - and like I said, after looking at my parents' house, which by the way, isn't a totally energy efficient house, either, lots of people have been inspired to build similar houses. And yes, awareness is much more in the west - and in India, we have all the principles, but we have forgotten them - or we need to implement them to suit urban conditions.

Rk said...

I have failed to understand the motive behind using closed glass windows covered with curtains and having light and AC during the daylight. I sit next to the window :(
You might have seen this
Global warming ideas

Anonymous said...

There are some very interesting concepts like Active Solar / Passive solar with ideas like the 'sun pipe'. It is pretty easy to have an energy efficient home if you can talk to experts at IISc and architects like Chitra Vishwanathan amongst others. If you have been to Fatehpur Sikhri, Akbar had a cool breeze inside the palace through a simple mechanism to bring in cooled air. Even today, in crowded areas/monstrous buildings on all sides, it is possible to build an energy efficient home - albeit through expert advice and planning.

ethnic builder

Shruthi said...

RK, just blind imitation, nothing else! Poor you, though! That's a nice link.. thanks!

Ethnic builder, thanks a lot. That is heartening!

Anonymous said...


Very well written, but what I read / heard, this kind of construction is going to be 20-30% higher than the regular Construction. Isn't it true?

There is one such building in Hyderabad, which is rated as second best green building in the world and now many M.N.Cs are thinking of that option..

bellur said...

excellent post, shruthi.
(remembered the ajji mane red oxide flooring plus the design which was really cool!)
thanks for this informative article.

Veena Shivanna said...

Ajji mane redoxide has lot of memories to cherish! I think in Bangalore the rent depends on this factor too.. whether they have redoxide flooring, marble or decolam etc.,! Uff.. I remember those baaDige mane redoxide floorings which used to shine when mopped well.. those days & (these days too)when my housemaid is off, I very well energised to shine up the floor.. Its really a hard task but!
Energy enggineer, shall contact your when we start architecting our home! Thanks for the post.

artnavy said...

very informative- u want to do my house- when i build one?

Viky said...

wow. great post.

sorry, spellchecker was off for a few days as office lan guys are working with never-before vim and vigour.

all blogs blocked. and this damn shift key is not working.

chitra said...

Commented on EE buildings on the earlier post.

Parallax !!

Chaltha hai

Shruthi said...

Sudhakar, no, I don't think that's right - maybe I can tell you better if you can tell me exactly what you heard - about the construction materials or the design?

Bellur, ahhh the pleasure of lying on redoxide floors during summer!

Veena, sure, I'll do my best to help ;)

Artnavy, err.. not entirely, of course!

Viky, ahhh so that's why you were missing! So are you back yet, or will it still be intermittent?

Chitra, ha ha, got that, thanks!

Sanjay M said...

wow this was a real gem of a post Shruti... am forwarding this link to a friend whos constructing his house... wish I'd read it earlier!

Sanjay M said...

Guess we could club these with ideas for the eco friendly house - it should be a fun project actually! Id set out to do it but somehow got lost on the way, my mom got just too upset and I didn thave the heart to go ahead as building a house (conventional one with a capital C) was a dream for her. Will probably still do it sometime in the future.

Viky said...

I'm back and how? *sly grin*

Shruthi said...

Sanjay, thank you! Interesting links in your post too - yes, all those aspects combined makes the real energy efficient home!

Viky, Oh, I am sure evil mind works out devious ways :O

Prasad said...

Shruthi, This is a great article..reading the comments and your responses. Am bookmarking this article.

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