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? :)