Going green is not costly

As a real estate developer, if you are a proponent of green technology, you don't have to spend too much exclusively for this. Selecting the right architecture and right building products may automatically meet a good fraction of your green needs. That's the message we gathered from Mr Harsh Bhutani, Managing Director, Eshanya Design & Projects (ED&P) group, New Delhi. ED&P has a joint venture with one of Asia's leading architecture and design firm, the A49 group.

Mr Bhutani, a professional architect, specialises in high-rises and real estate management. He has worked with US-based architecture and design major Skidmore, Owings & Merrill, the firm that designed the Burj Khalifa as well as many other architectural wonders in China and the US.

In an interaction with Business Line, Mr Bhutani gave a few examples of how the right building architecture and building products could help use energy and water efficiently.

GLASS CAN BE EFFICIENT

Large multi-storeyed buildings with exterior glass walls have caught up in India, especially after the advent of the IT and IT-enabled services sectors, in a big way. There have been instances of not-so-well-planned glass buildings that end up consuming high electricity for air-conditioning, as often the glass lets in too much heat.

According to Mr Bhutani, the use of glass in buildings does not always lead to high energy costs, if properly designed. “Much depends on how you orient your building, that is, what façade of the building uses glass. If you are energy conscious, then you will not put too much glass on the west façade, especially in hot places. It's the west face that gets more of the hot sun.”

That simply means that one has to study the weather in a region to decide which façade of the building should have glass. Having glass on the north side of the building, for instance, does not increase the room temperature, as that part of a building never gets the sun.

But what if the building design is such that it uses glass on all sides or on the west or the south façade? Even then, you have new types of architectural glasses that will fit the requirement, says Mr Bhutani.

There are glass panels that reflect most of the heat back and provide maximum light inside. Called low-heat glass panels, the technology used for this has been in vogue for over a decade. Then there are sandwich panels which have double-insulated glass windows to cut out the heat as well as sound.

According to Mr Bhutani, glass panels can in fact be more efficient than the traditional bricks and make for good building products.

SOLAR ENERGY

Besides becoming more energy-efficient, there is plenty of scope to tap renewable sources such as solar energy, says Mr Bhutani. But a small caveat: the cost effectiveness of this will depend on the kind of building and open space available. For instance, in a large spaced-out place such as a resort, there will be enough land to place the solar panels. The more space for putting in solar panels, the higher one can save on conventional energy consumption. So with enough space, a resort can save 30-40 per cent of energy consumption, says Mr Bhutani.

On the contrary, if you are looking at say a 50-60 storeyed building in Mumbai, built on about one acre, then the free area after providing for other amenities such as parking is limited. In that case, only the rooftop is left. But the rooftop does not provide enough space to lay sufficient solar panels to serve a large building. That means the panels may generate only 2-5 per cent of the building's energy requirement. That said, rooftops are ideal for smaller buildings or apartments with just 3-5 storeys.

INNOVATIVE WAYS

Another area that offers plenty of scope is water conservation. While most buildings now adopt rainwater harvesting, building developers in hot regions/deserts take to innovative ways.

Necessity perhaps forces them to seek solutions. Mr Bhutani cites an example of a project in the Gulf (not handled by A49) that generated its own water. This project tapped water by using a simple physical principle that says when hot air, which has more moisture than cold air rises, the moisture condenses. To achieve this, the said 20-30-storey building used a sandwich wall — two walls with a cavity in between.

A system was devised to suck the hot air from the bottom and run it through the cavity between the sandwich walls. As hot air rose, it cooled and the moisture condensed into water. This water was collected in little drains at the bottom of the cavity and was used to irrigate the entire landscape of the property.

That's all fine, but does all this entail a huge cost? Not really, says Mr Bhutani. “As far as the regular architectural design cost is concerned, it may not make for more than 2-3 per cent for, say, a Rs 500-crore project. Two, the general perception is that it is expensive to make a building green and that the initial capital expenditure will be high. But you will be surprised to know that the figure is not so high and that it will pay for itself in 5-7 years.”