Moving forward, sustaining through

ECO-FRIENDLY PRACTICES

Green architecture is not a new concept in  the real estate scenario. Conscientious builders are constantly striving to create eco-concious buildings, by conserving material and energy that go into the construction of newer landscapes.

Taking it a step further are Net-Zero buildings that will bring down operational energy needs of a building. Being highly energy efficient, they pose little or no threat to the environment. Bangalore has what it takes for this concept to gain ground and come into being.

Nirmal Ram is from Indian Society of Heating, Refrigerating, Air-conditioning Engineers (ISHRAE) and is the Chairman 2012 of ACREX 2012. ACREX is an international exhibition organised by Indian Society of Heating, Refrigerating & Air Conditioning Engineers (ISHRAE) and supported by a large number of professional societies from India and abroad. ACREX will showcase the Net Zero Energy Home/Office space at BIEC in February 2012, in an effort from ISHRAE to promote the concept of sustainable living. Nirmal Ram speaks on the feasibility of Net-Zero buildings in the city.  

The concept of Net Zero buildings is meant to be a step up from the average green building. How does that work?

Green buildings are known to be high-performance structure. Energy Conservation experts stipulate that an ideal green building is one where energy consumption is at the rate of 150 – 200 KW per annum per sq ft. The idea behind Net Zero buildings is that in the summer months, energy will be consumed from the grid as there is a need to power cooling mechanisms and the likes of it.

However, in the remaining months of the year, the building will create its own power for lighting through photo-voltaic cells, solar panels as well as special glass. In fact, there can also be solar powered ACs in use as well. We are working on the concept of ‘Net positive’, where excess energy generated can even be reverted to the grid. For example, if the building consumes 500 KW of power but generates 750 KW, the excess 250 KW can be directed back to the grid. All of this is currently on paper, but these concepts are quite practical.

Is this a feasible concept for Bangalore?

Like any other city, Bangalore holds a great deal of potential for such concepts. However, the costs involved in creating such a building can be prohibitive. Using photo-voltaic technology as well as glazing to convert and harness energy can be expensive.
What is essentially needed is support and subsidies from the government. If a person chooses to live in an energy- efficient home, he should be given tax subsidies. Only then will more  be encouraged to follow suit. This in turn will increase demand for such buildings and the cost of making them, affordable.  

Does the concept hold good for any type of building?

Net Zero buildings will work well for residential, commercial as well as corporate buildings, however, they will not work for industrial buildings as well. The simple reason being that industrial buildings basically need a lot of power for production and that demand may not efficiently be met in this manner.  

An energy efficient building is also about air quality control.

How can that be achieved?

Whether in Net Zero buildings or in energy efficient ones, the process is relatively the same. Any air conditioned space is sealed one. Outside air is brought in for air conditioning and the amount is as per standards prescribed. There are two measures for the quality of air – the amount of carbon-di-oxide i.e. 1000 parts/million. The second is volatile organic compounds or basically the pollutants that exist thanks to carpets, curtains and the like where compounds are bound to be retained. If these exceed the minimum, the building will suffer from what is known as sick building syndrome.  

In order to counter this, there has to be a change in air quantity brought in based on need. For example if an auditorium can house 1000 people but has only 500 at a given time it would be an inefficient use of air quantity if it were pumped in for a 1000 people. Instead, automatic controls installed can regulate the amount of air that goes in. The temperature of the air that comes in too needs to be regulated and for
Bangalore that stands at around 350 centigrade. The same principles too would apply for a space like that of gym, where quality air control is essential.  

One more concern when it comes to drawing outside air is the location of the building. In some location, the quality of air is further hampered thanks to excessive traffic and the like. In such cases, additional measures such as the installation of an ozone system are essential.  

Can existing buildings be converted to Net Zero buildings?

Green buildings are expected to exceed standard energy consumption levels by at least 30%. The idea is to conserve energy without compromising on quality. Therefore essentially net zero buildings will have to be made from scratch. Applying the principles to existing buildings may result in a great deal of modification which can end up being expensive. Orientation of a building is important too. In general, toilets and store rooms are located in the west and we may not find these in existing buildings.