Buildings consume almost 40 per cent of the total power pie. And 55 per cent of this power consumed by buildings is by the HVAC (heating, ventilating, air conditioning and refrigeration) units. In such a scenario, and given the imperatives of global warming, it becomes necessary to look at ways to reduce power consumption in this sector.

The advantages of the HVAC systems mean we simply cannot do away with them but there are simple ways in which much can be done. For instance, in Germany many homes have adapted the Passive Haus standard that does away with ACs, heaters and radiators by designs. The initial costs work to 7 per cent more but 79 per cent operative energy is saved eventually.

In this regard, the ISHRAE (Indian Society of Heating, Refrigerating and Air Conditioning Engineers) is doing a lot of work. The society which has about 4,500 members promotes technological knowledge through training, lectures, etc.

“The HVAC industry in India is growing and worth $4 billion. Given the requirements from the various sectors like textile, pharma, food, etc., refrigeration is poised for tremendous growth,” says S Bhagavan, president of Ishrae Bangalore chapter.

About Rs 40,000 crore of goods perish due to lack of cold storage in the country, he notes. The other emerging need is in maintaining server room temperatures for the IT, BPO centres.

Pharmaceuticals require accurate control of ambient conditions such as temperature, humidity and air-flow levels. These environments require the installation of controls such as 'dehumidification' solutions, AHUs, etc., provided by HVAC companies, says Bhagavan.

The textile industry looks at properties like dimensions, weight, tensile strength, rigidity, elastic recovery, etc., which are influenced by ambient conditions. The right humidity is provided by HVAC companies. Food and packaging industry also requires HVAC solutions to combat factors like mold counts, viruses and bacteria that infect the food, and to increase shelf-life of the products.

He cites the example of a Nasik grape grower who could export Rs 700 crore worth of grapes from a mere 40 sq km using a low drying system.

Humidification is also an emerging area used by textiles, pharma, vegetable producers, silk industry and also by people with bronchitis who need more humidity. A de-humidifier is used in the Big B's closet to protect his clothing!

Above all, new HVAC solutions seek to address problems of 'indoor air pollution', which has become a major concern in India in the recent past. Poor ventilation systems and ineffective removal of polluted indoor air result in Sick Building Syndrome (SBS), recognised by the World Health Organisation as a disease in 1984.

Bhagavan points to a  study that was carried out in 2006 to investigate the presence of SBS at a multi-storeyed, centrally air-conditioned Airport Authority of India (AAI) building in New Delhi City. The study revealed a staggering presence of SBS symptoms such as headache (51%), lethargy (50%), and dryness in body mucous (33%). A direct co-relation between SBS and CO2 concentration was observed, thus highlighting the importance of efficient ventilation measures to monitor the IAQ (Indoor Air Quality).

So, what is being done? For one, Ishrae conducts training for graduates to update them in the latest. This is an ongoing programme and there are centres in Bangalore and Delhi to do this.

Besides, there are the innovations from Ishrae members that have meant considerable reduction in power consumption, notes Pankaj J Shah.

“The power consumption has almost been halved in AC units by technical innovations at the compressor level. So also by working on the motor and fan designs the distribution has been made more efficient. The losses are down by changing the duct design which used to see loss due to friction,” he says.

There are efforts to recover up to 90 per cent of the heat generated by the HVAC units and pump it back into the cycle. In cooling a room there is much loss in taking the cold air around but this is being addressed by proper insulation as also green materials. Motors are much more efficient today, he notes.

While many refrigerators still use the atmosphere polluting CFCs, the lifetime of the gas in refrigeration has been extended up to 16 years and more.

An Ishrae member came up with a unique cycle refrigeration where by cycling for 30 minutes, you can generate 1-2 hours of power required for attaining temperatures of 4-8 deg! An added feature with a magnetic clutch helped to cut down on the pedalling!

There are many things that can be done in a 'green' manner. All it takes is some commitment and some thinking!
JK