Health and comfort are the top most priorities in today’s fast-paced lifestyle. People want a comfortable and convenient indoor environment where they can freely relax and recharge their body. Heating, Ventilating, and Air Conditioning (HVAC) helps to maintain a pleasant indoor temperature, regardless of the unbearable temperature from the outside weather.
HVAC equipment performs cooling and/or heating for residential, commercial or industrial buildings. The HVAC system may also be responsible for providing fresh outdoor air to dilute interior airborne contaminants such as odours from occupants, volatile organic compounds (VOCs) emitted from interior furnishings, chemicals used for cleaning, etc. A properly designed system will provide a comfortable indoor environment year round when properly maintained.
In a tropical country like India with diverse climatic conditions all across the nation, Heating Ventilation Air Conditioning & Refrigeration (HVAC&R) plays an important role in maintaining indoor thermal comfort conditions. If we talk about the urban India, air-conditioning has become an integral part of people’s lives. People mindset have also been changed, twenty years back use of fans and coolers in home was quite prominent but today having an air conditioner has become a necessity due to change in lifestyle even at places like Pune and Bangalore where weather is pleasant throughout the year people are using air-conditioning. Apart from this, buying power of people (especially middle class) have also increased, which leads to the increase in the sale of air-conditioners. Rapid increase in urbanisation and rising life style will make India one of the largest air conditioner markets in next 15-20 years.
India’s cooling energy demand is projected to grow exponentially over the next few years. The aggregated nationwide growth is expected to grow 2.2 to 3 times, just in the next decade, over the 2017 baseline. This increase in cooling energy demand in the country will produce lot of challenges. It will increase the Nation’s Energy Demand, put stress on electricity grid, impact on peak load, and have adverse impact on environment by enormous increase in greenhouse gas (GHG) footprint.
HVAC&R is also responsible for the global warming and depletion of ozone layer. The refrigerants used in air conditioners, chillers and refrigerators have global warming potential and some of the refrigerants such as Chloro-FluoroCarbon (CFC) used in the past by HVAC&R industry caused ozone layer depletion. Now a days CFC is entirely banned and zero ozone- depleting substances are being used. However, these refrigerants have high global warming potential.
The Kigali Amendment is a key step in the evolution of refrigerants to mitigate their impact on the environment. This landmark agreement mandates a global reduction in the production and consumption of HFCs in CO2 equivalent. As per the obligation under Kigali amendment, HFC reductions will begin in 2018 for countries like India and reduce it to 15% of 2024-2026 levels till 2047.
To cope up these challenges, new efficient technology need to be introduced in the market. All the stakeholders need to work in synchronization. Agencies like Bureau of Energy Efficiency, Energy Efficiency Services Limited, The Energy and Resources Institute etc are working very actively in this field.
Energy-efficient buildings can play very important role in controlling this cooling energy demand. HVAC is a major part of any building system. Out of total energy consumption of a building HVAC consumes on an average 50% of electricity, depending on type of building. Using passive architecture and better materials in building construction helps in reducing the overall HVAC requirement. Building envelope plays very important role in determining the size of HAVC system in any building. For making building, more energy efficient Bureau of Energy Efficiency has launched Energy Conservation Building Code (ECBC) in 2007 and revised it in 2017 and running various programmes across the nation for implementation of ECBC in various states.
It is estimated that energy efficient technologies and other know strategies can, by 2030, result in energy and carbon saving of nearly 30%. This can avoid nearly 50 power plants of almost 500 MW capacities. Investment save due to avoidance of these power plant can be used provide wider energy access. The potential GHG savings amount to nearly 170 MT/year annually, that is, roughly equivalent to what is saved by 80 GW of solar power. This data points to the fact that efficiently managing India’s cooling energy demand is not just important for energy conservation but also a key contributor for meeting India’s sustainable development goals and its international climate change commitments under the Paris Agreement (2015) and the Kigali Amendment (2016) to the Montreal Protocol.
Importance of addressing India’s growing cooling energy demand cannot be ignored particularly when India has ratified Paris Agreement with Nationally Determined Contribution s (NDC) i.e. a 30-35% reduction in energy intensity. In addition to that Indian government has come up with newer flagship programmes like Housing for All, Indian Smart City, Power for all etc. Keeping these programmes in mind, it can be estimated that most of the ACs in India considering India’s future AC stock are yet to be bought. Hence, there is potential of capturing significant amount of energy, GHG and peak load savings by using a combination of effective policy framework and implementation of efficient HVAC&R technologies.
Considering the criticality of India’s increasing cooling demand Indian government has also taken some initiative and started developing National Cooling Action Plan (NCAP). NCAP is being developed with the help of several key stakeholders such as experts from HVAC industries, energy efficiency, alternative refrigerants and research organisations that are actively working in the field of sustainable cooling. Apart from these organisations, various ministries such ministry of power, ministry of transportation, ministry of agriculture and ministry of housing and urban affairs are collectively working with ministry of environment forest and climate change (MoEF&CC) on the development of a plan that can be easily and smoothly implemented across the country. Key areas, which will be covered under the plan, are:
• Space Cooling (or comfort cooling) in Buildings
• Cooling for Transportation Cold Chain & Refrigeration
• Air Conditioning & Refrigeration Technologies
• R&D and Production Sector (alternative refrigerants and technologies)
• Servicing Sector
• Cross-cutting Policy and Regulations
It is also important to pursue efforts such as improved building design and cool rooms to reduce the electricity demand from ACs. More research and analysis is required for assessing the use of climate specific space cooling technologies like modified evaporative ACs designed specifically for humid climates. For estimating the peak demand contribution and saving from ACs more accurately, daily and hourly variations in the space cooling demand (i.e. heat indices) should be considered.
Therefore, an important future work emerging out of this analysis is developing a methodology for estimating the impact of space cooling demand on the power system more accurately. This analysis could be performed by introducing a random variable for local weather changes, and elementary load-flow analysis.
It is high time for us to think and act, because if we don’t we will have to face many environmental issues. We all know about the consequences of global warming and ozone layer depletion. Some of them are we facing already.