Across India, a silent transformation is underway in public buildings. From schools to transport hubs, smart technologies and sustainable retrofits are improving air quality, comfort, and energy efficiency, reshaping how millions experience everyday indoor environments.

Technology and sustainability play a role in real-time energy management. With IoT and AI powering building facilities, energy savings of up to 15 percent are now achievable, as demonstrated. Despite many public buildings being designed for efficiency, the real challenge lies in their operation and maintenance. This is where AI steps in – processing vast volumes of building data to streamline operations with minimum human intervention.

AI – the brain behind building efficiency

Echoing this view, Mr. C. Subramaniam (Subbu), Presidential Member of ISHRAE and Independent Consultant at 3S Green and SSS Consultants, emphasises that AI, when paired with BMS, becomes powerful. Data from various building systems—air handling units, chilled water systems, pumps, and occupancy sensors can be collected to optimise thermal comfort and air quality. Dashboards that display indoor temperature, humidity, and air quality index (AQI) at entrances offer reassurance to visitors and occupants. With feedback mechanisms in place, occupants can share their comfort levels, enabling AI to adjust set points for better indoor conditions.

Such a real-time, data-driven scenario holds promise for public buildings. Subbu argues that we are in a transitional phase, where traditional BMS systems are still being stabilised, but integrating AI can accelerate the shift. As more buildings adopt these intelligent systems, their affordability and accessibility will improve, paving the way for adoption.

Beyond digital solutions, physical improvements to existing infrastructure are equally important. Mr. Vikram Murthy, Director at Univac Environment Systems and India Representative of AHRI, highlights the importance of first assessing whether buildings meet the standards of a Green facility. Many older buildings, and even some new ones, suffer from air leakages or insufficient insulation. Retrofitting insulation and sealing infiltration points are simple upgrades that reduce cooling demand, hence energy saving. He also underlines the value of air motion. High-volume low-speed (HVLS) fans, already deployed in spaces like Mumbai’s Andheri station, improve thermal comfort in large spaces. In air-conditioned environments, these fans allow for higher set points, reducing the load on HVAC systems and turning non-green buildings into energy-efficient operations through simple retrofits.

Mr. Vivek Kumar, Product Manager at Trane Technologies, stresses that AI and smart controls are essential because even the best equipment may not deliver optimal results in real-world conditions. HVAC systems, being the largest energy consumers in most buildings, must be addressed finely using real-time data from a network of sensors, monitoring everything from temperature to occupancy to weather. AI allows systems to self-adjust, improving efficiency while maintaining comfort. Further, predictive maintenance capabilities reduce downtime by identifying equipment failures before they occur.

Mr. Jose Bonivento B., Business Development Manager at Sintali, London, adds that AI’s benefits depend on a combination of factors – regional climate, building type, and finance policies. In educational buildings, AI helps adapt operations to actual space usage, optimising energy use based on real-time occupancy. Whether it is smart glazing or high-performance installations, AI and BMS technologies together improve comfort. Predictive models also help avoid system degradation over time, leading to efficiency and sustainability.

The role of AI in building management is about automation. By turning data into actionable intelligence, AI helps in transitioning how buildings consume energy, respond to human needs, and adapt to changing environmental conditions. As the industry evolves, the fusion of AI, smart controls, and sustainable design will be at the juncture of a greener, smarter built environment.

Design principles

Modern equipment today is well-tested, contributing to building performance. However, efficiency must also come from architectural design. Mr. Vikram emphasises passive strategies like improved insulation, better glazing, reduced leakage, and pre-cooled fresh air to minimise heat ingress. Techniques such as displacement ventilation and underfloor cooling target only the occupied zone, improving comfort while saving energy. Outdoor elements—trees, shading, and water bodies—further improve thermal performance. Much-needed collaboration between architects and engineers is key to achieving green buildings. District cooling is also emerging as a sustainable solution for large campuses like airports, universities, and city clusters.

District cooling for urban efficiency

District cooling is a game-changing solution for urban energy efficiency in high-density zones like airports, business parks, and institutional campuses. Mr. C. Subramaniam (Subbu), Presidential Member of ISHRAE and Consultant at 3S Green, highlights the urgent need for large-scale adoption of this concept in India. Using the example of Bengaluru’s airport zone, he notes that nearly 20 hotels are emerging in the vicinity, each requiring around 1,500 tons of refrigeration. Combined with the airport’s estimated load of 10,000 tons, this compact area would demand around 40,000 tons of cooling capacity.

Currently, each building installs its independent cooling system—air-cooled or water-cooled chillers ranging from 300 to 400 tons, resulting in inefficiencies and a burden on the power infrastructure. Subbu suggests that if a centralised district cooling system is deployed at the planning stage—starting with 10,000 tons and scalable with demand—the energy consumption per ton of cooling would be lower. The burden on the electrical infrastructure would also be reduced.

District cooling works by producing chilled water at a central plant and distributing it through insulated underground pipes to multiple buildings. This approach offers better load management, improved space utilisation within buildings, reduced emissions, and lower operating costs. For systems to become a norm, Subbu believes a mindset shift is essential—chilled water should be treated like any other utility, available at the doorstep of every commercial or public building.

Right materials for sustainability

One of the challenges in sustainable building design is to select the right materials early in the process. As Mr. Jose Bonivento points out, life cycle assessment (LCA) at the design stage is critical. Drawing from global experience, he highlights that green buildings, when planned from the beginning with appropriate material choices, typically cost less than 2 percent more than conventional buildings, proving sustainability does not have to come at a high premium.

Making smart early choices – like specifying low-E coated glass or integrating shading devices—can reduce long-term energy costs and improve building performance. The emphasis, Jose says, should be on architects thinking like engineers and vice versa. This cross-functional mindset helps ensure that materials not only meet design aesthetics but also deliver on energy efficiency and durability.

However, pricing and sourcing remain practical hurdles. Factors like availability, embodied energy, and the need for structural changes should guide the decision to use regional versus imported materials. A holistic approach, where materials are chosen with performance, longevity, and environmental impact in mind, is essential to building an efficient and future-ready infrastructure.

Energy efficiency in public buildings

Transitioning public buildings into energy-efficient spaces does not always require major structural modifications. Instead, improvements can be achieved through smart retrofits and targeted upgrades. This includes integrating thermal storage systems, adopting smart controls, and replacing high-energy components such as boilers with more efficient alternatives like heat pumps or chillers.

Mr. Vivek Kumar highlights that adding Variable Frequency Drives (VFDs) to HVAC systems is one of the strategies. VFDs help optimise the operation of fans and pumps by adjusting their speed based on actual demand, leading to substantial energy savings. He emphasises the importance of conducting an energy audit before replacing equipment. Often, existing systems may be operating fine, but replacement could lead to avoidable costs.

In older buildings, equipment like pumps, cooling towers, and HVAC systems typically run at constant speeds, regardless of actual load. Rather than replacing entire systems, Vivek suggests assessing the compatibility of existing equipment with modern upgrades like VFDs. If compatible, VFDs can be added for performance and energy savings. This approach ensures less disruption, making it better for retrofitting public infrastructure with limited capacity for structural overhaul.

Future to the fore

The path to energy-efficient, climate-resilient public buildings lies in integrating thermal technologies, AI-driven controls, and sustainable design principles. Retrofitting existing infrastructure with smart systems, VFDs, high-efficiency HVAC equipment, and thermal storage enables energy savings without big structural changes. AI and BMS automation help optimise real-time operations. This ensures occupant comfort and reduced emissions. With district cooling, passive architecture, and life cycle-based material choices gaining momentum, public buildings can become instances of green transformation.

A collective push involving architects, engineers, and policy frameworks is more needed to accelerate this shift towards a sustainable and energised built environment.

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Vikram Murthy, Director, Univac Environment Systems & India Representative, AHRI

High-volume, low-speed fans offer a distinct advantage in improving thermal comfort. In air-conditioned buildings, simply enhancing air motion allows for higher temperature set points without foregoing comfort. Thus, even non-certified buildings can operate with green efficiencies.

Viral Mehta, Associate Partner, Integrated Consulting Engineering Services (EE)

The integration of artificial intelligence brings a transformation. By automating building systems and reducing human intervention, operational efficiencies can be improved and streamlined across multiple performance parameters.

C. Subramaniam (Subbu), Presidential Member, ISHRAE & Independent Consultant at 3S Green and SSS Consultants

We are entering a time where chilled water will be made available right at the doorstep of every commercial building, public or private. This pragmatic shift in mindset promotes infrastructure planning and positions us for energy efficiency.

Jose Bonivento B, Business Development Manager, Sintali, London

From smart glazing and basic design recovery to high-performance systems and green building strategies, AI-driven technologies are improving operational efficiency and comfort. These intelligent systems respond to real-time building conditions.

Vivek Kumar, Product Manager, Trane Technologies

Energy efficiency in public buildings does not always demand structural changes. With retrofitting, implementing smart controls, thermal storage integration, and upgraded components, it is possible to achieve improvements in performance and sustainability.