As the challenges of climate change continue to loom globally, India is prioritising a balance between ecology and economic development. This emphasis on climate resilience and energy efficiency was also highlighted by the Indian government during its G20 presidency as well as at COP28, held in 2023 in the United Arab Emirates. Interestingly, the infrastructure sector is witnessing an all-time high in construction activities as it advances towards decarbonisation. A wide range of sustainable methods and techniques are being adopted based on sector viability and potential. The use of recycled and eco-friendly construction materials and renewable energy sources, an increase in the pace of electrification, and the adoption of technological platforms have been pushing the sustainable growth of this sector.
Sustainable and alternative construction materials
The use of organic construction materials, waste materials and by-products in various infrastructure sectors helps in achieving carbon-neutral construction practices. The agencies implementing construction projects in India are taking this into consideration. The road segment is a front runner in undertaking such initiatives. To this end, the Ministry of Road Transport and Highways (MoRTH) is promoting the use of fly ash, steel slag, modified bitumen, waste plastic, crumb rubber, geosynthetics, recycled aggregates, jute and coir for the sustainable construction of roads. As of September 2023, waste plastic was being used across 23 states and union territories in the construction of bituminous roads. In a recent development, the use of plastic waste has been made mandatory for the construction of roads in Baddi, Himachal Pradesh, by the Baddi Barotiwala Nalagarh Development Authority (BBNDA). The plan is to use a formula mix tested by the BBNDA and the Central Road Research Institution. Meanwhile, another feat has been accomplished in Kerala. Up until November 2023, the state’s public works department had constructed over 15,000 km of roads, including state highways and major district roads, using around 1,600 metric tonnes of shredded plastic. It started using plastic waste in road construction back in 2017. Similarly, industrial by-products such as steel slag from steel industries are being used in concrete and asphalt mixes, reducing the need for cement and natural aggregates. On January 13, 2024, a kilometre-long road segment of the Indapur-Panvel Section of NH-66, constructed with steel slag, was inaugurated. This was a first-of-its-kind execution, and trials were started by the National Highways Authority of India early in 2023.
Airports in India are also moving towards a more sustainable approach to their operations to reduce their environmental impact. To this end, new and innovative materials, such as green steel, green cement, fiberglass, fly ash, bamboo, and recycled plastic waste, are being used. For instance, over 80 metric tonnes of plastic waste has been used in road construction at the Kempegowda International Airport in Bengaluru. The airport has also pioneered the efficient use of bamboo. Furthermore, smart activators are being used in the construction of the Jewar airport in Greater Noida to increase the binding efficiency of cementitious materials and improve the material performance. Similarly, the waste produced during tunnel construction called “tunnel muck” is being utilised in the construction of railway projects. It has been used in the construction of the Udhampur-Srinagar-Baramulla Rail Link, thereby reducing carbon emissions by up to 80 per cent.
Use of green energy and electrification
All the segments of the infrastructure sector are advancing towards the adoption of renewable energy in construction activities. In the aviation segment too, 100 per cent green energy has been adopted by 66 Indian airports such as Hyderabad, Delhi, Mumbai and Bengaluru, as of December 2023. Solar energy is being harnessed on a large scale at these airports. For instance, to fulfil its energy requirements, Hyderabad airport relies on its captive 10 MWp solar power plant and the green energy supplied by Telangana State Southern Power Distribution Company Limited. Other newly inaugurated airports such as the Veer Savarkar International Airport in Port Blair and the terminal building at Kanpur airport are also equipped with solar power plants of 500 KWp and 100 KWp respectively. Similarly, the use of green energy is being pushed in the development of ports. In May 2023, the Ministry of Ports, Shipping and Waterways (MoPSW) launched the Harit Sagar Green Port Guidelines, which outline the concept of working with nature and minimising the impact on biotic components of the harbour ecosystem. The guidelines underline the importance of clean energy in developing port capabilities for storage, handling and bunkering greener fuels such as green hydrogen, green ammonia, green methanol and ethanol.
Electrification is another technique being tapped for sustainable infrastructure development. Electric highways, powered by green energy-enabled charging infrastructure, are being planned to this end. The central government aims to develop 6,000 km of these highways over the next seven years. Under this plan, a pilot project from Sohna (Gurugram) to Jaipur will be developed. Similarly, Indian Railways has gained global recognition for its pursuit to achieve 100 per cent electrification across all rail lines. It has electrified around 40,000 km of railway tracks, as of December 2023.
Adoption of new-age technologies
New and emerging technologies as well as innovative construction practices are transforming the construction industry. For instance, the application of building information modelling (BIM) has proven effective in increasing the efficiency and accuracy of construction processes. Many airport design and construction projects such as Kempegowda Airport in Bengaluru, as well as Chennai and Guwahati airports, have used BIM to streamline their workforce, data and construction activity workflows. Similarly, the upcoming Jaipur and Navi Mumbai airports will use Trimble’s BIM software and models for efficient material use and fabrication.
Precast construction is another sustainable technique being undertaken in road and highway projects. In a bid to reduce pollution at construction sites and expedite construction, MoRTH has mandated the use of 25 per cent factory-manufactured precast concrete elements in national highway projects within a 100 km radius of the precast concrete factory. This is further supported by the National Highway Pre-cast Concrete Policy approved in May 2023. Additionally, the use of drones for field surveys and differential GPS-based LiDARs is facilitating pre-construction activities. Ports in India are also being developed and upgraded as smart ports with the integration of digital solutions. Automatic gates and drive-through container scanning systems are being built at ports to optimise the movement of truck cargo and help them become more sustainable. Drive-through container scanning systems have been set up at the Bharat Mumbai Container Terminal while automatic gates powered by optical character recognition technology have been deployed for the first time in India at the Nhava Sheva (India) Gateway Terminal.
Insights into future
The unprecedented rate of urbanisation will propel the pace of construction in the coming future. The government is focused on benchmarking eco-friendly practices by introducing new measures and promoting existing ones. To this end, the central government aims to make 90 airports carbon neutral by 2024 and specific initiatives for the reduction of greenhouse gas emissions will be explored by the Ministry of Civil Aviation. Standardisation of the Carbon Accounting and Reporting Framework for Indian airports is also being taken up to raise awareness regarding climate change mitigation. Going forward, impetus will be given to the electrification of airports. The MoPSW has also set a target of covering all 12 major ports with green hydrogen bunkering facilities by 2035 under the Harit Sagar Green Port Guidelines, 2023. Its initial focus will be on the ports of Paradip in the east, Kandla in the west and Tuticorin in the south. The new policy guidelines require ports to meet at least 60 per cent of their electricity needs through renewables by 2030, and 90 per cent by 2047.
Shubhangi Goswami
