The expansion and modernisation of electricity come with several constraints, such as land acquisition hurdles, installation challenges in highdensity areas, difficult terrains and long installation times. In light of these challenges, the power sector is witnessing the emergence of monopoles as a viable alternative.
A transmission monopole is a tall, self‑supporting steel or concrete pole that can carry long overhead power lines, and it comes with a simpler structure and smaller footprint than traditional lattice towers. Monopoles are suited for installation in congested sites, where land acquisition or environmental clearance might be a major hurdle. For example, one key design distinction is that while typical lattice tower installations require around 245 square metres of land for the base foundation, monopoles can operate on just 33 square metres of land. As per a technical paper, “Advantages of Monopole Transmission Tower with New Generation Conductor”, published in the International Journal of Advanced Research in Engineering and Technology, monopole transmission towers require less right of way (RoW), provide better aesthetic appeal and allow faster installation due to fewer components.
One of the most compelling use cases for monopoles in India is in forest and wildlife landscapes. Conventional lattice towers could lead to deforestation, habitat fragmentation, wildlife‑corridor disruption and increased bird mortality, resulting in instances such as the Great Indian Bustard Challenge. This is largely because they require wide RoW clearances and extensive land diversion burdens. By contrast, monopoles allow significantly narrower RoW by offering a 40-60 per cent reduction in the forest clearance area and an 80-90 per cent improvement in wildlife permeability. Although the upfront capital cost of monopoles is higher by 30-50 per cent, life cycle modelling shows that over a 25‑year horizon they deliver net savings due to reduced compensatory afforestation obligations, lower operations and maintenance, and avoided delays linked to land/forest clearance.
Increasing urban adoption
With increasing urbanisation, monopoles are emerging as an effective solution due to their lower land utilisation in urban layouts. In a recent example, Punjab State Power Corporation Limited is set to replace conventional towers with monopoles in Ludhiana, in order to reduce the risk of low‑hanging wires and wire entanglement with traffic and building encroachment.
Another example is the 400 kV double-circuit line between Sector 148 and Sector 123 in Noida by UP Power Transmission Company Limited. This project features a monopole transmission spanning 39.640 ckt km in a high‑density zone. Increasingly, in urban and peri‑urban environments where RoW and land use pressures are high, monopoles have been deployed by utilities to reduce footprint. For instance, Power Grid Corporation of India Limited (POWERGRID) has been installing monopoles since 2008-09 to save space and avoid the felling of trees. In 2021, POWERGRID commissioned the ±320 kV Pugalur (Tamil Nadu)-Thrissur (Kerala) voltage source converter-based high voltage direct current system, which deployed monopoles.
Additionally, thanks to smaller foundations, monopoles can be installed on highways or canals. With urban cities set to witness a higher residential power demand due to growth in electric vehicles, data centres and distributed renewable energy installations, transmission utilities need to proactively include more monopole projects in their network.
Monopole structures, when combined with dynamic line‑rating and travelling‑wave fault‑locators, allow for improved real‑time capacity utilisation and faster fault detection. They can also facilitate multiple circuits on a single slender pole by conserving RoW in dense or greenfield corridors.
Challenges and the way forward
Despite the benefits, monopoles come with several challenges. First, monopoles can cost up to 50 per cent more than traditional lattice towers. Additionally, local utilities may lack the required experience with monopole design and specifications since the standard guidelines in India are yet to mature as compared to lattice towers. Consequently, the maintenance of a monopole structure is also more challenging. When compared to lattice towers, which have a lifespan of up to 50 years, monopoles have a lifespan of 30 years and a lower recycling value.
While these factors may significantly affect the project economics of a monopole compared to a lattice tower, we must look at their installation from the dual context of rapid grid expansion as well as improved efficiency and lower social and environmental costs. For utilities and policymakers, it is important to recognise monopoles as a strategic complement to existing tower systems. With the right regulatory and policy support, monopoles could become an important component of India’s strategy to modernise the grid.
