Opinion – Ground Mount Vs. Rooftop Solar: What Works Best For Industrial Use Cases?

In India’s emerging drive toward sustainable energy, solar power stands out as the linchpin for industrial decarbonization roadmaps. Among different solar deployment options considered for the industrial sector, ground-mounted and rooftop solar installations are the most commonly considered. Both configurations have their merits; however, their adoption is determined by a few factors, including space availability, energy demand, long-term scalability, economic viability, and regulatory outlook. Industries aiming for low carbon emissions with an efficient operational strategy should weigh the advantages and disadvantages of each of the configurations before adopting one with the solar strategy.

Rooftop solar has been the most sought-after option for industrial plants, especially in urban or semi-urban areas where land is at a premium. Rooftop systems make use of otherwise idle roof space, providing a relatively speedy and cost-effective option for generating clean electricity. This option often becomes the best available for the business, depending on the medium energy requirement and structural roof strength. Rooftop solar installations are, in most cases, net metered, allowing industries to offset their electricity bills with surplus power fed back into the grid, making a pretty solid financial case for small-scale manufacturing units and warehouses operating in high-tariff zones.

The flip side is that rooftop systems have their disadvantages. The roof area available may still not be able to meet the maximum energy demands of large-scale industries. Structural limits, shading concerns, and areas occupied by HVAC systems or water tanks can affect the net effective area for solar installation. In most cases, challenging ineffective roof plans or weak load-bearing capacity can limit the maximization of output potential. Practically, for energy-intensive industries, such as steel and cement, chemicals, and textiles, rooftop solar by itself may not be able to provide a meaningful offset from their power consumption or drive long-term savings.

Ground-mounted systems for solar power offer the flexibility to scale and design that makes them a natural fit for industrial consumers with considerable energy needs. These systems are typically set up on vacant land situated adjacent to the industrial premises or distant from it through open access mechanisms. Since they do not face limitations due to area constraints or due to the integrity of the roof substrate, the ground-mounted systems can be built in optimal orientations and tilt angles to maximize performance. Additionally, these systems allow for solar tracking technologies, which could further increase the efficiency of power generation by following the generalized path of the sun during the day.

For large industrial clusters and export-oriented units targeting energy autonomy or sustainable criteria in global certifications, ground-mounted solar arrays become almost a strategic asset. Besides hedging against increasing power costs, it helps the companies fulfill their renewable purchase obligations (RPOs) and thus proceed to cut their Scope 2 emissions as per ESG mandates. With open access considerations, these assets allow electricity procurement across state lines, thereby providing economic benefits despite the project being situated far away from the consumption site. In general, though, challenges still abound in land acquisition, regulatory clearances, and interconnection with the state grid, all of which take much capital and patience.

In fact, with ground mounts, upfront capital is involved, and then there is the ongoing upkeep of the land. For industries situated in thick urban centres or export promotion zones with scant land parcels, land acquisition and its upkeep stand in their way. The remote sites of some ground-mount installations also necessitate investments in transmission infrastructure and monitoring systems to ensure reliability. This implies that ground mount is suitable for large corporations or industrial parks that have the financial muscle and scale to make long-term investments in green infrastructure.

There is, of course, no black-and-white answer to the rooftop versus ground-mounted solar decision. Many progressive industries are taking the hybrid approach, with solar rooftops to serve part of their daily load and provide back-up from ground-mount/open-access solar. Such diversification serves to enhance energy security considerations while also enhancing the financial and environmental dividends from solar investments. India’s industrial sector is sprinting forward toward being green; an informed and strategically placed decision between ground-mount and rooftop solar would greatly define the pace at which businesses can transition to clean energy.

BY Shreyas Gowda, Senior VP, Oorjan Cleantech