By Amod Anand, Co-Founder & Director, Loom Solar
India’s solar energy journey has reached a decisive point. After a decade of rapid capacity additions and significant policy interventions, the conversation is shifting from “how much solar can we deploy?” to “what kind of solar can deliver long-term, sustainable power at the right cost?” For years, crystalline silicon modules such as passivated emitter and rear cell (PERC) and Tunnel Oxide Passivated Contact (TOPCon) have formed the backbone of India’s clean energy build-out. Now, attention is turning to heterojunction technology (HJT), a high-efficiency solar innovation that combines crystalline silicon with amorphous silicon layers. HJT is technically impressive, but the more interesting question is strategic: What will drive HJT adoption in India — policy, prices, or manufacturing innovation?
The honest answer is that it will require a combination of all three, working in synergy. However, the order of influence is important. In the near term, price is the biggest determinant, followed by manufacturing innovation and policy acting as an enabling force. At present, price remains the most visible hurdle to HJT adoption. While HJT offers clear long-term advantages: higher efficiency (often above 22 per cent), no light-induced degradation, slower annual degradation rates, excellent low-light performance, and lifespans of 30 years or more — it still carries a higher upfront cost. The Indian market is exceptionally price-sensitive, and procurement decisions often pivot on cost per watt rather than lifetime energy generation. This is especially true for residential consumers and smaller commercial buyers who want predictable monthly savings rather than complex performance projections.
That said, price is not merely a barrier; it is a moving target. Global manufacturing expansion will drive price reduction over the next three to five years through economies of scale. As HJT factories increase wafer throughput, automate production, reduce silver and silicon usage, and refine deposition processes, unit costs will decrease naturally. Furthermore, new materials and production designs, such as zero busbar (0BB) wiring, thinner wafers around 90 microns, and HJT-perovskite tandem cell technology are expected to push efficiency upward while reducing material intensity. These two forces combined (higher power density and lower unit material cost) will steadily close the pricing gap between HJT and PERC/TOPCon.
Where price defines adoption timing, manufacturing innovation determines adoption feasibility. HJT’s greatest structural advantage is embedded in its manufacturing process. Traditional solar cells require furnace temperatures above 800°C for diffusion and firing. HJT cell manufacturing, by contrast, uses plasma-enhanced chemical vapour deposition at just 150–250°C. This low-temperature environment cuts energy use during fabrication by an estimated 40–60 per cent, reducing carbon emissions and enabling thinner, higher-quality wafers that are less prone to micro-cracking. Several manufacturers have published carbon footprints around 366 gCO₂e per W with internal forecasts to reduce to below 300 gCO₂e per W. These numbers matter because solar manufacturing is increasingly being evaluated not only on what power it produces but on the upstream emissions embedded in each panel.
The low-temperature foundation makes HJT uniquely positioned for India’s long-term solar ambitions. Lower embedded emissions translate to reduced lifecycle impact. Less raw material consumption reduces strain on global supply chains. Reduced thermal stress creates a platform suitable for emerging technologies such as tandem perovskite-silicon cells, which can improve module efficiency beyond 30 per cent and potentially cross 35 per cent commercially within the next decade. India is already investing in this innovation pathway through domestic research, private sector research & development, and international technology partnerships supported by climate financing.
Manufacturing innovation also includes advances in automation, quality analytics, robotics, and AI-driven inspection. Defect detection, yield optimisation, and real-time quality control using electroluminescence scanning are already improving output consistency. Smart factories reduce scrap rates, improve wafer handling, and reduce silver paste consumption: all of which lower cost per watt while improving durability. For India, which is building multiple integrated solar industrial parks, smart manufacturing is not optional; it is a necessity, because imported components are vulnerable to price fluctuation, regulatory uncertainty, and supply disruption. If price determines how fast HJT scales, and manufacturing innovation makes that scaling viable, policy provides the structural confidence to invest.
Government policy remains one of the strongest catalysts for HJT adoption in India because it ensures visibility, predictability, and market stability. Key policy tools include the production-linked incentive scheme for high-efficiency solar manufacturing, quality control orders, Bureau of Indian Standards certification requirements, and the Approved List of Models and Manufacturers (ALMM). These policies favour technologies with durable performance and low degradation rates, giving natural advantage to HJT in government procurement and institutional solar projects.
Equally important are consumer-facing policies such as PM Surya Ghar: Muft Bijli Yojana scheme, which incentivises rooftop solar installations for millions of households. Subsidies fundamentally change consumer affordability dynamics, helping newer, high-efficiency technologies become mainstream faster. The PM-KUSUM scheme achieves similar momentum for agriculture, where solar pumps replace diesel-based irrigation systems. Here too, HJT’s performance in high-temperature rural climates makes it a suitable candidate for long-term savings and reliability.
India’s renewable energy targets, including 500 GW of non-fossil fuel energy by 2030, 50 per cent renewable electricity, and net-zero emissions by 2070, ensure sustained demand for solar deployment. The Green Energy Corridor infrastructure and battery storage rollout will further support consistent deployment of high-efficiency cells. These factors collectively offer the security required for large-scale HJT investment.
The adoption question is not solely a technical or policy issue, it is also a consumer centricity and stakeholder confidence issue. Different users value different aspects of HJT:
- Homeowners value reliability, long warranty, and stable performance during heat waves.
- Commercial and industrial buyers value return of investment, lower lifecycle maintenance, and predictable output.
- Utility developers value levelised cost of electricity and land efficiency.
- Investors and ESG funds value lower carbon-embedded manufacturing pathways.
- Government and regulators value domestic capability, quality assurance, and energy security.
- Environmental and community stakeholders value reduced waste over decades.
When upfront economic hesitation is paired with multi-year performance certainty, adoption accelerates. Ultimately, price, innovation, and policy are not competing forces: they are converging levers. One on its own cannot deliver widespread market transformation. Together, they create a reinforcing cycle:
- Policy encourages factories to produce HJT modules domestically.
- Manufacturing innovation brings costs down and improves yield.
- Price parity triggers mass-market consumer demand.
The long-term winner will be the technology that achieves three qualities: credible economics, demonstrated performance, and responsible manufacturing. HJT has a significant head start in this regard because its sustainability advantage begins inside the factory, before a panel ever reaches a rooftop or solar park. Lower-temperature production, reduced energy consumption, and compatibility with future tandem technologies make HJT not only an efficiency upgrade but a logical progression for India’s next stage of solar leadership. Solar companies are now aligning with establishing their ALMM manufacturing base to build a better cohesive ecosystem, and in line with that, Loom Solar is also setting up its 1.2 GW plant in Kosi, Uttar Pradesh.
India has crossed the “scale” stage of renewable deployment. The next stage is defined by technology depth and lifecycle accountability. Solar modules must be clean when they operate and clean when they are made. HJT satisfies both expectations. The factors that will drive its adoption — price visibility, manufacturing excellence, and policy support — are already rising in parallel. When these converge, HJT will not merely be an alternative; it will be an inevitability.
