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Solar manufacturers in China are facing a materials inflection point as silver costs challenge long-standing cell designs.
Ni Tao is IE’s columnist, giving exclusive insight into China’s technology and engineering ecosystem. His monthly Inside China column explores the issues that shape discussions and understanding about Chinese innovation, providing fresh perspectives not found elsewhere.
As silver prices surge to multi-year highs, hitting $75 per ounce as of January 5, 2026, shockwaves are rippling through China’s solar manufacturing heartland.
For an industry already operating on thin gross margins, estimated at around 10 percent in 2025, the rising cost of its most critical precious metal has exacerbated an old anxiety: how long can photovoltaic (PV) cell makers afford to rely on silver to collect the sun’s power?
At the center of this cost squeeze lies the metallization step of solar cell production — the process of forming ultra-fine conductive grid lines on the front and back of a silicon wafer to collect and transport electricity.
These grid lines must strike a delicate balance: they need to conduct current efficiently, adhere tightly to silicon, minimize electrical losses and shading, and above all, cost as little as possible. For decades, silver among metals has met most of these requirements.
Today, its rising price is forcing the industry to rethink that dependence. PV engineers worldwide are racing to develop cheaper yet equally effective alternatives. Nowhere is this pressure more acute than in China, whose solar module manufacturers account for roughly 80 percent of global production capacity.
Within a solar panel, photons generate charge carriers inside silicon, but without an efficient collection network, much of that energy would go to waste. The metallization layer — typically composed of thin “fingers” and thicker “busbars” — serves as the cell’s electrical highway.
Inside a solar cell, photons generate charge carriers within silicon. Without an efficient collection network, much of that energy would be lost. The metallization layer—typically composed of thin “fingers” and thicker “busbars”—acts as the cell’s electrical highway.
Ideally, these lines should be highly conductive, form low-resistance ohmic contact with silicon, and be as narrow and tall as possible to reduce light shading while maintaining current capacity.
Silver has long been the material of choice because of its excellent conductivity and stable contact properties. Yet it is also the single largest non-silicon cost item in a cell, representing roughly 30-50 percent of non-silicon costs. As silver prices skyrocket, reducing or eliminating its use has become one of the industry’s most urgent technological quests.
The dominant solution today remains traditional silver paste, used across mainstream cell architectures such as PERC, TOPCon, and HBC. The paste — a mixture of micron-sized silver powder, glass frit, and organic binders — is screen-printed onto the wafer and then fired at temperatures up to 700 degrees Celsius.
During firing, the glass frit melts and etches through the silicon nitride anti-reflection layer, allowing silver to alloy with silicon and form an ohmic contact. In the meantime, silver particles sinter into a conductive network as part of a robust and highly scalable process.
Beyond exposure to soaring silver prices, this technology is approaching physical limits: making grid lines thinner to save silver increases resistance, while screen printing struggles to achieve the ultra-high aspect ratios needed for efficiency gains in next-gen cells.
To cut costs without overhauling production lines, manufacturers in China have steadily turned to silver-coated copper paste — a transitional technology designed to partially replace pure silver.
Under this method, copper particles form the core, coated with a dense silver shell that guards against oxidation. The resulting paste can be printed and sintered using processes largely compatible with existing lines, though typically at lower temperatures (below 200 degrees) to avoid damaging the silver shell.
In theory, this approach can reduce silver usage by 30-50 percent. But in practice, it comes with new technical challenges. The integrity of the silver coating is critical: any exposure of copper can lead to oxidation, conductivity loss, and long-term reliability risks. Therefore, finished products are commonly subject to strict testing, such as PID or DH2000. Process control also becomes tighter, and the firing “window” is narrower.
Despite these concerns, silver-coated copper has already entered mass production in China and is primarily applied to the rear side of cells, where performance requirements are less stringent.
Leading manufacturers like Longi and Jinko are now cautiously testing it on front-side grids across a suite of their HJT, TOPCon, and HBC panels. In the short term, silver-coated copper is widely seen as the most practical and immediate response to the silver price spike.
A more radical idea is to eliminate silver entirely by using pure copper paste. Copper is cheap, abundant, and highly conductive — but also chemically troublesome. It oxidizes readily and, more critically, diffuses into silicon, where it forms deep defects, such as recombination centers. It traps carriers and accelerates electron-hole recombination, reducing carrier lifetime and degrading cell performance.
Overcoming these issues requires additional layers between copper and silicon, such as nickel, titanium, or zinc oxide, to block diffusion and enable proper electrical contact. Besides, firing must occur in strictly controlled inert or reducing atmospheres to prevent oxidation.
The result is a much more complex workflow, often requiring new deposition equipment and environments incompatible with current production lines. For now, pure copper paste remains largely confined to laboratories and early-stage R&D, with large-scale commercialization still a distant prospect.
Technically, low-temperature sintering under inert atmospheres improves compatibility and reduces thermal damage. But high-temperature TOPCon cells still rely on silver seed layers, while the commercialization of pure copper paste depends on advances in precision fabrication and nanoscale interconnection.
The most revolutionary — and potentially transformative — solution is electroplated copper metallization. Instead of printing and firing metal paste, this approach borrows techniques from the semiconductor industry, relying on thin seed layers, precise patterning, and electrochemical deposition.
In a typical process for heterojunction (HJT) cells, a nanometer-scale seed layer of copper or nickel is first deposited through physical vapor deposition. The grid pattern is then printed via photolithography or emerging, lower-cost alternatives, such as laser patterning. The third step is to electroplate copper onto the exposed seed areas, building tall, narrow grid lines with exceptional aspect ratios.
The advantages are compelling: zero silver consumption, superior conductivity, ultra-low shading losses, and a low-temperature process well suited to HJT and perovskite tandem cells. The drawbacks are equally stark — complex workflows, high equipment costs, wet-chemical handling, and stringent contamination control, as copper ions can be fatal to silicon devices if mismanaged.
Even so, momentum is building. Multiple Chinese and international players have established pilot lines, racing to cut patterning costs and simplify processes. Within the industry, electroplated copper is increasingly viewed as the most promising long-term consolation for “silver anxiety.”
The trajectory is becoming clearer, with PV metallization following a well-defined roadmap in China. In the short term (one to three years), silver-coated copper pastes are expected to see growing adoption as the market’s dominant cost-reduction solution, enabling manufacturers to rapidly substitute copper for silver while preserving reliability.
Over the medium term (three to five years), electroplated copper is likely to redefine metallization for advanced cell architectures such as HJT and back-contact designs, where efficiency gains and low-temperature processing are critical.
As pilot lines transition toward mass production, electroplated copper is increasingly viewed as a next-gen technology platform with the potential to drive improvements in cell efficiency.
In the long term, electroplated copper — or more advanced technologies — could become the mainstream solution, particularly as they co-evolve with new cell structures such as perovskite tandems, opening up additional efficiency headroom.
Pure copper paste, although now a long shot, may remain a viable option if reliability challenges are eventually overcome.
Ultimately, all metallization pathways are converging on the same objective: achieving the lowest possible levelized cost of electricity (LCOE) while ensuring steady, stable operation over the 25-year-plus lifetime of a PV power plant. In China, laws stipulate that solar farms have a designed lifespan of at least 25 years.
Which technology prevails will depend not on a single breakthrough, but on how PV manufacturers align their product strategies, technical foundations, and cost-control capabilities.
As the silver rally continues into 2026, putting greater pressure on industrial settings such as PV production, electronics manufacturing and energy storage, China’s solar manufacturers are learning a hard lesson in precious metals dependence: the proper response is never a single disruptive leap, but a layered transition that could turn today’s cost pressure into a catalyst for the next phase of innovation.
Ni Tao worked with state-owned Chinese media for over a decade before he decided to quit and venture down the rabbit hole of mass communication and part-time teaching. Toward the end of his stint as a journalist, he developed a keen interest in China's booming tech ecosystem. Since then, he has been an avid follower of news from sectors like robotics, AI, autonomous driving, intelligent hardware, and eVTOL. When he's not writing, you can expect him to be on his beloved Yanagisawa saxophones, trying to play some jazz riffs, often in vain and occasionally against the protests of an angry neighbor.
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