Photovoltaic Silver
Also: Solar silver, PV silver, Solar-cell silver
Silver used as a conductive paste in solar cells to conduct current away, today the single largest industrial consumption item for the metal.
Photovoltaic silver refers to the high-purity silver that is applied to solar cells in the form of screen-printing pastes in order to conduct the generated direct current away from the semiconductor. No other metal combines electrical conductivity, adhesion to silicon and process stability at sintering temperatures in a comparable way – which is why the photovoltaic industry has established itself as the fastest-growing consumer of industrial silver.
How silver works in solar cells
The solar-cell process uses silver in two places:
- Front-side finger/busbar structure – fine conductor tracks (fingers) that collect electrons from the illuminated cell surface.
- Rear contact – wider collecting rails (busbars) that conduct the current to the external contacts.
Both structures are applied in the screen-printing process as an Ag paste and then fired (sintered) at about 700–900 °C. This forms a mechanically firm, electrically conductive layer with very low contact resistance to the silicon emitter.
Silver consumption per cell technology
| Technology | Ag per cell (approx.) | Note |
|---|---|---|
| BSF (Al back-surface field) | 120–150 mg | Older mass technology, being displaced |
| PERC (passivated emitter rear cell) | 70–100 mg | Current market standard (>80% market share) |
| TOPCon (tunnel oxide passivated contact) | 40–60 mg | Growth driver, lower Ag requirement |
| HJT (heterojunction) | 120–160 mg (low temperature) | Higher-grade Ag powder needed, no sintering |
| Back-contact cells (IBC) | 80–120 mg | Fingers on the rear, more complex process |
The steady reduction of silver content per cell – a process the industry calls silver thrifting – is more than offset by simultaneously strongly rising installation volumes (over 500 GWp of new capacity per year worldwide, as of 2024). The Silver Institute estimates that by the end of the decade the PV sector could constitute the single largest item of industrial silver demand.
Raw material and supply chain
Screen-printing pastes require silver powder of very high fineness (999 or better) and controlled particle size (1–5 µm). The paste additionally contains glass frits, organic binders and solvents. Important manufacturers of contact pastes are specialised chemical companies (including in the USA, Japan, Germany and China), which source their silver via refineries or directly from the futures market.
Influence on the silver price
PV demand has become the most significant structural support of the physical silver market. Because silver is chemically bound in solar cells and can only be recovered to a limited extent with today's methods, every newly installed solar module permanently binds silver out of the market cycle. Recycling from old modules (after 25–30 years of service life) is technically possible, but currently barely economically established.
Price-relevant factors for investors:
- Global expansion speed of renewable energies
- Technology shift towards lower-silver cells (TOPCon, perovskite tandem)
- Substitution pressure from copper-based contact-paste research
- Availability of recycling silver from the growing pool of old modules
You can follow the current silver price as well as its historical development on this site. With the silver calculator you can quickly determine the material value of any quantity of silver.
Note: this is not investment or tax advice. Investment decisions should be made on the basis of individual advice.
In brief
Photovoltaic silver is today the most important industrial driver of global silver demand: the boom in solar installations permanently binds physical silver, while technological progress gradually reduces consumption per cell – a structural tension that is likely to influence the spot price over the long term.