Photovoltaic Silver
Also: Solar silver, PV silver, Solar-cell silver
Silver used as a conductive paste in solar cells to conduct away current, today representing the single largest industrial use of the metal.
Photovoltaic silver refers to the high-purity silver that is applied in the form of screen-printing pastes to solar cells in order to conduct away the direct current generated 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-side contact - wider collector rails (busbars) that conduct the current to the external contact.
Both structures are applied by the screen-printing process as an Ag paste and then fired (sintered) at approx. 700-900 C. This forms a mechanically firm, electrically conductive layer with very low contact resistance to the silicon emitter.
Silver consumption by 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 rear side, more complex process |
The steady reduction of the silver content per cell - a process the industry calls silver thrifting - is more than offset by simultaneously sharply rising installation volumes (over 500 GWp of new build worldwide per year, as of 2024). The Silver Institute estimates that the PV sector could account for the single largest item of industrial silver demand by the end of the decade.
Raw material and supply chain
Screen-printing pastes require silver powders of very high fineness (999 or better) and controlled particle size (1-5 um). 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) that source their silver via refineries or directly from the futures market.
Influence on the silver price
PV demand has developed into the most important structural support for the physical silver market. Because silver in solar cells is chemically bound 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 end-of-life modules (after a service life of 25-30 years) is technically possible but currently barely economically established.
Price-relevant factors for investors:
- Expansion speed of renewable energies globally
- Technology shift towards lower-silver cells (TOPCon, perovskite tandem)
- Substitution pressure from copper-based contact-paste research
- Availability of recycling silver from the growing end-of-life module pool
You can follow the live silver price and its historical development on this page. With the silver calculator the material value of any quantity of silver can be quickly determined.
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 lowers consumption per cell - a structural tension that is likely to influence the spot price over the long term.