Solar panel minerals
It takes minerals to make solar panels. Some minerals are scarce. This might be an issue if we want to scale up green energy enough to replace fossil fuels.
Summary:
- Thin-film solar panel tech is not scalable enough. The earth just doesn't have enough rare minerals to be mined.
- There might be hope for scaling up some kind of "low-end" solar panel tech - perhaps crystalline silicon combined with mostly aluminium internal wiring instead of copper. The solar efficiency would be lower but maybe still worth it. [RESEARCH needed]
Below are ongoing tables of the minerals (and their quantities) involved in solar panel technologies. The 3rd column of the tables is based on a scenario involving 375,000 km^2 of solar panels globally (all suitable rooftops covered in solar panels) (which is very roughly what it would take to replace fossil fuels as an energy source).
General estimates
| Mineral | Quantity | How much of global reserves would be needed in a rooftop solar scenario |
|---|---|---|
| Copper | 4990 g/m2 [1] | 215% [2] |
| Silver | 0.82 g/m2 [3] | 62% [4] |
Thin-film technologies [5]
CdTe (Cadmium Telluride):
| Mineral | Quantity | How much of global reserves would be needed in a rooftop solar scenario |
|---|---|---|
| Cadmium | 6.3 g/m2 | 394% |
| Tellurium | 6.5 g/m2 | 12188% |
CIGS:
| Mineral | Quantity | How much of global reserves would be needed in a rooftop solar scenario |
|---|---|---|
| Selenium | 4.8 g/m2 | 2571% |
| Gallium | 0.53 g/m2 | 181% |
| Indium | 2.9 g/m2 | 41827% |
aSiGe:
| Mineral | Quantity | How much of global reserves would be needed in a rooftop solar scenario |
|---|---|---|
| Germanium | 0.44 g/m2 | 8250% |
Dye-sensitized:
| Mineral | Quantity | How much of global reserves would be needed in a rooftop solar scenario |
|---|---|---|
| Ruthenium | 0.1 g/m2 | 625% |
References
- ↑ Calculated from the statistic that there are 5.5 tons of copper for every megawatt(peak) of solar.
https://www.copper.org/environment/sustainable-energy/pdf/CDA-Solar-Infographic.pdf - ↑ Copper reserves: 870,000,000 tonnes
USGS Mineral Commodity Summaries 2021 - ↑ Grandell, Leena & Thorenz, Andrea, 2014. "Silver supply risk analysis for the solar sector," Renewable Energy, Elsevier, vol. 69(C), pages 157-165.
Quote:"This estimate is based on a very low silver content (0.82 g/m^2), which already reflects a technical approach to reduce silver consumption, such as the 'wrap through technology' or substitution of silver with copper, both of which are currently in development stage."
Note: Since the article is from 2014, maybe lower-silver options are available now. Also, the article doesn't really specify which solar panel technologies use this amount of silver. - ↑ Silver reserves: 500,000 tonnes
https://www.statista.com/statistics/1114842/global-silver-reserves/ - ↑ Materials Availability for Large-scale Thin-film Photovoltaics - Bjorn A. Andersson - First published in 2000 / Modified in 2020 - https://doi.org/10.1002/%28SICI%291099-159X%28200001%2F02%298%3A1%3C61%3A%3AAID-PIP301%3E3.0.CO%3B2-6
See also
- Energy to make solar panels - EROI or energy payback time - and its tradeoff against mineral intensity. Page is not made yet.
- Minerals - contains the data on global mineral reserves