By Jane Marsh
Residential and commercial photovoltaic (PV) solar panel purchases increased over the past year. In the US, federal tax incentive for renewable energy purchases expires in 2022. Customers are utilizing the credit while it lasts, saving money while shrinking their carbon footprints.
The expiration date prompted various impulse purchases. Customers now look for information regarding their new renewable energy system including what materials are used to make solar panels.
Silver is a significant PV panel material. Solar companies turn silver into a paste, loading it into each silicon wafer. When sunlight reaches a panel, silicon sets electrons free. Silver carries electricity through a current, reaching a building or battery for storage.
Recently, manufacturers limited the quantity of silver in each panel. A recent price increase in the metal caused financial struggles for solar companies. The cost of silver has risen over 70% in the past year.
Professionals predict the price to rise as the world re-opens post pandemic. The effects of the price increase are currently reflected with the use of silver in solar cells decreasing from 400 milligrams to 130 milligrams between 2007 and 2016.
Environmental scientists also predict energy output rates to increase. Without the most conductive metals, scientists struggle to advance panel efficiency. The required increase in solar efficiency poses the question: “Do solar panels need silver?”
Do Solar Panels Need Silver?
Some professionals expect silver solar cell efficiency rates to level off from where they are currently. The material’s conductive properties are necessary for energy production, making it challenging for its complete removal. When evaluating its necessity for energy production, we must examine its conductive features.
Silver is the most electricity-conducting metal on the planet. It defines the conductivity scale, holding the 100 level productivity placement, with 0 being the least efficient. The material is relatively fire-safe, too, meaning it lacks the easy ability to spark.
It’s also a light metal, allowing roofs to withstand a panel’s weight. Silver’s unique properties make it a valuable component of PV systems.
Current panel efficiency levels range between 15% and 20%, making silver a necessary factor for energy production expansion. Professionals expect technological advancements to increase the panels’ electricity outputs.
Increasing efficiency while reducing silver usage requires PV research. Scientists can use near-infrared spectroscopy to measure the reflectivity of certain materials. One company utilized this technique, evaluating quality control and material efficiency.
They found that each element affects performance in unique ways. Their researchers focused mainly on glass reflectivity, and other professionals can use the technology to study metal efficiency. With further evaluation, scientists may discover whether silver is necessary or if a similar conductor may be helpful.
We must find cost-effective solutions to support the Paris Agreement’s goals. U.S. president Joe Biden has plans to expand renewable energy sourcing from the current 2% of solar consumption. When we increase the efficiency rate and lower prices, commercial and residential solar purchases will continue to grow.
Current Solar Research
Many researchers evaluate solutions to rising silver prices and efficiency rates. Copper is a viable and cost-efficient option for solar panel conductivity. The material has similar energy-producing features, but scientists see potential complications.
Copper is challenging to use in screen printing, creating a barrier for conventional panel use. The researchers also evaluated panel reconstruction, attempting to increase efficiency rates. They remanufactured solar cells, bringing them closer together with slimmer connections, reducing necessary silver use.
Unfortunately, the reconstruction was costly, limiting its ability to increase sales. With further examination, professionals may discover a sustainable solution to silver-driven complications.
An S&P Global report stated that innovation in screen-printing processes, in which silver-containing pastes are applied to solar cells in strips, is one of the key areas where manufacturers have squeezed out silver.
The COVID-19 pandemic has sparked a continuing rise in eco-consumerism. Companies must increase the sustainability of their practices to meet consumer demands to remain competitive in the industry. They can do so by adopting PV systems.
The heightened demand may drive solar businesses’ evaluation of cost-effective solutions. Once the industry alters its silver reliance, we can utilize PV systems and meet the Paris Agreement’s goal.
The Bottom Line
In 2020, the world supply of silver was 976.2 million ounces and an estimated 1,056.3 million ounces in 2021, according to the Silver Institute. Global silver demand in 2020 was 896.1 million ounces with the 2021 estimate totalling 1,033.0 million ounces.
“We forecast a slow decline in silver demand from 2020 to 2023 as [photovoltaic, or PV] capacity added per year dips, while attempts at silver thrifting in PV panels continues at a diminished rate,” CRU Group analyst Alex Laugharne wrote in a June report.
In the early 2000s, silver demand from the solar sector barely registered, making up less than a percent of silver demand. In 2019, the photovoltaic sector accounted for 10% of total silver demand, comprising 98.7 million ounces within total demand of 991.8 million ounces, according to Metals Focus data.
According to the We Recycle Solar website, silver can use up to 6% of the total cost of building each unit of a solar panel and the average panel of approximately metres2 can use up to 20 grams of silver. As of 2018, the solar panel manufacturing industry used about 8% of the world’s annual physical silver supply.
London-based consultancy CRU explored the relationship between the demand for solar power and the market trend of silver. CRU’s study determined that as of 2018, the solar panel manufacturing industry used about 8% of the world’s annual physical silver supply
Florian Clement, group head of solar cell printing technology at Fraunhofer Institute for Solar Energy Systems ISE, a major German research group, expects the industry to be able to halve its use of silver per cell over the coming decade. “A reduction down to 50 [milligrams] per cell is still expected to be possible within the next 10 years,” Clement said.
That reduction and changes to the pace of global solar installations are key drivers in the anticipated drop in silver demand from photovoltaics, analysts with CRU Group and Metals Focus said.
Jane Marsh is the Editor-in-Chief of Environment.co and an environmental writer covering green technology, sustainability and environmental news.