Terry Knowles, European Editor06.28.23
In my columns in Ink World and Coatings World, there is inevitably a frequent focus on the green ambitions held by the EU. Wouldn't it be a great thing if solar power could play an even greater part in achieving the EU's long-term goals?
Solar ink is not quite new but recent developments have been instrumental in advancing what can be achieved with printable solar cells. For the most part, this article looks at what the developments are in this area and what can be achieved.
The technology works around the production of thin yet flexible solar panels, and that in itself overcomes the limitations of fixed solar cell panels, which despite being seen as eco-friendly are energy-intensive to produce and fragile to handle.
Industry is also in a position where the requirements for producing traditional solar cells on the scale of 21st-century demand means that the materials needed for their manufacture will be depleted by the mid-century.
Recent advances in Europe have witnessed the emergence of solar cells that are both printable and rollable. Their production in laboratories has been developed under special conditions where water and oxygen are removed, furnishing cells that have an operational efficiency that matches the conventional solar cell.
Manufacturing these analogously in industry would be potentially very costly but aiming to print the cells on plastic film thwarts that particular challenge. Researchers at the University of Swansea have hence pioneered a technique for the on-film printing of perovskite solar cells using a carbon ink in conjunction with the slot-die coating process (a technique used for the production of photographic films).
One of the requirements for this been the development of perovskite and semiconductor layers that have thicknesses of 50 – 500 nm within the cell. Years of research have also delivered a process that eliminates the use of highly toxic solvents for solar cell production.
The new solar cells work through free electron generation as a result of incident light striking them. The semiconductor layer prevents electron re-absorption, thereby being instrumental in achieving efficient power conversion. The charge is then extracted by the carbon ink.
The slot-die coating process ultimately delivers a printed output that consists of rollable, flexible solar cells printed on plastic film. This means that the possibility of printing large areas of solar cells is much closer. Yet there remains much that can still be achieved in this field, such as increasing the operational efficiency of the perovskite structures and finding ways of enhancing their longevity, either through using lamination or protective coating techniques.
Solar ink production in general is already proving to be an environmentally friendly option because it can be manufactured at relatively low temperatures, reducing energy consumption. In addition, the technique is valuable as demand for renewable solutions continues to grow, and that translates into greater opportunities for industry and economic growth as part of the broader green economy.
Publication inks encompass web offset (coldset and heatset) inks, sheetfed offset inks publication gravure inks and overprint varnishes. Packaging inks comprise flexographic inks, specialty gravure inks, radcure inks and overprint varnishes.
Sales of publication inks slumped by just over 15% in 2022 to 250,000 tons. Volumes of packaging inks sold were also down, this time by 4% at 530,000 tons. Scrying down into the details at national level, some salient points and indications emerge as follows:
• Of the big five economies in the west, Italy boasted the strongest annual growth in ink sales at 13.6%, increasing the value of inks to its economy to more than €400 million. Spain placed second with ink sales rising by 10.7% in 2022 to total more than €200 million. The UK and France increased sales by 8.5% and 6.9% respectively to both reach about €260 million. Germany remains the pre-eminent industry and market with sales in excess of €575 million and growing by 7.4%. After Germany, Italy boasts the most valuable ink sector.
• From the mid-sized and smaller economies, some of the best performers were the Netherlands, Czech Republic, Sweden, Croatia and Portugal, although none of these have ink sales in excess of €100 million and most have sales fewer than €50 million.
• In Eastern Europe disruption for some brought opportunity for others. Ukrainian ink sales fell by nearly 44% to around €13-14 million while those in neighbouring Belarus rose by 115% to about €12 million. Russian ink sales were seen to fare badly last year, collapsing by 35% to around €110 million. Meanwhile in the regionally prominent Turkish economy, turnover from inks grew by more than 24% to over €275 million. This means that the Turkish ink sector is now the third most valuable one in Europe after Germany and Italy.
Solar ink is not quite new but recent developments have been instrumental in advancing what can be achieved with printable solar cells. For the most part, this article looks at what the developments are in this area and what can be achieved.
Solar Ink
Solar ink is a form of conductive ink that potentially offers great versatility in being able to print solar cells onto a wide range of different substrates such as plastic, fabric and paper. The greater flexibility of solar ink printing lends itself to obvious consumer and construction advantages, the latter potentially including broad-wall applications for domestic solar power generation.The technology works around the production of thin yet flexible solar panels, and that in itself overcomes the limitations of fixed solar cell panels, which despite being seen as eco-friendly are energy-intensive to produce and fragile to handle.
Industry is also in a position where the requirements for producing traditional solar cells on the scale of 21st-century demand means that the materials needed for their manufacture will be depleted by the mid-century.
Recent advances in Europe have witnessed the emergence of solar cells that are both printable and rollable. Their production in laboratories has been developed under special conditions where water and oxygen are removed, furnishing cells that have an operational efficiency that matches the conventional solar cell.
Manufacturing these analogously in industry would be potentially very costly but aiming to print the cells on plastic film thwarts that particular challenge. Researchers at the University of Swansea have hence pioneered a technique for the on-film printing of perovskite solar cells using a carbon ink in conjunction with the slot-die coating process (a technique used for the production of photographic films).
One of the requirements for this been the development of perovskite and semiconductor layers that have thicknesses of 50 – 500 nm within the cell. Years of research have also delivered a process that eliminates the use of highly toxic solvents for solar cell production.
The new solar cells work through free electron generation as a result of incident light striking them. The semiconductor layer prevents electron re-absorption, thereby being instrumental in achieving efficient power conversion. The charge is then extracted by the carbon ink.
The slot-die coating process ultimately delivers a printed output that consists of rollable, flexible solar cells printed on plastic film. This means that the possibility of printing large areas of solar cells is much closer. Yet there remains much that can still be achieved in this field, such as increasing the operational efficiency of the perovskite structures and finding ways of enhancing their longevity, either through using lamination or protective coating techniques.
Solar ink production in general is already proving to be an environmentally friendly option because it can be manufactured at relatively low temperatures, reducing energy consumption. In addition, the technique is valuable as demand for renewable solutions continues to grow, and that translates into greater opportunities for industry and economic growth as part of the broader green economy.
Latest Statistics on European Sales
Meanwhile, turning back the clock slightly, the European Printing Ink Association (EuPIA) recently published its annual statistics for 2022 on the continent's printing ink sector. Overall trends indicate that volumes continue to fall while the value of printing inks sold continues to rise. The statistics are based on 26 member companies and they comprise 90% of the total sales.Publication inks encompass web offset (coldset and heatset) inks, sheetfed offset inks publication gravure inks and overprint varnishes. Packaging inks comprise flexographic inks, specialty gravure inks, radcure inks and overprint varnishes.
Sales of publication inks slumped by just over 15% in 2022 to 250,000 tons. Volumes of packaging inks sold were also down, this time by 4% at 530,000 tons. Scrying down into the details at national level, some salient points and indications emerge as follows:
• Of the big five economies in the west, Italy boasted the strongest annual growth in ink sales at 13.6%, increasing the value of inks to its economy to more than €400 million. Spain placed second with ink sales rising by 10.7% in 2022 to total more than €200 million. The UK and France increased sales by 8.5% and 6.9% respectively to both reach about €260 million. Germany remains the pre-eminent industry and market with sales in excess of €575 million and growing by 7.4%. After Germany, Italy boasts the most valuable ink sector.
• From the mid-sized and smaller economies, some of the best performers were the Netherlands, Czech Republic, Sweden, Croatia and Portugal, although none of these have ink sales in excess of €100 million and most have sales fewer than €50 million.
• In Eastern Europe disruption for some brought opportunity for others. Ukrainian ink sales fell by nearly 44% to around €13-14 million while those in neighbouring Belarus rose by 115% to about €12 million. Russian ink sales were seen to fare badly last year, collapsing by 35% to around €110 million. Meanwhile in the regionally prominent Turkish economy, turnover from inks grew by more than 24% to over €275 million. This means that the Turkish ink sector is now the third most valuable one in Europe after Germany and Italy.
