Solar energy has come a long way in recent decades. From bulky rooftop solar panels to sleek solar shingles, photovoltaic technology continues to evolve in design and efficiency.
The latest innovation in the industry is printable solar panels, offering a game-changing approach to generating renewable energy. As this technology matures, printable solar promises to transform how we harvest the sun’s immense power.
What are printable solar panels?
Printable solar panels are thin, flexible sheets of solar cells that can be printed directly onto surfaces like plastic, glass, fabrics, and metal. This allows the cells to conform to the shape of the surface, opening up many new possibilities for solar integration.
The printing is accomplished using modified inkjet or screen printers with conductive inks made of silver nanoparticles or other photovoltaic materials.
A thin layer of these special inks is printed in a specific pattern onto the substrate, forming the current-collecting grid and photon-absorbing layer of the solar cell.
What are printable solar panels made of?
There are a few materials that make up the anatomy of a printable solar cell:
- Substrate – This forms the base layer on which the solar cell is printed. It can be plastic, glass, aluminium, fabrics, or other flexible surfaces.
- Conductive ink – Silver nanoparticle ink is most commonly used to print the conductive electrodes and interconnects of the solar cell. Other conductive inks are also being developed using materials like graphene.
- Photovoltaic inks – These specialised inks contain light-sensitive chemicals like perovskites or organic PV compounds, which absorb photons and generate electric current when printed onto the electrodes.
- Encapsulating film – A thin, transparent film that protects the printed solar cell from weather, dust, and mechanical damage.
How much energy do printable solar panels produce?
The power conversion efficiency of printable solar cells has increased steadily in recent years.
Lab test results have achieved efficiencies of over 15%, with commercially available panels ranging from 5-8%. This is less than conventional silicon panels, which operate around 15-22% efficiency.
However, printable solar makes up for this with substantial cost savings during production, flexibility, and adaptability. The efficiency gap is expected to narrow significantly with ongoing research and development. Current projections estimate printable solar will hit 15-20% efficiency – on par with silicon – within 5-10 years.
How are printable solar panels made?
Manufacturing printable solar panels involves specialised equipment and multiple stages of printing:
- Design – The solar cell circuitry is laid out and optimised using CAD software. This allows customisation of the panel shape and circuit printing pattern.
- Cleaning & surface prep – The substrate surface is thoroughly cleaned and prepared for optimal ink adhesion.
- Print conductive electrodes – Silver nanoparticle ink is printed onto the substrate in thin wires, forming the front and back electrodes of the cell. High precision is needed to avoid short circuits and maximise conductivity.
- Print photovoltaic layer – The light-sensitive PV ink is printed onto the electrodes, aligning with the terminal contacts. Multiple overlapping print layers are often used to tune the material properties.
- Encapsulation – A protective plastic film is applied using heat or adhesive laminating, sealing the panel from moisture, oxygen, and abrasion.
- Electrical testing & analysis – The completed panels undergo testing to ensure power output meets specifications before shipment.
Benefits of printable solar panels
Compared to conventional solar panels, printable PV offers some unique advantages:
Affordability
Printable solar panels can be produced at a fraction of the cost of traditional panels. With inkjet printing, solar cell materials are deposited only where needed, reducing material waste.
Reel-to-reel high-volume printing is a way to make solar panels much cheaper and faster than before. It works by printing the solar cells on a continuous roll of material, which is much more efficient than traditional manufacturing methods. This could make solar power more affordable and accessible to everyone.
Flexibility
The thin, pliable nature of printed solar cells gives them unmatched versatility. They can stick to curved surfaces, bend around edges, and easily integrate onto products, buildings, vehicles, textiles, etc. This flexibility opens up many new applications that are impossible with rigid panels.
Sustainability
Manufacturing printable solar panels has less environmental impact than silicon panel production. Low-temperature printing reduces energy consumption, and the panels are printable on recyclable plastics and biopolymers.
Being lightweight, they also require less transportation emissions. Printable solar panels are, therefore, an eco-friendly renewable energy solution.
Applications of printable solar cells
This versatile technology is making solar integration possible in many new contexts:
In homes
Printable solar cells can adhere to curved surfaces like window frames, skylights, and glass facades. They can also cover flat roofs. Panels can be custom cut and printed to seamlessly meld onto architectural features, bringing solar generation directly to living spaces.
Commercial use
Businesses can leverage printable PV in creative ways, sticking panels onto windows, walls, billboards, and outdoor equipment. Larger installations on warehouses, factories, and commercial rooftops are also applicable.
However, they may not yet be commercially viable regarding energy output. While they are convenient to stick and use on commercial buildings, they may need to provide more energy to meet the demands of businesses that require a lot of power.
Remote areas
The lightweight nature of printable solar makes it ideal for remote and mobile applications. Panels can power satellites, space vehicles, and unmanned aerial vehicles. They can provide off-grid power for sensors, farming equipment, camping gear, and emergencies.
In addition, printable solar panels can be used to power sensors in remote rural areas to monitor environmental conditions or agricultural yields. They can also power offshore oil rigs and shipping vessels, which often have limited access to grid-based electricity.
Challenges and solutions
While promising, printable solar technology still has areas for improvement:
Technical challenges
Efficiency, though improving, still needs to catch up to silicon photovoltaics. Durability and weather resistance also need enhancement to match the 25+ year lifespan of conventional panels. Ongoing R&D into the conductive, photovoltaic, and encapsulating inks can overcome these challenges.
Environmental concerns
Some printed solar cell compounds use lead and other toxic materials. Work is underway to optimise non-toxic organic PV inks and develop eco-friendly processing methods. The introduction of stringent industry regulations will also help address environmental impacts.
The future of printable solar panels
The market potential for this burgeoning technology is vast. The printed solar panel market is projected to grow over 25% annually over the next decade. With expanded manufacturing capabilities, costs are forecast to continue falling, making adoption more widespread.
Advances in organic PV and perovskite ink efficiency and breakthroughs in graphene and carbon nanotube conductors could push printable solar well beyond 20% efficiency in the near future. This would drive a surge in large-scale adoption across industries.
Combining printable solar with other technologies like batteries, smart fabrics, electric vehicles, and the Internet of Things can pave the way for a solar-powered tomorrow. Printable photovoltaics are poised to transform energy access and sustainability worldwide from smart cities to off-grid villages.
Conclusion
Printable solar panels usher in an exciting new phase in renewable energy. As the technology matures, it promises to make solar generation ubiquitous and accessible to all.
With its versatility, customisability, and affordability, printable solar can unlock myriad possibilities for a clean energy future. From powering homes to fueling the growth of smart connected devices, this game-changing innovation begins a solar revolution.
