Solar technology is getting better and better, pushing the boundaries of what we can expect from renewable energy sources. With the next generation of solar panels on the near horizon, we could see the solar market completely change by the end of the decade.
One of the biggest technologies that the solar industry is paying close attention to is the development of solar panels using Perovskite. Perovskite is a type of crystalline material that can be made with many different potential chemical make-ups and has proven incredibly efficient in laboratory settings while also unlocking unique possibilities for solar photovoltaic generation. We will break down this incredible technology below.
Perovskite Photovoltaic Cells
Perovskite photovoltaic technology is something to keep an ear out for – a burgeoning technology that promises to be way more efficient than the silicon-based panels that dominate the market today.
Within laboratory conditions, photovoltaic cells made from a crystalline material called Perovskite have reached incredible degrees of efficiency – with solar-cell efficiencies recorded in labs reaching heights between 25% approaching 34%. While these advances are remarkable, we will explore the advancement, and what’s holding this tech back from being available today.
What is Perovskite?
Perovskite is a type of crystalline structure which in solar cell implementations is typically made of a hybrid organic-inorganic halide-materials, with methylammonium lead halides being one of the most common, however, other chemicals have been used to generate these materials.
Right now, these solar cells have already proven numerous benefits over the traditional silicon-based solar cell. The unique properties of the perovskite cell are perfectly suited for photovoltaic cells, as they boast high efficiency and wide absorption ranges. The efficiency of these Perovskite cells allows them to be made incredibly thin – between 300 and 900 nm thick – while maintaining effectiveness. This is many times thinner than what is possible with silicon-based cells.
Another selling point is a relative improvement in ease and cost of manufacturing. Compared to Silicon cells, whose manufacturing requires “expensive, multi-step processes, conducted at high temperatures (>1000 °C) under high vacuum in special cleanroom facilities”, standard Perovskite cells can be made in a more conventional laboratory setting without the high temperatures and less materials.
https://www.nature.com/articles/ncomms8497
The Roadblock
So, what’s the hold up? Why hasn’t this incredible material already dominated the solar industry already? Right now, the main aspects of the technology that are holding it back from commercial viability come down to “a lack of stability and durability”.
Exposure to either moisture or oxygen can cause a Perovskite cell to degrade, greatly diminishing its effectiveness. Other factors, including prolonged exposure to weather, UV light and thermal stress can also contribute to these durability issues. Compared to our current silicon-monocrystalline solar cell that easily lasts for 25-30 years, this is a huge problem to solve before the technology is ready for commercial application.
Additionally, “because of their sensitivity to environmental conditions, it’s also difficult to fabricate perovskite cells with consistent quality”, putting a potential damper on the otherwise inexpensive production of these cells.
Another downside is that many of the promising solar cells are made out of a lead compound, which combined with the lack of durability, leads to the potential of leaking lead, which has known negative health and environmental impacts.
Researchers are busy trying to find solutions to these problems, and there are definitely some promising innovations, but it seems we are still a few years away from perovskite solar panels reaching commercial production.
Potential Developments with Perovskite
Tandem Cells
One of the biggest benefits of perovskite, specifically methylammonium lead halide perovskite cells, is that the optical bandgap (the portion of solar spectrum a photovoltaic cell absorbs) can be manipulated by adjusting the content of halide.
This, combined with the fact that perovskite cells can effectively work when applied as a thin film enables synergy with other solar cells, which when tuned to absorb complimentary wavelengths of light, create highly efficient “tandem cells”.
By applying a thin perovskite film to silicon cells, researchers have been able to expand the efficiency of the tandem cell significantly. Silicon-Perovskite tandem cells have been able to reach the highest current level of generation, just underneath 30% efficiency. Researchers have also experimented with tandem panels with two different types of Perovskite, tuned to different absorption ranges, or attempting to layer three or more cells with different bandgaps on top of each other.
Quantum Dot Solar Cells
Perovskite has some other applications in the quest to develop the next generation of solar panels. Another way that researchers are experimenting is with quantum dot technology, similar to what might be in your new HD TV.
Quantum dots are “semiconducting nanocrystals with typical dimensions ranging from several to tens of nanometres, capable of controlling photoelectric properties based on their particle size”. In other words, each “quantum dot” is an extremely small particle that when illuminated, emits a colour of light, which is controllable through the size of the particle.
The basic principle of quantum dot solar cells is that the quantum dots can convert light to a certain wavelength of light, which the solar cell portion can be tuned to absorb to convert into electricity.
Earlier in the year, researchers from the Ulsan National Institute of Science & Technology in South Korea created a solar cell using Perovskite along with QD technology that had a solid efficiency of 18.1% – the highest efficiency of its kind recognized by the National Renewable Energy Laboratory (NREL).
Experiments with quantum dot solar cells utilizing Perovskite are promising but have had their share of issues that need to be overcome before mass production is possible. In particular, scalability and durability are big question marks that will need to be overcome before quantum dot solar cells reach commercial viability.
It is also unforeseen if QD solar cells will overtake tandem cells in terms of efficiency, or what role QD cells will play in the next generation of solar generation.
Transparent solar panels
We all know what solar panels look like today, but it is entirely possible we have no idea what they will look like in 10-15 years. As the technology further develops, one way we might be able to change the landscape of solar generation is by expanding how the technology will be applied.
One example in how we could expand how we use solar photovoltaic technology is solar windows. These windows are designed to generate electricity from the invisible wavelengths of light while letting the visible wavelengths through (so we can still appreciate the view outside).
There are a few different methods of creating solar windows. One example is Ubiquitous Energy, one of the leaders in developing solar windows, which has had success so far by integrating organic solar cells into windows. However, companies are looking into the possibility of Perovskites to fill this role, including tech giant Panasonic, who are in the R&D stage of their Perovskite solar windows.
Using less of the full spectrum of light than traditional solar panels in order to be transparent, these windows prove to be less efficient than traditional solar panels. However, Panasonic have stated that they are testing solar technology that has reached efficiency comparable to residential silicon solar panels. Whether the other roadblocks of Perovskite might be overcome to add solar generation to our windows will be determined over the next few years.
EnergyRates.ca
We specialize in helping you find the electricity and natural gas plans that work with your home or business energy priorities. Whether that’s meeting your sustainability goals or just cutting your energy costs we can help you find what works. Fill out the form above to get started.
