On the outskirts of Brandenburg an der Havel, Germany, lies a factory that promises to revolutionize the future of solar energy. There, British company Oxford PV produces solar cells that use perovskites, a material that many consider key to the future of solar energy. These cells represent a new type of perovskite-based technology that could change the landscape of renewable energy.
Solar technology factory
The Oxford PV factory is surrounded by tranquil countryside, but inside it innovations are being developed that could transform solar energy production. Chris Case, the company’s chief technology officer, describes the site as “the realisation of my deepest aspirations”.
Oxford PV, along with other companies such as QCells, has put its faith in perovskite technology. This relatively cheap and easily available photovoltaic material has shown great potential in improving the efficiency of solar panels. In fact, commercial solar panels with perovskite-silicon cells are expected to enter the market next year.
As for other companies in this field, Hanwha QCells announced its intention to invest 100 million dollars in a production line for tandem solar cells, integrating silicon and perovskite, a technology that will be operational by the end of 2024. This shows that major brands are betting heavily on this innovation.
A new type of solar cell with perovskite technology
The fascinating thing about solar cells made with perovskite is their ability to capture a greater amount of sunlight compared to conventional silicon cells. By integrating both materials, through what is known as tandem solar cells, the overall energy conversion efficiency can be increased. While silicon solar cells alone can achieve up to 26% efficiency, tandem cells with perovskite easily exceed this limit, achieving up to 31,6%, as recently demonstrated by the Fraunhofer Institute.
Tandem cells have the advantage of capturing a wider range of solar wavelengths. This allows for up to 20% higher energy output compared to traditional silicon cells. However, the initial cost of perovskites remains a challenge, although proponents of the technology point out that in dense urban areas or industrial complexes where land is limited, the increased electricity generation will quickly offset the additional expense.
Impact of the new type of perovskite solar cell
The impact of this technology is significant. Unlike silicon cells, perovskite cells can be manufactured at much lower temperatures, which reduces production costs. They are also more flexible and lighter, and can be applied to a wider variety of surfaces, such as balconies or even window frames.
The solar energy market is expected to need up to 75 terawatts (TW) capacity installed by 2050 compared to 1,2 TW today. Despite advances in perovskites, the challenge remains their durability. Even so, important advances in materials and surface treatments, such as the passivation, are significantly improving their long-term stability.
For example, researchers have found that passivation using aminosilanes can improve both the efficiency and operational stability of perovskite cells. Thanks to these treatments, up to 95% of the original efficiency has been preserved after 1.500 hours of use under extreme conditions.
Records in efficiency
Perovskite solar cells have evolved very quickly. While in 2009 they could only convert 3,8% of sunlight into energy, current versions already achieve 26,1% efficiency, and even 31,6% in tandem form with silicon, as mentioned above.
In addition, some laboratories around the world are exploring even more advanced versions of these cells, such as cells perovskite-perovskite tandem, which do not use silicon at all, and have already reached an efficiency of 28,49%. Although these versions are still in development, they offer the possibility of even greater energy generation thanks to their ability to capture different parts of the solar spectrum with materials that are much cheaper than silicon.
In practical terms, these advances not only overcome the traditional limits of solar cells, but could reduce the overall cost of these technologies, making them more accessible and flexible for a wide range of applications. This is key to the mass adoption of solar energy around the world.
With all these innovations, although there are still challenges to be solved, such as degradation in the face of humidity or heat, perovskite is on its way to generating a true revolution in the renewable energy industry. If advances in durability can match those in efficiency, perovskites are likely to surpass current technologies and radically change the way the world consumes solar energy.
As we watch this technology continue to break record after record, there is no doubt that we are on the cusp of a new era for solar energy – one where clean energy will be more efficient, accessible and viable than ever before.