Solar Power is a key component of the push for a zero carbon energy sector, and to meet this demand scientists are pushing the boundaries of what new materials and technologies will make up the next generation of solar panels.
The vast majority of solar panels currently manufactured today are made from silicon, which can reach efficiency levels of up to 24%. Efficiency is an extremely important factor of solar panels, as it measures just how much of the sun’s energy is being converted into electricity.
While solar panels have improved by leaps and bounds in recent years as investment has poured into the industry, there are hard limits with regards to what can be achieved with silicon.
The best solar panels on the market right now are approaching those limits, and new gains become harder to achieve as they get closer.
That is why research and development is now looking at Perovskite as the basis of the next generation of solar panel technology, especially when paired with other materials.
Named for German mineralogist Lev Perovskite, these synthetic minerals have the potential to truly revolutionise solar technology. Expected to start coming onto the market in just a few years, some of the earliest solar panels made using perovskites as their basis are already exceeding the best silicon solar panels’ efficiency.
James Dorrian, Managing Director of EnergyEfficiency.ie, said, “It’s great to see such promising trends in the the solar industry. Both from the ever growing interest people have in getting solar panels installed, and from new developments in solar technology.”
“Constantly pushing the envelope with solar technology is essential for encouraging new investment, and to assure people that solar power is an essential part of the future of the energy sector.”
“Improved efficiency levels will make solar panels a better long term investment, especially for solar PV systems where space is at a premium, such as domestic rooftop solar.”
Perovskite Tandem Cell Solar Panels
There are two main types of perovskite solar cells, single junction cells made purely of perovskites, and tandem cells where the perovskite works together with another semiconductor, usually silicon.
Tandem Solar Cells essentially work by stacking two or more solar cells on top of one another, each optimised to absorb a different part of the wavelength of light. This is where researchers and manufacturers are placing their money on the next generation of solar panels.
Perovskite-silicon tandem solar cells consist of a thin layer of perovskite on top of a silicon cell. The perovskite responds to the entire visible light spectrum, and even that near-infrared light which passes through it is absorbed by the silicon layer beneath and converted to electricity.
Tandem solar cells have achieved efficiencies significantly greater than what has been seen using any single material, and lab results have already surged past 30% efficiency.
LONGi Green Energy Technology currently holds the record for achieving 33.9% efficiency with a perovskite-silicon tandem solar cell in October 2023. While solar panels on the market never reach the same level of efficiency as cutting edge lab tests, this is still an incredible foundation to build on.
Indeed, the first full solar PV modules using Perovskite Tandem Solar Cells have already been manufactured just this year by a research team from the Fraunhofer Institute for Solar Energy Systems ISE using solar cells manufactured by Oxford PV.
This solar module has an efficiency of 25%, the world’s highest, a power rating of 421 watts, and covers an area of 1.68 square metres.
This means that the first perovskite-silicon tandem solar PV modules being manufactured have a greater efficiency than the top-performing silicon solar panels on the market today.
In addition, this panel was made using equipment already used in mass manufacturing today, which only needed modification for the new process. This means that the mass production of such solar panels might not be far off.
Perovskite substrates which are not bonded with silicon also have the advantage of being lightweight and flexible, making them suitable for a broader range of applications that rigid silicon solar cells.
Despite the promise of more efficient solar panels coming in the years ahead, James Dorrian added that waiting and holding off from investing in solar for that reason might not be the best decision.
“From a purely practical standpoint the sooner someone invests in solar PV, the sooner they will start to see savings on their electricity bills. Electricity prices are still above 2019 levels despite recent price cuts.”
“This makes now the best time for homeowners to have solar panels installed if they want to start cutting their dependence on electricity from the grid. Small gains in efficiency expected from new solar panels won’t compare with the time lost waiting for them to come to market.”
