For decades now, photovoltaic cells have provided clean electrical energy. The technology is inherently scalable, found in applications as small as garden lights and sprawling as solar energy farms. Mounted on rooftops, solar panels reduce a home’s dependence on fossil fuels. Constructed in vast fields, solar farms provide power for entire towns or facilities.

While more mature than the first generation of solar panels, current photovoltaic technology still only assures a sunlight-to-electricity conversion rate of approximately 22-47%, as illustrated in this factsheet created by the University of Michigan.

Despite the numerous types of photovoltaics on the market, including high-efficiency monocrystalline silicon panels and affordable thin film panels, increasing total panel surface area is still the only way to grow a meaningful electricity output from solar panels with efficiencies below 50%.

Yet, perovskites are a promising material that could disrupt the solar energy industry. Not only are the potentially one of the most efficiency PV technologies, they could also significant simplify panel assembly and construction.

The state of perovskite PV

Perovskites are emerging as a timely solution, addressing the market's growing demand for higher-efficiency solar cells. Their potential lies in specially formulated chemicals that can be incorporated into practical applications, creating lighter, affordable photovoltaics with intriguing new application characteristics.

The mined calcium titanium oxide substance was first discovered in the Ural Mountains in the mid-1800s, then gained the Perovskite label from mineralogist Lev Perovski. They are not a new technology, as scientists in 2015 were making quick strides to bring this into reality.

Most notably, best in class perovskite efficiencies outperform those of a similar gallium, silicon and thin-film technologies. They are only second to multijunction PV solutions in total efficiency.

Although there is currently added manufacturing complexity, and perovskite PV remains on the drawing board, if matured, manufacturing a perovskite PV panel will be a greener process than a silicon PV panel. Silicon-based cells require over 1,000° F of heat for production processes, which is a significant energy demand. The solution, at least in China, has been to place plants near coal mines.

Perovskite photovoltaics use significantly less energy in their production process, making them a more environmentally friendly option. They are also more likely to lend themselves to roll-to-roll manufacturing, which could greatly simplify and expedite the manufacturing process. That would also make them more adaptable for installations with unusual geometries or architecture.

What’s the catch?

Less waste, cheaper manufacturing, and higher photovoltaic energy conversion ratings, is it all too good to be true? Sort of.

Perovskites, in their raw form, don’t naturally inherit a uniform crystalline architecture. This minimizes recombination losses between layers with different energy-absorbing properties, thus leading to higher overall efficiency.

The above manufacturing problem and a few others have hindered perovskite PV fabrication, but these hurdles are not insurmountable. For example, the use of exotic films and improved manufacturing techniques are both being explored as avenues towards bringing Perovskite-based hybrids to market as low-cost, fast production solutions with efficiency ratings of 20% or more. They include film additives for planar efficiency improvements and a vacuum deposition process designed to eliminate film inconsistencies.

For the moment, lead is a key ingredient in these film supplements. This is a counterintuitive solution, as lead has very high biotoxicity, but its usage is potentially helping springboard a greener future. Scientists are actively researching alternative avenues that can provide the same benefits without the lead risks.

Also, unlocking the potential of perovskite cells, isn’t quite as straightforward as hoped. For one thing, cell encapsulation is a problem. Exposed to humidity and UV radiation, the cells degrade.

The latter issue is hard to defend; perovskite panels are, by definition, exposed to sunlight and need to exhibit ultraviolet resistance.

Perovskite PV in the real world

A solar panel that degrades from UV and environmental elements is a non-starter. It is why, although there have been leaps in perovskite PV efficiency and manufacturing, perovskites remains a drawing board solution.

Thankfully, research continues. Such as at Princeton University, where engineers made inroads into it perovskite panel longevity by introducing a capping layer. Only several atoms thick, the carbon disulfide layer increases panel lifespan to up to 30 years. Other research also look to active layers or additives to improve the material’s resilience without negatively affecting its efficiency. It remains an area of refinement.

However, the allure of perovskite PV remains too good to ignore. It is why multiple universities and organizations have sunk a decade or more of research into the technology. It would be an ideal candidate material, for say, an EV that gathers meaningful charge from its surface area. It is a technology that at least Toyota and Hyundai have considered.

So, is perovskite PV still the future of solar? It seems likely to have place among the solutions, at the very least. Applications will get more energy efficient. The need to efficient solar is growing. And the advantages it offers, seem like they will be urgently needed.