Page 11 - North American Clean Energy September October 2015

can be used in rooftop systems or mounted on the ground. recycling is needed when the lifetime of the PV cell has
Perovskite solar cells can be integrated into glass and used
expired, although extra cost will be added as a result.

for building integrated photovoltaic (BIPV) applications

as well. heir use in smart glass may appear as one of the Lab-to-fab scaling needs investment

early applications of stand-alone perovskite solar cells, its Another diiculty in the scaling-up process is that while

transparency diferentiating it from c-Si roof panels.
perovskite solar cells show high eiciency in a lab with a

In addition, some companies are also targeting consumer device size of 10mm x 10mm, the modules used for real
electronics, wearables, and third-world application markets applications will need to be much larger. However, in larger

where the lexibility feature is a key added-value.
modules, the eiciencies drop. For instance, best performing

Most perovskite companies claim they will have irst devices generally have a low surface area of < 0.1 cm2.

module prototypes near 2017, and enter the market in 2018. Eiciency dropped by about 30% from 0.1 cm2 to 1 cm2 cell

However, there are some barriers in the perovskite systems.
area, mostly due to ill factor decrease. However, this can be
addressed with time.

Stability is the achilles heel

he biggest issue is the stability, or long term durability, of From no-man’s land to relevancy

perovskite PVs. For example, the most common perovskite he irony is that the two biggest issues – lifetime and toxicity

material used as the absorber is CHNHPbI. It degrades
– work against each other. Short lifetime applications (2-3
333in humid conditions and forms PbIat higher temperatures years), such as consumer and wearable electronics, would
2
due to the loss of CHNHI. he materials degrade in preferably use cheap, lexible PV; however, due to the
33
standard environmental conditions, leading to eiciency and toxicity, glass-based versions need to be used which limit the

performance drops.
form factor advantage. Even in glass, they would still need to

Studies shows perovskite solar cells can maintain more be recycled at the end of the product life, which is not very

than 80% of its initial eiciency after 500 hours, but after practical for high-volume, low-cost electronics. In contrast,
1,000 hours have minimal eiciency.
long-term ixed installations, such as BIPV, using toxic

herefore, applications in utility and BIPV will be materials can be acceptable provided they undergo managed

unfeasible if the stability issue cannot be solved. Some recycling, but here current perovskites struggle to work long

companies have claimed that glass-on-glass encapsulation enough for such applications. Successfully tackling these

will be used so it can solve most of the stability problem and issues could result in a large opportunity for perovskites.
extend the lifetime. But long lifetimes have not yet been Failing to do so may see the opposite.

demonstrated with glass encapsulation.
Perovskite solar technology is still young but has enormous

potential. New material systems, good barriers, better

Toxicity
stability, and non-toxic material research work are ongoing.

he next big concern is toxicity. CHNHPbIcan convert to And the bottom line is, those companies addressing some of
333 PbIwhen in contact with polar solvents such as water. PbI, the aforementioned issues will carve out a signiicant market
2 2
moderately water-soluble, is a carcinogen and is banned in share.

many countries. Lead-free perovskite solar cells can only

achieve an eiciency of about 6% today. hat means, unless Dr. Xiaoxi He is a technology analyst for IDTechEx Research.

new non-toxic material systems or good lexible barriers are Established in 1999, IDTechEx provides independent market
found, the current toxic perovskite system will be diicult research, business intelligence, and events on emerging

to use in consumer electronics applications, where they technology to clients in over 80 countries. IDTechEx is

would otherwise ofer a compelling beneit over other PV headquartered in Cambridge UK; additional oices are in Berlin,

technologies because perovskites could be cheaper and more Boston and Tokyo.

lexible. For this reason, many companies chose to sacriice

its potential lexibility, as encapsulation in glass can prevent IDTechEx Research | www.idtechex.com
the harm of toxicity. In addition, similar to CdTe systems,

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