Swift Solar (United States)

Metal halide perovskites are a leading contender to disrupt not only terrestrial photovoltaic (PV) markets, but also the proliferating space PV markets. This is due to their impressive power conversion efficiencies, potentially low cost, and adaptability to flexible architectures. Here we assess the stability of three perovskite systems; a mixed Pb-Sn perovskite, and two mixed cation-triple halide systems. In all cases high tolerance to proton irradiation was observed. However, in the case of the mixed Pb-Sn system, irreversible decomposition of the perovskite along with the increased prevalence of defects was observed with thermal cycling. In the case of the mixed cation triple halides remarkable stability was demonstrated, in addition to self-healing, the results of which will be described here.

Mixed organic–inorganic halide perovskite solar cells (PSCs) are of interest for space photovoltaic applications due to their apparent tolerance to high-energy proton radiation. Here, the use of a more stable wide-bandgap FA0.8Cs0.2PbI2.4Br0.6Cl0.02 perovskite with thin encapsulation enables, for the first time, the detailed dependence of fluence and energy of energetic protons on device performance. Energies were chosen to provide the highest concentration of displacements within the active region, and therefore the highest amount of degradation. Not only are these devices tolerant when compared to conventional technologies, but an unexpected increase in open circuit voltage and power density is observed for increased electronic ionization when the proton energy is increased. This study aims to expand the description of the proton radiation tolerance to include not only nonionizing nuclear energy losses that are most detrimental to current technologies, but electronic ionization, which is shown to yield benefits in PSCs.

Opportunities for emerging PV technologiesTo achieve the lowest possible levelized cost of electricity (LCOE) in a given location, a PV system should have a low upfront cost ($ W -1 ), long lifetime (years), high energy yield (kWh kW -1 per year), and low cost of capital (%) (Jones-Albertus et al 2016).These economic metrics directly drive the technology metrics and primary goals for PV research and development.The upfront system cost is composed of module and non-module (balance-ofsystem, or BOS) costs.Many BOS cost components-including the cost of inverters, grid interconnection, inspection, permitting, taxes, and business overhead, among others-cannot be directly mitigated by improving PV technology.However, PV researchers can still help reduce both module and selected non-module costs.To reduce module costs, one can use low-cost materials, reduce raw materials usage (g W -1 ), and reduce module manufacturing time, labor, equipment, and energy requirements ($ m -2 or $ W -1 ).To reduce non-module costs, one can increase the module solar-to-electric power conversion efficiency (% or W m -2 ) and simplify transportation and installation.The system lifetime depends on the rate at which system performance degrades and informs projections of the system's practical operating lifetime.To extend the module and system lifetime-specified as T80, the time to reach 80% of the initial power output-PV technology research aims to reduce cell and module degradation rates (%/year).Performance stability must be evaluated under different environmental and operating conditions, such as elevated humidity and temperature, temperature and voltage cycling, and varying illumination levels.The energy yield represents the real-world system performance, and is directly related to system performance metrics such as capacity factor and performance ratio (Jean et al 2015).To maximize energy yield, one can use solar tracking or develop strategies to improve cell and module power output under low light, off-angle illumination, spectral variations, high temperature, and other non-ideal conditions -ideally without increasing module costs substantially.

This chapter introduces perovskite and quantum dot (QD) materials and their photovoltaic (PV) -related characteristics. The similarities and shared R&D challenges for perovskites and QD solar cells are described. The chapter gives a researcher’s perspective on these emerging technologies—what makes them scientifically interesting and technologically exciting.

Colloidal perovskite quantum dots offer potential stability advantages for solar cells over bulk perovskites but lag far behind in device efficiency. Now, a modified cation exchange method has been shown to improve the optoelectronic quality of perovskite nanocrystals, improving further the efficiency and stability of quantum dot solar cells.

The substantial capital expense of PV manufacturing has made it difficult for new technologies and companies to enter the market and compete on price with incumbents manufacturing modules at massive scale. We present a technoeconomic model that evaluates the start-up phase of a new PV manufacturing company by looking at the following question -how do you get a new solar cell technology to flourish under the current challenging market conditions? A cost-model for a small-scale roll-to-roll perovskite photovoltaic manufacturing line capable of producing 3.6 MW/year is developed and used to establish the expected low and high bounds on the production cost for flexible modules of $86/m <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> and $231/m <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> , respectively. We use these numbers to calculate economically sustainable annual growth rates for the company obtaining a wide range of possible values, depending on selling price and cost of manufacturing. We show that to sustainably grow a U.S.-based perovskite manufacturing company from 3.6 MW/year to over 100 MW/year in under 10 years requires selling products at an operating margin over 100%, a level that might be achievable in certain niche markets like the Internet of Things. The conclusion of this study extends to other materials systems with similar low-capex cost structures.