Environmental assessment of electrically controlled variable light transmittance devices

Abstract

A comprehensive benchmark analysis has been performed on five electrically controlled state-of-theart transmittance modulation devices including their production routes, from 'cradle-to-gate'. The benchmarks have been modeled employing the GaBi life cycle assessment software tool, which successfully yielded the most important environmental problem areas for the product life cycles of electrochromic and electrotropic light-modulating devices. In terms of the energy demand of processing, all-solid-state technology was found to be less favorable than wet-chemical electrodeposition processes; however, the effect is interestingly overcompensated for by the resource depletion resulting from higher layer thicknesses in the latter case. As opposed to the mineral-glass based benchmarks, a plastic-film based system was particularly favorable, implying that the substrate is a factor with a strong environmental impact in transmittance modulation devices. Eventually, very high impacts were found for tin-doped indium oxide (ITO) and iridium oxide, i.e. a common transparent conductor and anodic electrochromic material, respectively. The results obtained support important current trends such as in-line manufacturing of electrochromic devices, the quest for ITO replacement materials, and, in general, the replacement of energy- and resource-intensive processes (sputter deposition of heavy metal oxides) by less demanding methods

Perovskite photovoltaics: life-cycle assessment of energy and environmental impacts

“…10 The masses of the cleaning solvents, adhesives, and polyethylene terephthalate (PET) are extracted from the literature. 23,34,41 The masses of blocking layer (BL)-TiO 2 ink, nanocrystalline (nc)-TiO 2 ink, PbI 2 , CH 3 NH 3 I, spiro-OMeTAD, and gold are derived based on the thickness of the corresponding layers, the active area ratio of the module, and the material utilization efficiency; the masses of dimethylformamide, isopropanol, and chlorobenzene are calculated according to the concentrations of corresponding solutions. Since the material utilization efficiencies are not reported for perovskite PV modules, we assume that the material utilization efficiencies for spin-coating, spray pyrolysis, and thermal evaporation are 30.0%, 32 80.0%, 42 and 82.0%, 43 respectively.…”

Hierarchical structure Ti-doped WO3 film with improved electrochromism in visible-infrared region

“…where A is the interface between the electrolyte and the active material, C is the concentration of species in the bulk (mol cm 23 ), n is the number of electrons involved in the redox process (n = 1 for W 5+ /W 6+ redox pair), and v is the potential scan rate (V s 21 ). As shown in the insets of Fig.…”

“…[5][6][7][8][9][10][11][12][13][14][15][16][17][18] Until recently, most of the applications have been based on the optical changes in the visible spectrum, whereas the infrared (IR) region is still rare. 4,[19][20][21][22][23][24][25][26] Electrochromic materials can be also used in the IR region, such as infrared camouflage and thermal control of satellites. 27,28 Tungsten trioxide (WO 3 ) has been identified as one of the most promising inorganic electrochromic materials due to its outstanding properties.…”

Electrochromism: from oxide thin films to devices

“…Among them, indium tin oxide (ITO) remains the state of the art [13]. Besides excellent optoelectronic properties, the as-made ITO transparent electrodes suffer from major limitations like costly fabrication process and brittleness as well as a high environmental impact as reported by Posset et al from Life Cycle Assessment study [14]. Indeed, the instability of ITO to mechanical constraints prevents its use for fabrication of flexible devices.…”