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Thin films of Cu 3 BiS 3 have been produced by conversion of stacked and co electroplated BiCu metal precursors in the presence of elemental sulfur vapour. The roles of sulfurization temperature and heating rate in achieving singlephase good quality layers have been explored. The potential loss of Bi during the treatments has been investigated, and no appreciable compositional difference was found between films sulfurized at 550 °C for up to 16 hours. The structural, morphological and photoelectrochemical properties of the layers were investigated in order to evaluate the potentials of the compound for application in thin film photovoltaics.

CuSbS 2 and Cu 3 BiS 3 are being investigated as part of a search for new absorber materials for photovoltaic devices. Thin films of these chalcogenides were produced by conversion of stacked and coelectroplated metal precursor layers in the presence of elemental sulfur vapour. Exsitu XRD and SEM/EDS analyses of the processed samples were employed to study the reaction sequence with the aim of achieving compact layer morphologies. A new "TimeTemperatureReaction" (TTR) diagram and modified PillingBedworth coefficients have been introduced for the description and interpretation of the reaction kinetics. For equal processing times, the minimum temperature required for CuSbS 2 to appear is substantially lower than for Cu 3 BiS 3 , suggesting that interdiffusion across the interfaces between the binary sulfides is a key step in the formation of the ternary compounds. The effects of the heating rate and sulfur partial pressure on the phase evolution as well as the potential losses of Sb and Bi during the processes have been investigated experimentally and the results related to the equilibrium pressure diagrams obtained via thermochemical computation.

A rapid screening methodology for the development of transparent conducting oxides is presented. The methodology, based on a combination of spectrophotometry, ellipsometry and 4-point probe measurements, was used to map out the opto-electronic properties over a co-sputtered ZnO : Al2O3 film deposited from separate ceramic targets of ZnO and Al2O3. Clear distributions for the carrier density, n e, and mobility, μ e, are determined as a function of wt%. Al2O3 content within the film. A minimum resistivity value of 7.6 × 10−4 Ω cm was achieved for a composition of 1.5 wt%. Al2O3.

Abstract. In this paper, a field test of wake steering control is presented. The field test is the result of a collaboration between the National Renewable Energy Laboratory (NREL) and Envision Energy, a smart energy management company and turbine manufacturer. In the campaign, an array of turbines within an operating commercial offshore wind farm in China have the normal yaw controller modified to implement wake steering according to a yaw control strategy. The strategy was designed using NREL wind farm models, including a computational fluid dynamics model, SOWFA, for understanding wake dynamics and an engineering model, FLORIS, for yaw control optimization. Results indicate that, within the certainty afforded by the data, the wake-steering controller was successful in increasing power capture, by amounts similar to those predicted from the models.