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This paper investigates China's capability to exert power on Rare Earth markets until 2020. A dynamic partial equilibrium model allowing for a disaggregated representation of the mining sector and endogenous investment in capacities is developed. The model is calibrated on a novel dataset on Rare Earth mines. Simulations show that Chinese market power is a transitory phenomenon. In 2014 and 2015, Light Rare Earth prices increase by 21 per cent and Heavy Rare Earth prices more than double compared to free trade, if assuming export restrictions to remain unchanged. Market power on Light Rare Earths vanishes almost completely by 2017 due to the entry of new suppliers, while it persists until 2019 for Heavy Rare Earths. Export restrictions imply a loss of Marshallian welfare of US$ 1.96 billion outside China. In the short run, even moderate cuts in export quotas can increase exerted market power substantially. Altering tariffs induces smaller but more persistent effects. Sensitivity checks indicate that the results are robust, but delayed opening of new mines and demand shocks can be important for China's capability to exert market power.

International audience; Because of the cloud-induced variability of the solar resource, the growing contributions of photovoltaic plants to the overall power generation challenges the stability of electricity grids. To avoid blackouts, administrations started to define maximum negative ramp rates. Storages can be used to reduce the occurring ramps. Their required capacity, durability, and costs can be optimized by nowcasting systems. Nowcasting systems use the input of upward-facing cameras to predict future irradiances. Previously, many nowcasting systems were developed and validated. However, these validations did not consider aggregation effects, which are present in industrial-sized power plants. In this paper, we present the validation of nowcasted global horizontal irradiance (GHI) and direct normal irradiance maps derived from an example system consisting of 4 all-sky cameras (“WobaS-4cam”). The WobaS-4cam system is operational at 2 solar energy research centers and at a commercial 50-MW solar power plant. Besides its validation on 30 days, the working principle is briefly explained. The forecasting deviations are investigated with a focus on temporal and spatial aggregation effects. The validation found that spatial and temporal aggregations significantly improve forecast accuracies: Spatial aggregation reduces the relative root mean square error (GHI) from 30.9% (considering field sizes of 25 m2) to 23.5% (considering a field size of 4 km2) on a day with variable conditions for 1 minute averages and a lead time of 15 minutes. Over 30 days of validation, a relative root mean square error (GHI) of 20.4% for the next 15 minutes is observed at pixel basis (25 m2). Although the deviations of nowcasting systems strongly depend on the validation period and the specific weather conditions, the WobaS-4cam system is considered to be at least state of the art.

Bio Suisse erlaubt ab 2022 für Wiederkäuer nur noch 100 Prozent Schweizer Biofutter. Dies erhöht die Nachfrage nach Körnerleguminosen – so auch nach Lupinen. Die Schmal blättrige (Blaue) Lupine ist gesund, braucht aber kalkfreie Böden (pH unter 6,5). Hoffnung wecken zwei neue Sorten der Weissen Lupine.