Recent  

In this paper we study how the momentum extracted by wind turbines get replenished so that the wind farm can continue to function. We use a numerical model to simulate the dynamics of a hypothetical coastal wind farm in the Arabian Sea under sea breeze conditions. Results show that vertical turbulent eddies can replenish more than half of the lost momentum, but horizontal advection also plays a role near the wind farm edges especially in sparsely packed wind farms.

The goal of the EMN is a harmonized, sustainable, coordinated and intelligently specialized infrastructure to support the needs expressed in the European Radiation Protection Ordinance. Such an EMN under the umbrella of EURAMET is in the founding phase and is being prepared in parallel by the EMPIR project 19NET03 supportBSS with five technical work packages. EURAMET is the Regional Metrology Organisation (RMO) of Europe. The EMN was established by signature on 16 September 2021.

Flow patterns in fractal-fracture networks where the apertures scale as a power-law and a set of dominant sub-networks generated from a given fractal-fracture map by systematically removing the smaller aperture fractures is investigated. The recovery curves and TOFs of each network and its dominant sub-networks at different time steps are compared. Results show that in the case of such scaled aperture fractal-fracture systems, smaller fractures do not significantly contribute to the fluid flow.

The geothermal reservoir at Waiwera has been subject to active exploitation for a long time. However, the continuous production of geothermal water, to supply hotels and spas, had a negative impact on the reservoir. The aim of this work was to link the influence of the abstraction rates to the measured water level data to derive reservoir properties. For the analysis, a modified deconvolution algorithm was implemented and shown to be applicable and in accordance to results of a pumping test.

Uranium migration in the Swiss Opalinus Clay is used as an example to quantify the influence of varying values of a stability constant in the underlying thermodynamic database within the law of mass action on the migration lengths. The difference of the stability constant of 1.33 log units lead to changed migration lengths of 5 m to 7 m. With a maximum diffusion distance of 22 m the influence of an uncertain stability constant is negligible for the host rock scale.

In this study we evaluated subseasonal-seasonal scale forecasts of solar radiation, wind speed, temperature and relative humidity over India from 6 global models by comparing against observations. Results show that the overall quality of the forecasts are not good. However, they demonstrate enough skill suggesting that further improvement through calibration may make then useful for the renewable energy sector.

Events like mid-latitude storms with their high winds have an impact on wind energy production and forecasting of such events is crucial. This study investigates the capabilities of a global weather prediction model MPAS and looks at how key parameters like storm intensity, arrival time and duration are represented compared to measurements and traditional methods. It is found that storm intensity is represented well while model drifts negatively influence estimation of arrival time and duration.

The German site selection procedure to identify a site for the disposal of high-level radioactive waste is ongoing. The current step of the procedure includes representative preliminary safety analyses, for which the methodology is described and a first insight on the implementation is given. We aim to provide a document to boost communication and discussion with the scientific community and the public, although the implementation is at an early stage and may be subject to numerous changes.

Barite formation is an important factor for many use cases of the geological subsurface because it may change the rock. In this modelling study, the replacement reaction of celestite to barite is investigated. The steps that were identified to play a role are celestite dissolution followed by two-step precipitation of barite: spontaneous formation of small crystals and their subsequent growth. Explicitly including the processes improve the usability of the models for quantified prediction.

Space heating makes up around 67 % of the average energy consumption in german households. While this number decreases with increasing energy standards for buildings, many heating systems still run on fossil fuels. Here, we present a method to realistically estimate the heating demand of a building, This estimated heat demand is connected to a modelled geothermal energy source, for calculating, if geothermal energy can supply the needed heat, and if more such installations influence each other.

RedModRphree is an R extension package to leverage the PHREEQC engine for geochemical models, providing convenience functions to efficiently setup computations and program algorithms involving geochemical models. Version 0.3.6 ships with a novel implementation of Pourbaix (potential/pH) diagram computation which considers the full speciation of the solution at each diagram point.

Depletion of conventional hydrocarbon deposits requires implementation of the enhanced oil recovery methods, particularly based on carbon dioxide injection. The article aims at an accelerated optimisation of such methods performance by means of numerical modelling. We propose an optimisation algorithm based on the construction of a hierarchy of compositional reservoir models. We give examples of the algorithm application and discuss its performance.

We model two kinds of demand for public charging infrastructure: As compensation for the lack of home charging points, and based on points of interest. We combine those two demands with the available parking spaces and generate distributions for possible future charging points. We use a raster-based approach on a municipality’s full grid. The model is compared with three other models in a correlation comparison in order to determine the influence of certain model assumptions and input data.