Extreme events in the European renewable power system:Validation of a modeling framework to estimate renewable electricity production and demand from meteorological data

With the need to reduce greenhouse gas emissions, the coming decades will see a transition of Europe's power system, currently mainly based on fossil fuels towards a higher share of renewable sources. Increasing effects of fluctuations in electricity production and demand as a result of meteorological variability might cause compound events with unforeseen impacts. We constructed and validated a modeling framework to examine such extreme impact events on the European power system. This framework includes six modules: i) a reservoir hydropower inflow and ii) dispatch module; iii) a run-of-river hydropower production module; iv) a wind energy production module; v) a photovoltaic solar energy production model; and vi) an electricity demand module. Based on ERA5 reanalysis input data and present-day capacity distributions, we computed electricity production and demand for a set of European countries in the period 2015–2021 and compared results to observed data. The model captures the variability and extremes of wind, photovoltaic and run-of-river production well, with correlations between modelled and observed data for most countries of more than 0.87, 0.68 and 0.65 respectively. The hydropower dispatch module also functions well, with correlations up to 0.82, but struggles to capture reservoir inflows and operating procedures of some countries. A case study into the meteorological drivers of extreme events in Sweden and Spain showed that the meteorological conditions during extreme events selected by the model and extracted from observational data are similar, giving confidence in the application of the modeling framework for (future changes in) extreme event analysis.</p

Local balancing of the electricity grid in a renewable municipality; analyzing the effectiveness and cost of decentralized load balancing looking at multiple combinations of technologies

With the integration of Intermitted Renewables Energy (I-RE) electricity production, capacity is shifting from central to decentral. So, the question is if it is also necessary to adjust the current load balancing system from a central to more decentral system. Therefore, an assessment is made on the overall effectiveness and costs of decentralized load balancing, using Flexible Renewable Energy (F-RE) in the shape of biogas, Demand Side Management (DSM), Power Curtailment (PC), and electricity Storage (ST) compared to increased grid capacity (GC). As a case, an average municipality in The Netherlands is supplied by 100% I-RE (wind and solar energy), which is dynamically modeled in the PowerPlan model using multiple scenarios including several combinations of balancing technologies. Results are expressed in yearly production mix, self-consumption, grid strain, Net Load Demand Signal, and added cost. Results indicate that in an optimized scenario, self-consumption of the municipality reaches a level of around 95%, the total hours per year production matches demand to over 90%, and overproduction can be curtailed without substantial losses lowering grid strain. In addition, the combination of balancing technologies also lowers the peak load to 60% of the current peak load in the municipality, thereby freeing up capacity for increased demand (e.g., electric heat pumps, electric cars) or additional I-RE production. The correct combination of F-RE and lowering I-RE production to 60%, ST, and PC are shown to be crucial. However, the direct use of DSM has proven ineffective without a larger flexible demand present in the municipality. In addition, the optimized scenario will require a substantial investment in installations and will increase the energy cost with 75% in the municipality (e.g., from 0.20€ to 0.35€ per kWh) compared to 50% (0.30€ per kWh) for GC. Within this context, solutions are also required on other levels of scale (e.g., on middle or high voltage side or meso and macro level) to ensure security of supply and/or to reduce overall costs

Fetal MRI of the heart and brain in congenital heart disease

Antenatal assessment of congenital heart disease and associated anomalies by ultrasound has improved perinatal care. Fetal cardiovascular MRI and fetal brain MRI are rapidly evolving for fetal diagnostic testing of congenital heart disease. We give an overview on the use of fetal cardiovascular MRI and fetal brain MRI in congenital heart disease, focusing on the current applications and diagnostic yield of structural and functional imaging during pregnancy. Fetal cardiovascular MRI in congenital heart disease is a promising supplementary imaging method to echocardiography for the diagnosis of antenatal congenital heart disease in weeks 30–40 of pregnancy. Concomitant fetal brain MRI is superior to brain ultrasound to show the complex relationship between fetal haemodynamics in congenital heart disease and brain development.</p