Agora Import Export:
https://www.agora-energiewende.de/service/agorameter/chart/power_import_export/10.02.2023/13.02.2023/today/https://www.stromdaten.info/ANALYSE/production/index.php

Fraunhofer Institut:
https://www.energy-charts.info/charts/power/chart.htm?l=en&c=DE&legendItems=111111111111111111111111000

Agora Marktdaten:
https://www.smard.de/page/home/marktdaten/78?marketDataAttributes=%7B%22resolution%22:%22hour%22,%22from%22:1674687600000,%22to%22:1675637999999,%22moduleIds%22:%5B1004066,1001226,1001225,1004067,1004068,1001228,1001224,1001223,1004069,1004071,1004070,1001227,5000410,6000411,2005097%5D,%22selectedCategory%22:null,%22activeChart%22:true,%22style%22:%22color%22,%22categoriesModuleOrder%22:%7B%7D,%22region%22:%22DE%22%7D

Smart Marktdaten:
https://www.smard.de/page/home/marktdaten/78?marketDataAttributes=%7B%22resolution%22:%22hour%22,%22from%22:1675119600000,%22to%22:1676069999999,%22moduleIds%22:%5B1004066,1001226,1001225,1004067,1004068,1001228,1001224,1001223,1004069,1004071,1004070,1001227,5000410,6000411,2005097%5D,%22selectedCategory%22:null,%22activeChart%22:true,%22style%22:%22color%22,%22categoriesModuleOrder%22:%7B%7D,%22region%22:%22DE%22%7D

Stromdaten.info:
https://www.stromdaten.info/ANALYSE/imexovertime/index.php

...energy & economy, Dr. Lars Schernikau: "The Future of Energy"
https://www.youtube.com/watch?v=NiHrCjqP4KQ

University of Sheffield, Gridwatch
https://www.gridwatch.templar.co.uk/index.php