Tips Wanted: Cover engine with cool wind (split saving) ?!

Hello, Some vehicles, for example, use devices that allow the engine to be protected from wind in cold conditions (automatic locking system on the radiator grille) and thus reach its operating temperature faster. Certainly, I am not the only one who comes up with the idea that try on your own car and wanted to inquire about your experience. What experiences have you had with covering the cooler for the cold season? Fuel saving effect ? Mfg bluskoda