Convert to UTF8 and replace original file

The following script example can handle none empty files.

#!/bin/bash
for orig_file_name in $(ls ./SOURCE_DIR); do
   iconv -f UTF-16 -t UTF-8 ./SOURCE_DIR/${orig_file_name} -o ./TARGET_DIR/${orig_file_name}
done

Mosheg, thanks! Can I incorporate this code in bat file? How do I make it execute on demand when called from an ETL process?

In general yes, but the syntax mentioned is for Linux.
You can load files from Windows client, however, for better performance to have parallel load you need to put your files on shared storage where each node on the cluster can access the files.

Thanks mosheg. I think this example can give me direction on how to resolve the issue. The source directory can have multiple files and I need to convert one specific file.