Connecting Excel 2016 to Postgres
Postgres data can be used in Excel 2016 but it requires the ODBC driver and an external setup of the database server. As far as I can tell the Npgsql drivers do not work with my version of Excel which is 2016 MSO 32-bit a.k.a "Home Premium".
The Postgres ODBC driver is available here: https://www.postgresql.org/ftp/odbc/versions/msi/ Download and install the latest version. It should install without needing a system reboot.
Setup a DSN (I used machine) using the ODBC Data Sources (XX-bit) setup application. The driver version needs to match your Excel version.
After testing the connection in the setup screen, open Excel 2016 and use the Data -> New Query -> From Other Sources -> From ODBC menu to open the query screens. This seems to be the most modern interface available in Excel.