How to define idle delay on Ubuntu desktop

Define idle delay (blank screen) on Ubuntu desktop.

By default idle delay (blank screen) can be set from 1 to 15 minutes, or simply disabled.

Get current idle delay (blank screen) value using seconds.

$ gsettings get org.gnome.desktop.session idle-delay

uint32 300

Disable idle delay (blank screen).

$ gsettings set org.gnome.desktop.session idle-delay 0

Set current idle delay (blank screen) to 20 minutes.

$ gsettings set org.gnome.desktop.session idle-delay 1200

Yes, you can use different values and those will be reflected correctly inside GNOME settings.