Get server timezone In PHP

Question

My client need a system report of the server information for his plugin running, hence I must obtain the SERVER timezone. utilizing Wordpress. I tried this, however not all servers are compatible.

$date = new DateTime();
$date->setTimezone(new DateTimeZone(ini_get('date.timezone')));

On some servers, this results in a catastrophic error. Is there a widely used function to determine the server timezone?
We would much appreciate any advice.