Cannot access ubuntu's enviroment variables from PHP

I'm making a codeigniter website and i need to switch configs between production and development. By default Codeigniter searches for the var 

Code:

CI_ENV

 in PHP's 

Code:

$_SERVER

 superglobal. However when i'm trying to set my own with 

Code:

$ CI_ENV=production
$ export CI_ENV

in my production server.
When i'm trying to access it from 

Code:

$_ENV

, 

Code:

$_SERVER

 or 

Code:

getenv()

 it's not there.
Any ideas why?

Are you talking about running via CLI?

ci-phpunit-test | CodeIgniter Testing Guide | CodeIgniter 3 to 4 Upgrade Helper