Anyone knows if these smart energy meeters from Elko can connect directly to the ST?
Online-komponenter - ELKO
It seems like they are communicationg with the Elko Gateway using Zigbee
They cannot.
The Zigbee profile that SmartThings uses allows for only one coordinator per network, which is the SmartThings hub. The Elko is on a different Zigbee network, so cannot also join SmartThings.
In some cases utility companies provide a web interface to their smart meter accounts and you can sometimes get access that way.
Or in a few cases there is a third party device you can add to the smart meter account which can report over to SmartThings.
Contact the utility company that provided the smart meter and ask them if there is any way to integrate it with your home automation system and see what they say. 
Thanks, seems like this might be a Schneider product that is re-branded:
Yeah, it doesn’t really matter who makes it. It can’t be on two Zigbee networks at the same time. So if it’s on the power company’s network it cannot be added to a smartthings network.
So unless you have built your own power network and you are just looking to add that device, you have to go through the power company to get the information from the device.