Home monitoring and auto dehumidifier automation

I would like to start and need some advice.

I want to monitor my electric usage for the whole house maybe a UK sutiable energy monitor I can connect such as z-wave. Must be ok for UK voltages etc…

Next I need to monitor the humidity in 3 rooms and switch on plugs with dehumidifiers connected when humidity levels reach a pre-set level.

I like the look of the Samsung Smartthings if I can get it to work as I want.

This is only to start so it needs to be further expandable with descrete door sensors.