PC to TV connection

I have done some research on this but can not find a solution so i hope someone here knows if it can be done.

I have a new flat screen HDTV and it is connected to the internet using "powerline adapter" plus via a decoder (separate connection) to my ISP who deliver my telephony,TV and internet.
My PC also uses powerline so what i am wondering is if i can network the TV with the PC via the powerline internet to be able to show videos from my PC to the TV.
I know i could do it via a HDMI cable but i would like to avoid this if possible because it would entail running the cable across the den floor.
Any help graciously received.

Bill

 

Too late to edit

I am using MS windows 7 pro

 

Update
I am one step closer, the TV can now see the PC but as yet i can not see the TV on the PC and the TV gives the message "failed to connect to server"

 

Due to you mentioning a "decoder", did you read something about XFTA dongle??? That, if I understand it right, is a switch or router wireless that can do that. Just an idea, though...