Currently in the process of decorating daughters bedroom and she has mentioned having a TV on the wall.
So perhaps this year or next we might buy her a TV and wall mount it.
So whilst I am in here now I would like to run a cable up the wall to later be connected to a socket halfway up the wall
Is there any decent solution for having it in the wall hidden so I don't have to have a random socket halfway up the wall before there is a TV to hide it ?
I think you mean you want to run the power (twin and earth) cable from an existing socket, up and inside the wall, terminating also inside the wall, which can later be pulled out and made good into a socket?
Depends on wall construction. If you want to remain compliant/legal, then strictly speaking no. Any
power cable which has a join or terminates (ends) inside a wall, I was under the impression must then be serviceable. So this would need an exit hole with at least a single socket sized blanking plate over the top, which could be removed and then maintenance take place, for in the event of shorts etc. So it may as well be terminated into an actual socket at that point.
It would also be hard to stash enough cable inside the wall if it was solid wall (requiring chasing) to then plaster over and tuck all back in anyway. You'd need a bit of length to pull out, strip and connect up to a socket properly.
If it is an internal wall with cavity that may be easier.
Essentially, if you want to do this and leave it truly inside the wall, then yes it's possible just by having the cable in there but capped off so it could not conduct anything. You could even leave it not connected to the source socket you are spurring off for added safety.
To answer the question, no, there is no "solution" as such to what you are doing that I know of. It would be a temporary solution as described above. A socket half way up a wall doesn't even look that bad anyway. Might as well just get it done if you know a TV will cover it eventually?