Hi Chris,
There are two issues here:
1. Electricity in Europe - all of Europe (which includes the UK) has a standard mains voltage (230V / 50Hz) which is legally allowed to vary by +5% and -10%.
All modern appliances, such as a TV, will work within these supply tolerances. But you may experience the odd brown out on camp sites if too many people use too much power and slug the site power.
So your UK TV will switch on and operate safely.
2. But what signal will it receive?
If you were expecting to pick up UK analogue or digital (Freeview) services via a roof aerial - then forget it - TV is broadcast on a line of sight basis - and the nearest UK TV transmitters are way over the horizon (with the possible exception of the "Pas de Calais")
If you speak other languages, then can your TV receive those broadcasts? Probably not. The UK uses one PAL standard, France another, etc., and unless you have a multi-standard TV - it just won't display an image.
If you are going to take a UK satellite disk with you - then you'll be outside the primary reception area (the UK) of the satellite, and a larger (than standard) dish is needed.
Robert