That's a good question, which I'm not entirely sure of the answer on to be honest, but I can give some very rough estimates I remember from my I lectures.
I'd say the price EDF is asking for is roughly double the average price here in the UK for nuclear, which is one of the cheapest sources around on the market. Coal and gas I believe sit around £70-80/MWh depending upon the technology and carbon price, but can be cheaper, and we haven't got any good guides for CCS stuff.
Onshore wind is nearing coal and gas at around £80-90MWh and can on a good day be well below this, but offshore is much more, probably more like £120MWh but steadily coming down.
Sorry I don't have better info but hopefully this gives you some idea! EDF will basically be getting a very good deal.