Electricity in France is generally cheaper than in the UK because most of it is generated through nuclear power stations. This means that the French energy market there is not as open to the volatility of wholesale energy prices. Last year, in the UK, wholesale energy costs rose by over 200% - whereas our own prices only went up by 26% (gas).
Getting our electricity supplies from France would be fine – if we all lived in the South East of England. Unfortunately, the more miles energy has to travel through cables and wires, the more power it will lose.