* Project to lower costs, improve security of supply
* French power prices around 30 pct lower than Britain (Updates with comment, start date, background)
PARIS/LONDON July 21 (Reuters) - France and Ireland plan to build a 1 billion euro ($1.10 billion) cable which would allow electricity to flow between the two countries by 2025, Ireland’s grid operator said on Thursday as French President François Hollande visited the country.
Ireland currently imports electricity from Britain via Northern Ireland but is looking for ways to increase its electricity supplies.
The planned 600-km link will run between Brittany and the south coast of Ireland.
“The (interconnector) will improve security of supply on the island of Ireland and increase competition, driving down prices for customers,” Fintan Slye, EirGrid Chief Executive said in a statement.
French average spot prices on power exchanges were around 30 percent cheaper than those in Britain last year, according to data from French power grid operator RTE.
If built, the 700 megawatt (MW) sub-sea cable could transport enough electricity to power around 450,000 homes, Eirgrid said.
The project has been at the planning stage for several years but on Thursday moved to an initial design an pre-consultation phase launched by Ireland’s prime minister Enda Kenny and French President François Hollande during his visit to Ireland.
Eirgrid said this phase would take around two years and include an economic, technical and environmental assessment of the project.
If a decision was taken to move forward with the project it could be carrying electricity between the two countries by 2025, Eirgrid said. ($1 = 0.9076 euros) (Reporting by Bate Felix in Paris and Susanna Twidale in London, editing by Sybille de La Hamaide and David Evans)