Airline stocks down as Heathrow boss warns power supply upgrade could cost £1bn

(Sharecast News) - London-listed airline stocks were on the descent on Friday after Heathrow's boss warned that the cost of upgrading the airport to a new power system could cost upwards of �1bn, with airlines having to foot the bill through landing charges.

The comments came just a week after Heathrow had to close due to massive fire at an electricity substation, which caused a power outage at the world's second-busiest airport.

Heathrow was forced to close its doors to passengers on 21 March and cancel more than 1,300 flights, with further cancellations and delays occurring over the following delays.

Heathrow's engineers had to reconfigure power supplies and conduct safety tests - a process which took more than 24 hours - before the airport could reopen, though the boss of National Grid claims that two nearby substations could have provided enough power for the travel hub to remain open.

In an interview with the Financial Times on Friday, Heathrow chief executive Thomas Woldbye said the airport is now looking into whether a "fully resilient" power system could be installed that would allow it to switch between power sources.

"How far up the supply chain do we need to go, and how much would that cost? That's a dialogue we have to have with our airlines, because they are deeply involved in our investments [...] which has an influence on our charges," Woldbye said.

The funds - which he estimated could be more than �1bn - would likely be raised through the landing charges that Heathrow imposes on airlines to pay for capital expenditure under its regulatory model.

IAG, easyJet and Wizz Air were trading 4.3%, 2.1% and 4.9% lower by 1505 GMT.