Heathrow Airport had enough power to avoid shutdown after fire, Britain's National Grid says
1. Heathrow Airport closed after a fire at an electrical substation. 2. National Grid confirmed other substations had capacity to power Heathrow. 3. Over 1,300 flights were scheduled on the day of the incident. 4. Heathrow's shutdown is expected to cost airlines millions. 5. IATA criticized Heathrow's infrastructure reliance on a single power source.