They showed that just one heavy-duty tugboat can make the trip in about 140 days while dragging an iceberg weighing 7 million tons - enough to meet the annual water consumption of 35,000 people.
Twelve machines weighing 13 tons carry up to 36 cleaners, who use ordinary soapy water to wash down the Burj's 24, 830 reflective windows in a process that takes three months from top to bottom.