Burj Khalifa, the world's tallest building, is tapping solar power for meeting a bulk of the water heating requirements of residents, Wam has reported. The tower, which was built by Emaar Properties, uses solar panels to heat 140,000 litres of water every day, which will be distributed to homes and commercial entities within the tower, bringing energy savings equivalent to 3,200 kilo watts per day and 690MWh of energy per annum.