We’re seeing increasingly more complex buildings throughout the world. It stands to reason then that the technology used to maintain a comfortable temperature is equally complex! How is the tallest building in the world protected from its desert surroundings? What natural and technological measures do we combine to keep buildings cool?
More importantly, in a world ever-more concerned with climate change, how are these technologies used with global warming in mind?
The world’s tallest building
The Burj Khalifa towers over Dubai at 2,716.5 feet tall, basking in the desert heat of around 41°C. Keeping a tower this tall cool is a task in and of itself, let alone with the surrounding temperature being so extreme. So, how do they do it?
There’re multiple factors that keep the Burj Khalifa comfortable. Primarily, ice-chilled water is used to cool the building, and this is supplied by three plants. During off-peak hours, the central water plant creates an ice slurry that makes the water colder than a chiller could manage. This chilly water is sent through the tower in a series of pipes to heat exchangers at three different levels. Once the cold water has cooled the air for the air conditioning unit to use, it is sent back down to the central water plant again.
Using ice has a few key benefits:
- It is better for the environment, as it allows the tower to make savings on energy use
- It reduces the amount of space needed to dedicate to cooling equipment
Interestingly, the air conditioning system had to be gradually activated over a week-long period. This was to prevent pockets of warm air from forming in the building.
As a back-up, the tower also has four air-cooled chillers to support the data centres if needed.
A view for all seasons
The British Airways i360 gives visitors a 450-foot sky-high view of the spectacular Sussex coastline. As the world’s tallest moving observation tower, this building set a new challenge for climate control — the structure houses a restaurant, a shop, conference rooms, exhibition spaces, wedding venues, and of course, a 360° panoramic view in its moving 94-ton pod.
The i360 makes use of Daikin VRV IV systems, which supplies the public areas with renewable energy for heating. A constant supply of fresh air is circulated by heat recovery ventilation units throughout the building — this is crucial for reducing the demand on the air conditioning units that need to balance the indoor temperature with a significantly different outside temperature.
Of course, the beach-based building has additional needs for all of its components, due to its surroundings. One, the units need to be out of sight. Two, they need to be able to withstand the corrosive nature of salty sea air! Therefore, the VRV IV outdoor units have been installed out of sight, and are treated with a specialist factory-applied Blygold coating, to protect them from the salt in the air. The result is an energy-efficient, streamlined, and sea-air-ready HVAC system that supports this complex and unique building.
Can I borrow that?
The phrase “waste not, want not” did not go amiss with the Amazon offices in Seattle. The building is heated by capturing the warm air produced by data centres — a great way to re-use waste for a key purpose!
Interestingly, the data centres being used aren’t actually owned by Amazon. The heat is collected from the Westin building across the street from their offices. It’s a two-fold victory, as it helps Amazon to save energy and gives Westin a good way of sustainably dealing with waste heat.
The heated water is piped from the data centres to a central plant belonging to Amazon, and is put through heat-reclaiming chillers. This is then used to supply the office’s heating needs, and the now-cold water is sent back to Westin to help cool their data centres. Amazon is set to save 65 million pounds of coal’s worth of CO2 emissions over 25 years with this approach.
What the future holds
As our building projects seem to get bigger and bigger, so too do our climate control plans for these structures. The Independent reported on another ambitious project blossoming in Dubai — the world’s largest shopping centre. But calling it a shopping centre seems a little unfair; the project intends to cover 48 million square feet, making it a shopping city.
The Mall of the World is set to have the world’s largest theme park, a shopping area inspired by Oxford Street, and a theatre area inspired by Broadway. Crucially, it is being touted as the first climate-controlled city in the world.
Will we continue to see a blend of natural and technological measures to heat and cool our buildings? The world’s structures are only going to get more complex, so it will be interesting to see how requirements like heating and cooling are addressed in such builds.