Sydney, Snow machines have used the laws of thermodynamics to paint Beijing’s slopes white for this year’s Winter Olympics. Beijing can seem like an odd place for winter sports. The city receives almost no annual snowfall and the average temperature in the winter month of February is below zero degree Celsius.
Chinese authorities have used more than 350 srow machines to prepare competition venues for the world’s athletes. This has become more common in the last few Winter Olympics, with the Sochi and Pyeongchang Games using 80% and 98% artificial snow, respectively.
But isn’t this artificial snow too expensive? If you own an air conditioner and keep an eye on your energy bill, you will find that stroming takes a lot of energy. Those less knowledgeable in this regard may think of srow machines as giant freezers, fitted with fans, that consume the electricity of an entire city to cover entire mountains with snow.
It’s not really like that. Efficient machines in suitable climates (such as Beijing’s) produce ice per cubic meter of ice using as little as 1.5 kilowatt-hours in Beijing’s climate to produce ice per cubic meter. It’s like you could coat a Sydney apartment in a few inches of snow with the same amount of energy as the air conditioner would use in an hour.
How do Srow Machines Work?
Making artificial snow is not a chemical recipe. The slopes prepared for this year’s events are covered in layers of pure frozen water. Basically, ice machines work using a thermodynamic law, which takes advantage of the natural cooling that occurs when the water evaporates. And because their cooling power comes from evaporation, they can operate at relatively warm temperatures up to 1 °C (provided the humidity is low enough).
It works like this. Ice makers expel a fine water mist in a cold, dry environment. Some of the water in each drop quickly evaporates, taking away the heat and lowering the temperature of the rest of the drop below its freezing point. This process is known as “evaporative cooling”, and is the same mechanism that cools us down when we sweat.
Since this process uses evaporation to make ice, ice machines do not need to expend energy to freeze water. They only need energy to power the fans and compressors that disperse the water droplets.
However, as any Winter Olympian will tell you, snow is much more than just frozen water, and row machines should create powder-like soft snowflakes for the world’s greatest athletes.
The ice formed in this process is not the same as real ice, as artificial ice forms quickly from liquid droplets rather than from water vapor. As a result, the particle size of artificial snow differs from that of natural snow.
As our climate warms and weather patterns change, we are increasingly relying on artificial snow to meet the demands of holiday snow enthusiasts and sportspeople. These Winter Olympics are the first games to be held on 100% simulated snow. And while sromancing is not as environmentally destructive as it may seem at first glance, it is not without drawbacks.
First of all, artificial ice is made of water, which is undeniably an important resource. The International Olympic Committee (IOC) report for this year’s Games estimated that the city of Zhangjiakou, the center of the Beijing Games, will use 730,000 cubic meters of surface water (about 300 Olympic-sized swimming pools) for sromiking alone.
The amount of water to be used throughout the Beijing region will be enormous (although significant efforts are being made to conserve water after the snow melts, and the use of excessive amounts of drinking water for ice making is also avoided Has gone).
Second, hot climates require chemical additives to help ice form and stay frozen. And while these are not actively poisonous, there are still doubts about their safety.
Lastly, srow machines produce a lot of ice. Early reports in the Chinese media claimed that only 200,000 cubic meters of water would be needed to make ice. But the IOC’s pre-game report indicates that the figure is above 800,000 cubic meters.
According to the IOC, this electricity demand in Beijing is being met through 100% sustainable generation. This is encouraging, and is expected to help accelerate the global adoption of eco-friendly technologies.
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