Thursday, December 19, 2019

Airships Offer Both Climate Mitigation and Adaptation

Varialift solar powered airship concept
The emissions associated with traditional air travel make airships an ideal low-cost alternative for shipping. Compared to traditional transportation mediums, airships are quiet, cheaper to operate, and most importantly, far more carbon efficient. They also have a much larger range and cargo carrying capacity. While slower then jet powered aviation, they are faster than current land or sea transportation systems (airships travel at speeds of up to 120 kilometers an hour or around 70 miles per hour).

Many shipping routes could be serviced by airships. A 2016 study found that as much as half of the air cargo between Hong Kong and the U.S. and Europe could be replaced by airships. Because airships float using lighter-than-air gas (hydrogen or helium) they do not require fuel to maintain flight and they can carry massive payloads. They can carry loads weighing 500 tons or more. This means it will not be necessary to dissemble something before it is shipped. Airships can also avoid congested airports and shipping ports. All of the above saves energy, time and money.

Airships not only mitigate against climate change they can also help us to adapt to a warmer world. Although their size makes airships vulnerable to bad weather, modern technology should enable them to avoid such weather. In places like northern Canada airships can replace ice roads that are increasingly less safe due to warmer temperatures. When extreme weather strikes airships are an ideal transportation medium to provide humanitarian relief as they do not need air or sea ports.

There are several types: Non-rigid (a blimp), or semi-rigid (with a partial supporting structure), or rigid (with a complete supporting structure). There is also the hybrid airship, which uses traditional wings or rotors to provide lift and control.

What makes an airship so compelling is the fact that they are radically efficient and have little or no emissions. When powered by fossil fuel engines they produce up to 90 percent fewer emissions compared to conventional aircraft. However, air ships can also be paired with fuel cells and solar powered electric motors.

According to a paper in the journal Energy Conservation and Management an airship traveling in the stratosphere could move 21,000 tons of stuff using almost no energy at all. Airships propelled by the winds of the jet stream could move at speeds of between 100 and 250 mph. Such an airship could travel from Denver to China in about seven days or from Los Angeles to Tokyo in four.  However, we have yet to develop the flexible materials that are required to make such flights possible.

There are other downsides, hydrogen is flammable and helium is both non-renewable and expensive. Nonetheless, forward looking governments would be wise to make investments in research and development.

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