designs

The race for fusion power

December 9, 2024 By EarthWise Leave a Comment

The sun is powered by fusion energy. Hydrogen atoms fuse together into helium atoms, liberating vast amounts of energy in the process. Our understanding of this process emerged early in the 20th century and by the 1950s, research efforts were underway trying to replicate the process on Earth. If it could be done, fusion would be a source of almost unlimited clean energy. But there has been a cynical saying going around for half a century: fusion power is the energy source of the future, and it always will be.

However, in recent years, there has been progress in developing fusion power. Extraordinarily expensive and colossal machines have produced fusion energy albeit consuming more energy than they make. However, for a brief moment in 2022, a fusion reactor at Lawrence Livermore National Laboratory did produce more energy than it took to run the machine.

Despite the less than encouraging history, there are now multiple start-up companies dedicated to developing fusion energy and they are optimistic that there will be significant progress over the next few years.

One such company, Commonwealth Fusion Systems, located 40 miles northwest of Boston, is building a fusion reactor called SPARC, that they claim will be producing net energy in 2027. They say that their next machine, called ARC, will generate electricity for paying customers in the early 2030s.

A handful of other companies, including Type One Energy, Thea Energy, Realta Fusion, Zap Energy, General Fusion, and Helion Energy are also pursuing fusion reactor designs and also expect to have machines running over the next 5 to 10 years.

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The Quest to Build a Star on Earth

Photo, posted April 21, 2015, courtesy of John Spiri via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

An Electric Cruise Ship | Earth Wise

July 31, 2023 By EarthWise Leave a Comment

The shipping industry accounts for about 3% of global manmade greenhouse gas emissions. In 2018, the International Maritime Organization, the UN body that regulates global shipping, set a target to cut the industry’s greenhouse gas emissions by at least half by 2050.

This goal has led to a variety of designs for eco-friendly ships, including car carriers, superyachts, and cargo ships with retractable sails. But most of the designs still rely to at least some extent on engines that run on fossil fuels.

The Norwegian cruise ship company Hurtigruten has announced that it will build a zero-emissions electric cruise ship with retractable sails covered in solar panels. The ship is expected to set sail in 2030. Hurtigruten is a relatively small company, with a fleet of eight ships, each with a capacity of 500 passengers. But the company hopes that its innovative plan will inspire the entire maritime industry.

The ship will predominantly run off of electric motors powered by 60 megawatt batteries that can be charged in port with renewable energy. To reduce reliance on the battery, when it is windy, three retractable sails will rise out of the deck, reaching a maximum height of 164 feet. The sails will be covered in solar panels that will generate energy to top off the batteries while sailing.

The ship will have 270 cabins to hold 500 passengers and 99 crew members. The streamlined shape of the ship will result in less air resistance to further reduce energy use.

Hurtigruten already has a hybrid, battery-supported cruise ship and is currently in the process of converting its entire fleet to hybrid battery power.

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An electric cruise ship with gigantic solar sails is set to launch in 2030

Photo, posted January 15, 2023, courtesy of Bernard Spragg via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Polar Bears and Tires | Earth Wise

January 12, 2023 By EarthWise Leave a Comment

There is lots of interest in traction. People want to find better ways to move across wet and frozen surfaces safely. This applies to both the shoes on our feet and the tires on our cars.

Researchers at the University of Akron along with colleagues at Syracuse University and at Bridgestone, the tire company, have been studying how many arctic animals can walk and run across the ice without slipping and falling. Their research focused on the paws of polar bears.

Previous studies discovered that polar bears have papillae – little bumps on the pads of their feet – that provide improved traction on snow. The new research also looked at the paws of other species of bear – brown bears and black bears – and found that these others also have papillae on their paw pads, but that those of polar bears are as much as 50% taller. These taller bumps give the pads a 30-50% increase in frictional shear stress.

The research may lead to various applications. For example, snow tires typically have deeper treads, but the polar bear study may lead to some new designs that would improve traction. People who do high-altitude climbing are interested in the research as are companies that deliver goods in bad weather. Anyone who has to be out and about in bad weather would like to get a better grip.

There are various other animals with traction-improving adaptations that are probably worth studying. These include dogs, wolves, foxes, and mountain goats. The same researchers at Akron have also studied other animals with unique abilities to deal with challenging surfaces including geckos, spiders, and mussels. The natural world is filled with examples of creatures who can easily function in environments that we humans find very challenging.

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UA researchers’ focus on tire traction leads to investigation of polar bear paws

Photo, posted March 2, 2008, courtesy of Sam Weng via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.