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Fusion energy

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Nuclear fusion is the process that powers the sun.  Two atoms of hydrogen unite to form one helium atom and release energy in the process.  Hydrogen bombs work in this way and since their development in the 1950s, scientists have sought a way to use fusion to generate electricity.  Many scientists believe that the key to a fully decarbonized future is a combination of solar, wind, and fusion power.

Nuclear fusion does not involve radioactivity and thus does not have the dangers associated with the nuclear fission used in existing power plants.  Over the decades, billions of dollars have gone into fusion research, but the challenges faced in peacefully triggering a fusion reaction have made success always seem to be extremely far off in the future.

The world’s largest fusion project – the International Thermonuclear Experimental Reactor or ITER – was initiated in 1985.  The project involves 35 countries, and the reactor, still under construction in France, has yet to deliver any tangible results.

In the past couple of years, there have been important demonstrations of new and different ways to create nuclear fusion.  A system using laser fusion achieved fusion ignition, in which a reaction briefly became self-sustaining.  A system using magnetic confinement fusion produced a plasma that generated 11 megawatts of power for a world-record five seconds.

There are more than 30 companies competing in the race to deliver fusion energy.  Governments and private investors are funding efforts around the world.  Whether any of them will succeed remains to be seen.  The challenges are immense but so are the potential rewards.

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Will Tech Breakthroughs Bring Fusion Energy Closer to Reality?

Photo, posted July 31, 2010, courtesy of Steve Jurvetson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Grid-Scale Gravity Energy Storage | Earth Wise

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As wind and solar energy play a growing part in our energy system, the need for grid-scale energy storage is growing as well.  An historic form of energy storage and still the largest in installed capacity is pumped hydro storage, which makes use of the potential energy contained in having water sitting at a higher elevation where it can be released downward to operate turbine generators.  This is an effective system but is limited to places where geography cooperates.

For the past five years, a company called Energy Vault has been developing a system that uses the same principle to generate electricity but instead of pumping water to a higher elevation, it uses mechanical devices to lift heavy objects such as concrete blocks to an appropriate height.  Lowering the blocks back to the ground drives generators.

To date, Energy Vault has only built demonstration systems with a fraction of the storage capacity needed for grid-scale operation. Their EV1 Tower in Switzerland was successfully grid interconnected in 2020 and demonstrated round-trip efficiency (the fraction of the energy stored that was produced by the generators) above 75%.  Their improved EVx system is expected to do better than 80%.

This year the company, along with partners Atlas Renewable and China TIanying, is now in the first phases of commissioning a grid-scale system located outside of Shanghai, China.  The 25-MW system is built adjacent to a wind farm and a national grid interconnection site

This is the first grid-scale gravity energy storage system and is expected to be fully online in the fourth quarter of this year.  A second, similar system is now under contract to be built elsewhere in China.

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First grid-scale gravity energy storage system undergoes commencement in China

Photo courtesy of Energy Vault.

Earth Wise is a production of WAMC Northeast Public Radio

A New Fishway Technology | Earth Wise

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Freshwater fish populations have declined by more than 80% over the past forty years across the globe.  This is in part due to hundreds of thousands of dams, weirs, and barriers stopping their movements.  These river barriers have disrupted fish reproduction cycles the world over by preventing river fish from migrating to spawn.

Fishways or fish ladders are waterways constructed on or around obstructions in order to provide passageways for fish and other aquatic species.  Often, they consist of a series of small overflow weirs and pools constructed in the form of steps.  Fish need to jump from one pool to another to migrate to the upstream.  Such fish ladders require a large space to construct.  These and several other types of fishways tend to be expensive to install and maintain and are not always successful in allowing fish to get to where they need to go.

Researchers at the University of New South Wales in Australia have come up with an ingenious new type of fishway.  Called a “tube fishway”, it is a low-cost and low-energy installation that works by pumping fish at high velocity – protected by a cushion of bubbly water – through a tube running over the obstructing barrier to deliver them safely into the water on the other side.

They successfully demonstrated a prototype system on a rugged slope behind a campus building that transported fish from one tank to another about 25 feet up the slope.

Fish are attracted into the chamber by suitable geometry and the system uses the energy available from the upper reservoir to lift the fish.  Modeling shows that the system will work for pipes as large as three feet in diameter and could lift fish more than 300 feet vertically. 

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New fishway technology to get fish up and over those dam walls

Photo, posted October 19, 2019, courtesy of Andrew Harvey via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Extreme Heat From Solar Power | Earth Wise

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Renewable sources are playing a growing role in meeting our energy needs, but one place where they have continued to fall short is in industrial processes that require extreme heat.  These include the cement, steel, and glass industries, among others.  These industries account for a significant amount of CO2 emissions because the most effective way to reach the necessary temperatures continues to be combustion of fossil fuels.  The cement industry alone accounts for 7% of global emissions and the need for cement continues to grow.

A previously stealthy startup company backed by Bill Gates and fellow billionaire Soon-Shiong has made a breakthrough in the area of using solar energy to achieve high temperatures.  The company, called Heliogen, has created a solar oven that is capable of generating heat above 1800 degrees Fahrenheit, which is enough for high-temperature industrial processes.

The Heliogen technology uses concentrated solar power to generate heat.  Concentrated solar power uses arrays of mirrors to reflect sunlight and focus it to a single point.  That technology is not new;  there are systems that use it to produce electricity and, to some extent, heat for industry.  But it could not achieve high enough temperatures for producing cement or steel.

The new system uses computer vision software, automatic edge detection and other sophisticated technologies to focus the sun’s rays far more finely than ever before and thereby generate far higher temperatures at the focal point.

Heliogen is now focused on demonstrating how the technology can be used in a large-scale application, such as cement-making.  The selling points to industry are that not only will there be no emissions generated, but that the fuel needed to obtain their extreme heat will be free.

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Secretive energy startup backed by Bill Gates achieves solar breakthrough

Photo courtesy of Heliogen.

Earth Wise is a production of WAMC Northeast Public Radio.

WAMC Northeast Public Radio

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