Energy

Researchers can now image the flow of energy in nuclear fusion ignition attempts

The team integrated copper into the fuel capsule, which led to X-ray emissions that can be captured and analyzed
The team integrated copper into the fuel capsule, which led to X-ray emissions that can be captured and analyzed
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When the laser beam hits the compressed fuel, high-energy electrons are generated – these hit the copper and cause X-ray emissions, which are then imaged to analyze the flow of energy
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When the laser beam hits the compressed fuel, high-energy electrons are generated – these hit the copper and cause X-ray emissions, which are then imaged to analyze the flow of energy
The team integrated copper into the fuel capsule, which led to X-ray emissions that can be captured and analyzed
2/2
The team integrated copper into the fuel capsule, which led to X-ray emissions that can be captured and analyzed

It's fair to say that nuclear fusion is the holy grail of clean energy production, with the potential to provide limitless clean energy, but right now there are a fair few barriers to making it a reality. An international team of researchers has inched the dream one step closer to reality, creating a method by which energy dispersal can be observed during ignition attempts, paving the way for improved energy delivery during the process.

The breakthrough relates to a process known as fast ignition, which is one of the leading approaches focused on achieving controller nuclear fusion. A two-stage technique, it involves using hundreds of lasers to compress a small amount of fusion fuel (a mix of tritium and deuterium) inside a tiny spherical plastic fuel capsule, before employing a high-intensity laser to deliver a second burst of energy that ignites the fuel.

The process is promising, not least because it requires less energy than other approaches, but there are a number of problems that are currently stopping it from succeeding. One of these is the need to precisely direct the second stage laser so that it hits the densest region of the fuel.

When the laser beam hits the compressed fuel, high-energy electrons are generated – these hit the copper and cause X-ray emissions, which are then imaged to analyze the flow of energy
When the laser beam hits the compressed fuel, high-energy electrons are generated – these hit the copper and cause X-ray emissions, which are then imaged to analyze the flow of energy

This is where the new research steps in, providing a way to capture and analyze the dispersal of energy as the laser hits it target. To make that possible, the researchers integrated copper into the inside of the fuel capsule. When the laser beam hits the compressed fuel, high-energy electrons are generated. These hit the copper and cause X-ray emissions, which are then imaged to analyze the flow of energy.

With the knowledge that the imaging provides, scientists can now work on creating new techniques that will improve the delivery of energy to the compressed fuel target. The team has already made significant progress in that regard, trying out different experiment designs, eventually increasing the efficiency of energy delivery by a factor of four over previous tests.

"Before we developed this technique, it was as if we were looking in the dark," said paper co-author Christopher McGuffey. "Now, we can better understand where energy is being deposited so we can investigate new experimental designs to improve delivery of energy to the fuel."

The team's findings were published in the journal Nature Physics.

Source: UC San Diego

5 comments
Gavin Roe
how you going to capture the energy produced, by the same old steam turbine system wasting more than half
Grunchy
No ideal/reversible heat engine can exceed Carnot efficiency, defined as Nth = 1 - Tc/Th where Tc is the absolute cold side temp. The only way such an ideal/reversible heat engine could approach 100% efficiency is if the cold side is held at absolute zero, which is impractical. Anyways, it's kind of mistaken to call this physical inefficiency "waste". It's a physical limit caused by the nature of entropy: the universe seems unable to convert 100kW of disordered heat perfectly into 100kW of ordered power. Physical processes will always create waste heat, tone challenge I suppose could be to find something useful to apply that waste heat towards.
Douglas Bennett Rogers
Combined cycle steam can recover 80% of the energy. Fusion with charged particles could recover well over 80%.
fb36
Steam turbine is not the only option. It may use solar panels and/or thermo-electric systems converting light and heat directly to electricity (which are also not bound by Carnot efficiency issue). I don't think it could use steam turbine anyway since it would produce energy in pulses, not in a continuous way.
Wolf0579
Can anyone say "Waste of taxpayers money"? This project is only going to benefit the existing energy megacorps. The only way this energy would get to a consumer is through a conductor with a meter on it... and who do you think will be collecting the profits... not the public who is paying for this research. Solar, wind, and wave energy should be getting the lion's share of research monies but they're not. Guess why? Your elected "representatives" make a lot of noise about working for their constituents, but they act on behalf of the corporations.