Featured Research

from universities, journals, and other organizations

Fusion energy: Mug handles could help hot plasma give lower-cost, controllable fusion energy

Date:
October 11, 2012
Source:
University of Washington
Summary:
New hardware lets engineers maintain the plasma used in fusion reactors in an energy-efficient, stable manner, making the system potentially attractive for use in fusion power plants.

A computer drawing of the prototype, which attaches current-carrying handles to either end of the central plasma.
Credit: T. Jarboe, Univ. of Washington

Researchers around the world are working on an efficient, reliable way to contain the plasma used in fusion reactors, potentially bringing down the cost of this promising but technically elusive energy source. A new finding from the University of Washington could help contain and stabilize the plasma using as little as 1 percent of the energy required by current methods.

"All of a sudden the current energy goes from being almost too much to almost negligible," said lead author Thomas Jarboe, a UW professor of aeronautics and astronautics. He presents the findings this week at the International Atomic Energy Association's 24th annual Fusion Energy Conference in San Diego.

The new equipment looks like handles on a coffee mug -- except they attach to a vessel containing a million-degree plasma that is literally too hot to handle.

Most people know about nuclear fission, the commercial type of nuclear power generated from splitting large atoms in two. Still under research is nuclear fusion, which smashes two small atoms together, releasing energy without requiring rare elements or generating radioactive waste.

Of course, there's a catch -- smashing the atoms together takes a lot of energy, and scientists are still working on a way to do it so you get out more energy than you put in. The sun is a powerful fusion reactor but we can't recreate a full-scale sun on Earth.

An international project in France is building a multibillion-dollar fusion reactor to see whether a big enough reactor can generate fusion power.

The reactor in France will inject high-frequency electromagnetic waves and high-speed hydrogen ions to sustain the plasma by maintaining an even hotter 100-million-degree operating temperature and enclosing it with magnetic fields.

"That method works," Jarboe said, "but it's extremely inefficient and expensive, to the point that it really is a major problem with magnetic confinement."

For two decades Jarboe's team has worked on helicity injection as a more efficient alternative. Spirals in the plasma produce asymmetric currents that generate the right electric and magnetic fields to heat and confine the contents. Plasma is so hot that the electrons have separated from the nuclei. It cannot touch any walls and so instead is contained by a magnetic bottle. Keeping the plasma hot enough and sustaining those magnetic fields requires a lot of energy.

"We would drive it until it was unstable," Jarboe said of his approach. "Like you twist up a rope, the plasma twists up on itself and makes the instability and makes the current drive."

Results showed the UW strategy required less energy than other methods, but the system was unstable, meaning that if conditions change it could wobble out of control. It's like a stick balancing on one end, which is stable at that moment, but is likely to come crashing down with any nudge. In the case of plasma, unstable equilibrium means that a twist in the plasma could cause it to escape and potentially lead to a costly reactor shutdown.

Instability was a major impediment to applying the UW method.

"The big issue is whether, when you distort the bottle, it will leak," Jarboe said.

By contrast, in a stable equilibrium, any shift will tend to come back toward the original state, like a ball resting at the bottom of a bowl that will settle back where it started.

"Here we imposed the asymmetric field, so the plasma doesn't have to go unstable in order for us to drive the current. We've shown that we can sustain a stable equilibrium and we can control the plasma, which means the bottle will be able to hold more plasma," Jarboe said.

The UW apparatus uses two handle-shaped coils to alternately generate currents on either side of the central core, a method the authors call imposed dynamo current drive. Results show the plasma is stable and the method is energy-efficient, but the UW research reactor is too small to fully contain the plasma without some escaping as a gas. Next, the team hopes to attach the device to a larger reactor to see if it can maintain a sufficiently tight magnetic bottle.

The research is funded by the U.S. Department of Energy. Co-authors are Brian Nelson, research associate professor of electrical engineering; and research associate Brian Victor, research scientists David Ennis, Nathaniel Hicks, George Marklin and Roger Smith and graduate students Chris Hansen, Aaron Hossack, Cihan Ackay and Kyle Morgan, all in UW aeronautics and astronautics.


Story Source:

The above story is based on materials provided by University of Washington. The original article was written by Hannah Hickey. Note: Materials may be edited for content and length.


Cite This Page:

University of Washington. "Fusion energy: Mug handles could help hot plasma give lower-cost, controllable fusion energy." ScienceDaily. ScienceDaily, 11 October 2012. <www.sciencedaily.com/releases/2012/10/121011151629.htm>.
University of Washington. (2012, October 11). Fusion energy: Mug handles could help hot plasma give lower-cost, controllable fusion energy. ScienceDaily. Retrieved July 25, 2014 from www.sciencedaily.com/releases/2012/10/121011151629.htm
University of Washington. "Fusion energy: Mug handles could help hot plasma give lower-cost, controllable fusion energy." ScienceDaily. www.sciencedaily.com/releases/2012/10/121011151629.htm (accessed July 25, 2014).

Share This




More Matter & Energy News

Friday, July 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Europe's Highest Train Turns 80 in French Pyrenees

Europe's Highest Train Turns 80 in French Pyrenees

AFP (July 25, 2014) Europe's highest train, the little train of Artouste in the French Pyrenees, celebrates its 80th birthday. Duration: 01:05 Video provided by AFP
Powered by NewsLook.com
TSA Administrator on Politics and Flight Bans

TSA Administrator on Politics and Flight Bans

AP (July 24, 2014) TSA administrator, John Pistole's took part in the Aspen Security Forum 2014, where he answered questions on lifting of the ban on flights into Israel's Tel Aviv airport and whether politics played a role in lifting the ban. (July 24) Video provided by AP
Powered by NewsLook.com
Creative Makeovers for Ugly Cellphone Towers

Creative Makeovers for Ugly Cellphone Towers

AP (July 24, 2014) Mobile phone companies and communities across the country are going to new lengths to disguise those unsightly cellphone towers. From a church bell tower to a flagpole, even a pencil, some towers are trying to make a point. (July 24) Video provided by AP
Powered by NewsLook.com
Algonquin Power Goes Activist on Its Target Gas Natural

Algonquin Power Goes Activist on Its Target Gas Natural

TheStreet (July 23, 2014) When The Deal's Amanda Levin exclusively reported that Gas Natural had been talking to potential suitors, the Ohio company responded with a flat denial, claiming its board had not talked to anyone about a possible sale. Lo and behold, Canadian utility Algonquin Power and Utilities not only had approached the company, but it did it three times. Its last offer was for $13 per share as Gas Natural's was trading at a 60-day moving average of about $12.50 per share. Now Algonquin, which has a 4.9% stake in Gas Natural, has taken its case to shareholders, calling on them to back its proposals or, possibly, a change in the target's board. Video provided by TheStreet
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins