By Alan Boyle, Science Editor, NBC News

EMC2 Fusion Development Corp.

Plasma shines brightly inside EMC2 Fusion's WB-7 device, which was built to

validate earlier experiments in inertial electrostatic confinement fusion.

There's more than one way to do fusion energy research: Some approaches rely on applying well-accepted physics, at a cost of billions of dollars, on a timeline that could stretch out for decades. Other approaches follow unconventional paths that could get to the goal much more quickly, for much less money ... but could also lead to dead ends.

Over the past couple of weeks, the folks following unconventional paths to fusion have signaled that they're a little surer about their progress - while some of the folks following the mainstream path are running into a little more trouble.

Does that mean low-budget fusion will prevail? Not necessarily. But it does mean that fusion research could heat up in the years to come.

Fusion power is so attractive because if it's done right, it could be so abundant. The aim is to bring the same principle that fuels the sun down to Earth: Crush atomic nuclei together to produce bigger nuclei (turning hydrogen to helium, for example), and in the process convert a tiny bit of mass into pure energy (in accordance with Einstein's E=mc² equation).

The mainstream timeline

The deuterium atoms in a gallon of seawater, for instance, could theoretically produce as much energy as burning 300 gallons of gasoline. The fuel contained in 50 cups of water could yield as much energy as burning two tons of coal. The problem is, how do you create a controlled reaction with enough temperature and pressure to get those nuclei fused together?

One way is to blast the fuel with precisely arranged laser beams: That's what the $3.5 billion National Ignition Facility is aiming to do starting later this year, in hopes of creating the first-ever controlled reaction that puts out more energy than it takes in. Last month, Edward Moses, NIF's principal associate director, said it may take a year or two to reach that "scientific break-even" point (as opposed to commercial break-even, which would take more than a decade).

Another way is to heat up a plasma inside a magnetic containment vessel - and then feed it fusion fuel to keep the blast going. That's what the international ITER project is aiming to do at an experimental facility now taking shape in France. However, ITER has been experiencing schedule slips and money problems for the past couple of years.

This month, the director of the U.S. Department of Energy's Office of Science, William Brinkman, reportedly told an advisory panel that ITER was due for a shakeup. "If I could get my hands on the person who proposed the current management structure, I would strangle him," he was quoted as saying.

The current timeline calls for the demonstration reactor to start up in late 2019, with full-scale experiments starting in 2026. But those dates could well slip again, and costs seem likely to escalate. (The most widely used ballpark figure in current usage is 10 billion euros, or $13 billion.)

The alternate timeline

You won't hear Rick Nebel talking about fusion as a challenge requiring billions of dollars and decades of experimentation. For the past couple of years, Nebel heads up a handful of researchers following the less-traveled path to fusion at EMC2 Fusion Development Corp. in Santa Fe, N.M. That path involves creating a high-voltage chamber to sling ions so energetically at each other that at least some of them fuse and release energy.

EMC2 recently created a buzz in the fusion underground by reporting on its Web site that it successfully completed a series of experiments to "validate and extend" earlier results reported by the late physicist Robert Bussard. The company is now using a $7.9 million contract from the U.S. Navy to build a bigger test machine, known as WB-8. (WB stands for "Wiffle Ball," which refers to the shape of the machine's magnetic fields.)

What's more, Nebel and his colleagues are now seeking contributions to fund the development of what they say would be a 100-megawatt fusion plant - a "Phase 3" effort projected to cost $200 million and take four years.

"Successful Phase 3 marks the end of fossil fuels," the Web site proclaims.

Reality check

Success isn't assured. The WB-8 experiment could conceivably show that the approach pioneered by Bussard, known as inertial electrostatic confinement fusion or IEC fusion, can't be scaled up to produce more power than it consumes. And if Nebel's team comes to that conclusion, he doesn't plan to pull any punches.

"No B.S. and no excuses," Nebel told me over the weekend. "If it looks like we have a problem with this, we're going to tell them."

But if IEC fusion actually works, Nebel wants to be ready to commercialize the technology. "Generally what you want to do is have one machine operating, one machine being built, and one machine designed," he said. "We want to be in a position that if we have good results from WB-8, we can hit the ground running."

That's what the contributions being sought under the umbrella of the New Mexico Community Foundation would go toward, he said. Nebel doesn't expect anything near $200 million to start with. "We're just looking for a few hundred thousand to do the design work and do some basic physics on this," he said. "There are some open questions we have to take a look at."

The EMC2 Fusion Web site sports a picture of a 100-megawatt WB-D fusion demonstrator, which looks like a cube about 20 feet on a side. Nebel said the eventual design may not look like the picture, but he does believe the best path to success leads to relatively small-scale reactors rather than the mega-reactors envisioned by ITER's backers.

"The key to making any of these things attractive is being able to make them small," he said.

Nebel can't yet predict whether his path will pan out. Some experts say the equations of plasma physics suggest that Wiffle Ball devices can never produce more power than it consumes, and that IEC research is destined to lead to a dead end. But so far, Nebel sees no reason to stop moving ahead. "It's been quite a trip on this thing," he said, "and I have a feeling this is going to continue."

Other paths less-traveled

Unorthodox paths to fusion have been getting more than their usual share of exposure lately. Several private ventures are searching for shortcuts to commercial power production, and one of them, General Fusion, is profiled this month in hPlus magazine. The Canadian company is working on an approach known as magnetized target fusion, which combines elements of inertial confinement (like the National Ignition Facility) and magnetic confinement (like ITER).

One of General Fusion's prime targets is raising the $50 million (Canadian) it says it needs to build a commercial reactor. So far, the Canadian government has kicked in $13.9 million, and venture capitalists including Chrysalix Energy Ventures have invested another $9 million.

In the hPlus article, General Fusion CEO Doug Richardson says his company's research path is not all that unorthodox. "We're boring," he says. "This is basic stuff, and all we're doing is taking other people's ideas and going down a path that no one has taken yet."

This week, scientists gathered at the American Chemical Society's spring meeting in San Francisco to turn the spotlight on a highly unorthodox path: the effect known as cold fusion.

Back in 1989, cold fusion was heralded as a simple, inexpensive way to get a power-generating fusion reaction on a desktop. But when the experimental results couldn't be reproduced, the researchers were driven into obscurity.

For many physicists, the term "cold fusion" became synonymous with quackery. Chemists, however, have kept up their interest in the effect. This isn't the first time the ACS has hosted a symposium on cold fusion. But the subject's popularity seems to be rising: This year's session featured nearly 50 presentations - including reports on batteries and bacteria that appear to exhibit the cold-fusion effect.

"There's still some resistance to this field," symposium organizer Jan Marwan, of Berlin-based Marwan Chemie, said in a news release. "But we just have to keep on as we have done so far, exploring cold fusion step by step, and that will make it a successful alternative energy source."

Nature's Katharine Sanderson paid a visit to the ACS's cold-fusion news conference - and came away saying she was "still not convinced" that the effect could truly be termed fusion. For that reason, some in the field now prefer the term "low-energy nuclear reactions." New Energy Times' Steven Krivit, who co-wrote a book titled "The Rebirth of Cold Fusion" in 2004, thinks the effect has something to do with weak nuclear interactions but now says "it's not fusion."

Whatever it is, scientists will eventually have to show conclusively that the effect produces more energy than it consumes in order for the wider world to take it seriously as a power source. Come to think of it, that requirement applies to all the paths to fusion ... conventional as well as unconventional.

What do you think? How much time and money should be spent on fusion research here on Earth, especially when you consider there's a perfectly fine fusion source 93 million miles away? Join the discussion by leaving your comment below.

More on the fusion quest:

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Alan Boyle, Science Editor, NBC News