FUTURE ENERGY eNEWS

 Integrity Research Institute                                       DECEMBER 2014

By Evan Ackerman  IEEE SPECTRUM  DECEMBER 2014 

http://spectrum.ieee.org/energy/nuclear/inside-the-dynomak-a-fusion-technology-cheaper-than-coal

  Modifying the most common type of experimental reactor might finally make fusion power feasible

Fusion Power  has many compelling arguments in its favor. It doesn't produce dangerous, long-term toxic waste, like nuclear fission. It's far cleaner than coal, with a supply of fuel that's virtually unlimited. And unlike with wind and solar, the output of a fusion power plant would be constant and reliable.

The primary argument against fusion power has been that despite decades of work, it still doesn't exist. But that's no hindrance to a fresh crop of enthusiasts from academia, government, private industry, and even venture capital firms.

In October, Lockheed Martin Corp. revealed that it's been working on a type of fusion reactor that could be made small enough to transport by truck.Lawrenceville Plasma Physics raised money through crowdfunding in June to advance its alternative proton-boron fusion. Helion Energy is developing a type of fusion based on magnetic compression, and General Fusion is working toward a power system that involves shock waves inside a vortex of liquid metal.

A particularly promising approach was unveiled recently by a University of Washington research group, led byplasma physicist Tom Jarboe. They've been developing a type of fusion reactor called a dynomak. The researchers involved say the technology is unique in that it offers a path to a power plant that's backed up by demonstrated physics and because such a reactor also promises to be even more economical than a coal-fired power plant.

The dynomak is a variation of the most popular type of research fusion machine, the tokamak. Essentially, a tokamak is a doughnut-shaped machine that generates helical magnetic fields by combining toroidal fields (which go around the doughnut's equator) with poloidal fields (which wrap around the outside of the doughnut). These fields have to be strong enough to keep plasma stable and contained indefinitely at the tens to hundreds of millions of degrees Celsius necessary to induce fusion.

In practice, tokamaks are hollow, doughnut-shaped vacuum chambers with interior walls made of heat-resistant metals or ceramics. Outside the chamber are massive superconducting coils that generate the toroidal magnetic fields that stabilize the plasma. The European Union, China, India, Japan, Russia, South Korea, and the United States are collaborating to build a giant US $50 billion tokamak in France called ITER (originally International Thermonuclear Experimental Reactor), which may lead to a fusion power plant in the 2030s. But the University of Washington group-and its alternative-fusion competitors-are hoping to beat it to commercialization.

The University of Washington's dynomak is a refinement of a subtype of tokamak called a spheromak. The most important difference is that the spheromak does away with most of the tokamak's expensive superconducting magnetic coils. Instead, a spheromak uses the electric currents flowing though the plasma itself to generate the magnetic fields needed to both stabilize and confine the plasma.

This is tricky, as UW graduate student Derek Sutherland explains. For it to work, you need not only a sophisticated understanding of the physics underlying the behavior of the plasma but also a very efficient way of driving the current. If you're not careful, you'll end up dumping all the energy that your reactor is producing right back into the plasma just to keep it contained-resulting in a very expensive machine that will power itself and nothing else.

According to Sutherland, the big breakthrough was UW's experimental discovery in 2012 of a physical mechanism called imposed-dynamo current drive (hence "dynomak"). By injecting current directly into the plasma, imposed-dynamo current drive lets the system control the helical fields that keep the plasma confined. The result is that you can reach steady-state fusion in a relatively small and inexpensive reactor. "We are able to drive plasma current more efficiently than previously possible," says Sutherland. "With that efficiency can come higher current and a more compact, economical design."

How economical? According to projections by Sutherland's group, a dynomak has the potential to cost less than a tenth as much to build as a tokamak like ITER, even as it produces five times as much power. This massive boost in efficiency is very compelling: According to UW's analysis, it makes the total cost of a dynomak fusion power plant with an output of 1 gigawatt slightly cheaper than the total cost of a coal power plant with the same output-$2.7 billion versus $2.8 billion.

The UW researchers are particularly optimistic about their dynomak because it's not much of a deviation from established systems. "I think we've blended the mainstream and alternates into a pathway that is completely plausible but different enough to really start addressing the economic issues facing fusion power," says Sutherland.

"The spheromak-and the dynomak is a species of spheromak-in particular has not received the level of attention that it warrants," says University of Iowa physicist Fred Skiff. "The potential advantages are significant: a lower magnetic field-and therefore lower cost and complexity-and a smaller reactor." The lower magnetic field requirements are important because "large superconducting coils are not trivial to produce and protect in a reactor environment."

However, "there are significant unknowns," says Skiff. "The ability to control the current profile, the plasma position, and the ability to maintain high confinement will have to be demonstrated."

The next steps for the dynomak are straightforward. The experimental device Jarboe's group is working with right now, called HIT-SI3, is about one-tenth the size that a commercial dynomak fusion reactor would be. It includes three helicity injectors, which are the coils that control the delivery of twisting magnetic fields into the plasma. "The eventual dynomak reactor will have six injectors according to the current design," says Sutherland. With $8 million to $10 million in funding, the group hopes to construct HIT-SIX, a six-injector machine that will be twice as large as HIT-SI3.

At that size, things start to get interesting, says Sutherland. HIT-SIX is designed to reach millions of degrees Celsius using a mega-ampere of plasma current. If imposed-dynamo current drive works well in HIT-SIX, he'll be "much more confident going forward that our development path will be successful," he says.

That entire path, including an electricity-generating pilot plant, would require about $4 billion, Jarboe's group projects. Compared with ITER's $50 billion, that's a bargain.

FUSION ALTERNATIVES

   LAWRENCEVILLE PLASMA PHYSICS

Funding: $3 million from private investors, plus $180,000 from a crowdfunding campaign on Indiegogo; currently applying for a two-year, $2 million Advanced Research Projects Agency-Energy grant. How does it work? A strong pulse of electricity generates filaments of plasma. The filaments are combined, and natural instabilities cause them to twist into a plasmoid. The plasmoid self-heats to reach a fusion state. What's the advantage? Instead of trying to control plasma instabilities with magnetic fields, the system uses the instabilities to create fusion. Hydrogen-boron fusion reactions do not create radioactive by-products. When will it be commercial? Currently performing test shots to increase plasma density; garage-size 5-MW generators by 2020 costing $300,000 to $500,000 each.

LOCKHEED MARTIN :

Funding: Internal. How does it work? The device [above] is similar to a tokamak, but it uses a new type of self-tuning feedback mechanism to control its magnetic field geometry. What's the advantage? Very efficient reactors will be small enough to fit inside trucks and shipping containers, and they could even power an airplane indefinitely.When will it be commercial? Currently testing operational theories; functional reactor by about 2025.

HELION ENERGY:

Funding: US $7 million from NASA, the Department of Energy, and the Department of Defense, plus $1.5 million in seed funding.How does it work? Plasma fuel forms stable toroids at either end of a chamber. The toroids are then slammed together at more than1.6 million kilometers per hour. What's the advantage? All solid-state electronics make for small, modular power plants. Fusion energy is directly converted to electricity. The plant generates its own helium-3 fuel as a by-product. When will it be commercial?Currently developing a reactor-scale fusion core; 50-megawatt pilot plant in 2019.

GENERAL FUSION:

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By Peter Fairley  IEEE SPECTRUM

John Rogers, Fall 2014, Catalyst, Union of Concerned Scientists, 

http://www.ucsusa.org/clean_energy/our-energy-choices/renewable-energy/solar-power-technologies-and-policies.html#.VIedAst0w1I 

Solar power generates electricity with no global warming pollution, no fuel costs, and no risks of fuel price spikes, and has the potential to help move the country toward cleaner, reliable, and affordable sources of electricity.

Small-scale solar photovoltaic (PV) systems, typically on rooftops, account for the majority of solar installations, while large-scale PV systems and concentrating solar power (CSP) systems constitute the majority of solar's overall electricity-generating capacity.

All three are undergoing rapid growth. Given the abundance of sunshine across the country, solar power has the potential to supply a significant amount of electricity that is both environmentally and economically attractive.

Their increasing cost-effectiveness is largely a result of reductions in technology prices, innovative financing, and growing networks of solar installers and financial partners

Tax credits, rebates, and other support in leading states can cut the total costs of a rooftop system to under $10,000, though many solar customers are paying little or nothing up front by utilizing solar leases or power purchase agreements, which provide electricity from the system over a long period at attractive fixed rates.

Costs for large-scale PV projects have dropped more than household systems, to an average 60 percent lower than those for residential solar on a per-watt basis.

CSP systems have not experienced the same cost reductions, but offer the important advantage of being able to store the sun's energy as heat, and to use it to make electricity when the sun is no longer shining.

Solar power is viable throughout the United States

In a sunny location such as Los Angeles or Phoenix, a five-kilowatt home rooftop PV system produces an average of 7,000 to 8,000 kilowatt-hours per year, roughly equivalent to the electricity use of a typical U.S. household.

In northern climates such as in Portland, Maine, that same system would generate 85 percent of what it would in Los Angeles, 95 percent of what it would in Miami, and six percent more than it would in Houston.

For CSP, the best resources are in the Southwest, though facilities have also appeared in Florida and Hawaii.

·          

• By early 2014, the United States had more than 480,000 solar systems installed, adding up to 13,400 megawatts (MW)- enough to power some 2.4 million typical U.S. households.
• The U.S. solar industry employed more than 140,000 people in 2013, a 53 percent increase over 2010, and is investing almost $15 billion in the U.S. economy annually. There are currently more than 6,000 solar companies in the U.S., spread across all 50 states.
• Companies, too, have embraced rooftop solar not only to improve their environmental profiles but also to lower their operating costs.
• PV systems require no water to make electricity, unlike coal, nuclear, and other power plants. Likewise, solar panels also generate electricity with no air or carbon pollution, solid waste or inputs other than sunlight.

To continue solar power's rapid growth, we must take steps to support its continued acceleration

Important focus areas include:

• Renewable electricity standards. States should maintain and strengthen their key policies for driving renewable energy investments, including solar.
• Solar tax credit. The federal investment tax credit that has been so important for solar's rise is set to decline at the end of 2016 from 30 percent to 10 percent; Congress will need to take action to sustain that support.
• Federal power plant carbon standards. States should ensure that solar plays a strong role in their plans to reduce emissions to comply with the Environmental Protection Agency's new carbon standards.
• The full value of solar. Assessing the full range of benefits and costs of solar, particularly rooftop solar, will help policy makers decide the most appropriate way to assist more people in adopting solar.
• Storage. Lower costs and the greater availability of energy storage technologies will help provide electricity more consistently and at times of peak demand.

• New utility business models. Utilities should modify their business models to accommodate high levels of rooftop solar and encourage continued solar development, from rooftops to large-scale projects.

• Research and development. Solar's prospects will be enhanced by continued progress in reducing costs-through greater economies of scale, increasing cell and module efficiencies, improved inverters and mounting systems, better heat transfer, and streamlined transactions.

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 Katharine Sanderson. New Scientist, 2014

http://www.newscientist.com/article/dn26204-watersplitter-could-make-hydrogen-fuel-on-mars.html#.VIn_U9LF_To

Making fuel on site for a return trip to Mars may be a step closer. A cunning way to split water into oxygen and hydrogen in two distinct steps could be a boon to both astronauts and future Earthlings, enabling them to use renewable energy sources for making hydrogen fuel.

Hydrogen fuel cells can power vehicles ranging from cars to submarines and rockets. They can also heat buildings, and double as portable power-packs for computers or other kit used in the field. But existing methods for creating usable hydrogen gas from water require a lot of electricity. That means renewable energy sources like wind or sunlight, which are often patchy, are not reliable enough.

It can also be hazardous to scale up "artificial leaves", which make fuel from sunlight, just like plants, says Lee Cronin at the University of Glasgow, UK. This is because the low powers available don't produce the gases quickly enough to keep them apart once they form. "All they do is build up oxygen and hydrogen until they explode," he says.

Cronin and his colleagues see this as a major obstacle to a future in which hydrogen fuel replaces oil. To get around it, they built a device that uses a single pulse of power to split water, so continuous energy is not needed.

Catch and release

The device zaps water with electricity to release oxygen, then a silicon-based chemical mediator dissolved in the water mops up stray protons and electrons. When it is full, the mediator turns blue, letting a human operator know it can be removed and stored for later. When the hydrogen is needed, putting the mediator in contact with a platinum catalyst allows those electrons and protons to recombine to make hydrogen gas.

The whole process uses a single whack of power, and patchy renewable energy will suffice for this, says Cronin. In return, he says, 30 times as much hydrogen can be made than from existing systems. The device could find uses generating power in developing countries or for making fuel on Mars to power a rocket back to Earth.  

It is unclear whether Cronin's device will be able to compete with other existing processes, says Steve Reece, a water-splitting expert at Lockheed Martin in Cambridge, Massachusetts. "It will be interesting to see how this concept scales."

Journal reference: Science, DOI: 10.1126/science.1257443

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