Wind Falters while Nuclear Surges

In Europe and North America, the development of nuclear power effectively halted after the March 1979 accident in Pennsylvania at Three Mile Island. Until recently the building of additional nuclear reactors in most developed nations was unlikely. Meanwhile, the greatest hope of the alternative energy industry has been wind power, but people around the world are starting to question the safety and effectiveness of large wind farms. As the public's infatuation with “green” energy has faded, the resurgent nuclear power industry has been quietly ramping up its efforts to provide the energy the world will need in the future. Even ecological activists have come to realize that nuclear is the only viable option to fossil fuels. As a result, a nuclear surge is underway, with 52 new reactors under construction around the world and more in the planning stages. This about face in energy policy amounts to nothing less than a nuclear renaissance.

Despite growing evidence that the global warming scare was just the latest in a long string of pseudo-science based overreactions, politicians and activists have charted a course of diminishing CO2 emissions for the foreseeable future. But the favorite choices of renewable energy advocates, solar and wind, have fallen on hard times. Recently, activists enlisted the aid of Senator Dianne Feinstein in blocking the development of industrial scale concentrating solar plants in the California desert. This is just the latest action to block alternate energy development, on a scale where it could make a meaningful contribution to the world's energy needs, be it wind, solar or geothermal. Because of several adverse trends, some of the countries that have pushed wind most aggressively may be approaching a saturation point where further turbine investment would be counter-productive.

Even though wind meets 20% of electricity demand in Denmark, 14% in Spain and Portugal, and 8% in Germany, wind power expansion has stalled. Problems with variability and concernes over damage to birds and bats have dampened the public's enthusiasm for this most mature of alternative energy sources. From Austrailia to Scotland, and from Main to California people in increasing numbers are opposing wind power development. And as the public support has waned, the wind industry has suffered.

The Burbo Bank Offshore Wind Farm in Liverpool Bay, England . Christopher Furlong / Getty.

On August 18, after a second straight quarterly loss, the top Danish wind manufacturer Vestas saw the value of its shares drop 20%. While wind currently provides about 2.5% of electricity in the United States, leaving room for significant growth, things are not looking good in the world's largest wind power market. In fact, according to Bill Sweet in an online IEEE article, “After Soaring, Wind Glides,” the outlook in the US is decidedly gloomy:

A more sober mood has settled over the wind industry this year. In the United States, where 10 gigawatts of capacity was added in 2009, up a record-setting 20 percent from the previous year, new turbine installations this year are expected to be closer to 6 GW.

More bad news comes from the independent business intelligence service Wind Energy Update. The WEU's Wind Energy Operations & Maintenance Report found that current operation and maintenance (O&M) costs are two or three times higher than first projected and that there has been a 21% decrease in return on investments from wind farms. O&M costs were found to be especially high in the United States. The report states that while close to 80% of the world's wind turbines are still under warranty, “this is about to change.” Ongoing wind turbine development is focusing on gearbox reliability: “Many gearboxes, designed for a 20-year life, are failing after six to eight years of operation.”

The US Department of Energy (DOE) registered a rather sharp increase in “wind curtailments” during 2009. A curtailment is an order to generators to stop feeding energy into the grid. They can happen because demand is low or transmission lines can't handle the load. Regardless of the cause, US wind capacity factor—a measure of the time a wind generator is producing at its maximum possible rate—dropped to 30% from 34% the previous year. This means in effect that for every watt of coal, gas, or nuclear capacity installed, about three times as much wind capacity has to be built to deliver equivalent output over time. Enter the nuclear renaissance.

In a thoughtful article in the August 13, 2010, issue of Science, Robin W. Grimes and William J. Nuttall identify the questions that must be answered for the new nuclear renaissance to succeed. They see the coming nuclear rebirth as a two-stage process: replacing or extending the life of existing nuclear power plants in the short term, and a large-scale second period of construction after 2030. They identify the key major problems to be overcome this way:

If the global electricity system is to be largely decarbonized over the first half of this century, then two key challenges must also be surmounted. One will be to develop civil nuclear programs in all parts of the world without risking the proliferation of nuclear weapons technologies. The other will be to deal with nuclear waste in as safe a manner as possible. Settling on policy options has proved extremely difficult in many countries for many decades. Technical proposals are available, including deep geological disposal. The assessment and perception of the risks associated with the transport and storage of radioactive wastes will continue to be reconsidered, given growing concerns about unconstrained fossil fuel wastes being emitted into the atmosphere. Newer reactor designs have the promise of creating less waste or waste that has a shorter lifetime, but some storage issues will still need to be resolved.

While Grimes and Nuttall are strongly motivated by nuclear energy's ability to reduce human CO2 emissions, plugging the looming energy gap should be motivation enough. They present a possible two-stage nuclear renaissance for the United Kingdom in the graphic below (Grimes is at the Centre for Nuclear Engineering, Imperial College London, and Nuttall the Engineering Department, Cambridge University).

Steps to develop the first wave are already underway, allowing the United Kingdom to “replace nuclear with nuclear.” The second wave would allow nuclear energy to play a major role in electricity “decarbonization.” For most nations, the most immediate challenges are nuclear life extension and how best to renew existing nuclear generation infrastructure. Such steps do little to meet future need, but they can preserve diversity of fuel sources and technology in the electricity generation mix.

To realize the second phase of the nuclear renaissance, new reactor designs will be needed to take power plant design beyond the current Generation III plants. Among the new Generation IV plant designs are pebble bed reactors, the Toshiba 4S (the four S's in the name stand for super, safe, small, and simple), and the TerraPower TP-1 , a reactor that can run for decades by producing a nuclear reaction wave that breeds and burns its own fuel. Other possibilities include small modular reactors, a favorite of Secretary Chu's, such as the small light-water reactor from NuScale and the Hyperion Power Module.

The Hyperion design is interesting because they had been developing a revolutionary, inherently safe sealed small reactor. The Hydrogen Moderated Self-Regulating Nuclear Power Module (HPM), also referred to as the Compact Self-regulating Transportable Reactor (ComStar), is a new type of nuclear reactor originally developed at the Los Alamos National Laboratory. It uses uranium hydride as both its nuclear fuel and neutron moderator. However, in 2009, Hyperion Power Generation decided to use a different lead-cooled fast reactor design for its power module, based on uranium nitride, citing the long development and regulatory licensing process for the uranium hydride reactor design. Once again, government red tape at the DOE has stifled needed innovation. If the Obama administration wants to prove that they really have a future energy vision the President needs to clear out the ossified bureaucracy at the DOE.

The revised Hyperion Power Module design.

Because intermittent energy sources like wind and solar have by nature much lower capacity factors than baseload coal, gas, and nuclear, their maximum contribution to power generation is limited to around 20%. As Denmark and other European nations have discovered, without the steady baseload power of Scandinavian hydroelectric generators and French nuclear power plants, the wind just doesn't provide what the public demands—stable, reliable electricity.

The US Congress promised up to $18.5 billion in loan guarantees for nuclear construction, an amount that Energy Secretary Chu has pointed out would be enough to secure financing for only two projects at current prices. This might not be adequate to establish confidence in the new designs. Even so, signs of public acceptance are hopeful. Even a number of leading environmental organizations, such as the Environmental Defense Fund, have quietly or implicitly adopted a pro-nuclear position. Still, the neo-Luddites of Greenpeace, Friends of the Earth, Union of Concerned Scientists, and Physicians for Social Responsibility remain firmly opposed. Unsurprisingly, these drinkers of green cool-aid offer no workable solutions, just opposition.

In 2008, the US DOE reported that wind could, in principle, supply 20% of America's electricity by 2030. In an EnergyBiz interview, Spanish wind power giant Iberdrola's renewables executive Don Furman answered that projection succinctly: “Certainly not in the next 20 years.” The question that seldom gets asked is, what happens after we get to 20 percent? Hopefully, the nuclear renaissance will have rendered that question moot before an answer is needed.

Be safe, enjoy the interglacial and stay skeptical.

Candu Reactors

In 1977 the Canadian Candu reactor was put forward as a suitable system for New Zealand (being earthquake prone). The system was based on a low power density so that a bent fuel rod would not cause a significant hot spot and possible melt-down. My query is - is this technology still a possible nuclear power plant option?

CANDU reactors

The CANDU ("Canadian Deuterium Uranium") reactor was a very interesting design, a pressurized heavy-water power reactor designed in the late 1950s. It was designed to run on a variety of fuel types and to be inherently safe. Among the unique features is the ability to continuously refuel the reactor without shutting it down. For more on the safety features see the FAQ.

Evidently, the latest version is called the CANDU 6, and a number of units have been built in Canada, South Korea and China. The official site of the CANDU owners group can be found here. As far as I can tell, there is ongoing development of CANDU type reactors, particularly in India.


Thorium is the future, not Uranium

Not on its own

Quoting from the Wikipedia article on the thorium fuel cycle:

The thorium fuel cycle is a nuclear fuel cycle that uses the naturally abundant isotope of thorium, 232Th, as the fertile material which is transmuted into the fissile artificial uranium isotope 233U which is the nuclear fuel. However, unlike natural uranium, natural thorium contains only trace amounts of fissile material (such as 231Th) that are insufficient to initiate a nuclear chain reaction.

In short, you cannot build a reactor using thorium alone. I do agree that thorium can play a large part in the world's energy future, being about four times more abundant than uranium. Using thorium to augment uranium could yield more than 1,000 years of clean energy for the entire world. But don't dismiss the need or importance of uranium.

Thorium only remains unproven

You are undoubtedly referring to an Accelerator-Driven System (ADS). In such a system, a particle accelerator is used to provide a neutron source by shooting protons into a spallation target (eg. a blanket of lead). In turn, the neutrons collide with thorium atoms, converting thorium into fissile 233U. The uranium then fissions, providing (hopefully) a larger amount of energy than consumed by the accelerator. Nuclear physicist Carlo Rubbia was one of the first to propose such a subcritical reactor, which he called and “energy amplifier.”

The reason for all this complexity is that thorium on its own is not fissile. It must be converted into suitable fissile material by being exposed to a neutron source. Since the ADS design does not provide a sufficient mass of fissile material for it to maintain a fission chain reaction spontaneously—hence the designation as a subcritical reactor—it will only run when the accelerator beam is on. This makes the design fairly safe—cut power to the accelerator and the reactor shuts down. Unfortunately, while the ADS design has promise, it presents many challenges.

The design of a commercial system remains mostly theoretical. While lab tests have proven the concept of using a particle beam to start the thorium fuel cycle, the physics of scaling it up to the size of a commercial reactor are unproven and could be more complex. Then there's the way the particle beam interacts with the spallation target and the fuel in order to operate efficiently. Irradiated thorium fuel would also be highly radioactive, which could increase possible hazards and expense.

Any thorium reactor will have a high initial cost, but CERN stresses that a long-life reactor will be highly competitive compared to fossil and renewable energy fuels. CERN released a detailed report covering the financial viability of an ADS power plant and found it to be three times cheaper than coal and 4.8 times cheaper than natural gas. Such cost estimates have a strange way of never working out in real life.

None of this changes the fact that ADS is an unproven design. An ADS reactor would have to be designed, built and paid for from scratch, a prospect that presents enormous risk for potential investors, while there are plenty of existing conventional nuclear reactors that can be fairly inexpensively converted to mixed thorium fuel.

In short, there are simpler, proven ways of utilizing thorium. The following is from TEA's own brochure:

Thorium is a fertile fuel, meaning that it must first be converted into a fissile form before it can produce power...

...To convert the Thorium into a reactor fuel, it must be exposed to a neutron source. After absorbing a neutron from the reactor core, the Thorium is removed to a decay tank where it converts to Uranium 233, the primary fuel for the reactor.

The brochure even has a nice picture of a uranium fueled reactor into which thorium is to be inserted. They only show 233U, which is only created when thorium gets bombarded by high speed neutrons. Where do they come from? Why from the normal uranium fueled nuclear reaction that is needed to drive the conversion process. The tip-off is when they say that funding was cut so the thorium blanked was never added. In other words, what they had was a uranium fueled liquid salt reactor (and I don't mean 233U either).

In theory, it is possible to run a breeder on thorium alone once you have enough 233U to sustain the reaction. Estimates of “enough” are around 5.5 tons. Of course, to get that 233U you must have started with a neutron source. A nuclear accelerator can be used, which requires massive amounts of power from some where, but the source most typically is a 235U powered fission reaction. See the IAEA report PDF for general details.

Thorium looks like an interesting supplement to current fission technology. It is abundant and the fuel cycles being investigated pose minimal proliferation risks. Several large-scale projects are going on in Europe and Japan to further develop thorium ADS technology but currently, you can't fire up a commercial reactor starting with thorium alone. Speculating about future power sources is fun but, as we pointed out in The Energy Gap, plans for future energy production must be based on proven and available technology. Depending on an unproven technology to solve our future energy problems is like buying a lottery ticket as a retirement plan.

Fool Aid

i just wanted to say thank you for my morning chuckle. your fool aid picture was something special