Ben Bova: Nuclear power
People are scared of nuclear power plants, and I can't blame them. Disasters such as Chernobyl and Fukushima are certainly frightening.
Engineers insist that they can build much safer nuclear power plants, and protect them against natural disasters such as the earthquake and tsunami that smashed up the Fukushima plants in Japan.
Of course, it would be better if nuclear power plants were sited in locations that are not prone to earthquakes and tsunamis. But even so, the cold facts are that nuclear power plants are far safer than power plants using fossil fuels.
Accidents in coal mines, oil rigs, and natural gas pipelines have taken far more lives over the years than nuclear power plant accidents.
Moreover, fossil fuel power plants pollute the air we breathe and the water we drink. Their emissions of greenhouse gases are a major factor in the warming of our global climate.
Even so, there is a lingering problem with nuclear power. What to do with the radioactive wastes?
For more than half a century radioactive materials have been piling up, the waste products of nuclear power plants. There are nearly 500,000 cubic yards of radioactive wastes stashed around the U.S., most of it from military weapons programs, not civilian power plants.
While that amount of material is smaller than a single average-sized city garbage dump, it's worrisome — because some of those wastes will remain dangerously radioactive for thousands of years.
Getting rid of the waste material safely has been a political hot potato for decades. Nobody wants a radioactive garbage dump in his back yard. The federal government spent billions of dollars over a couple of decades preparing an underground facility at Yucca Flats, Nevada, to store the wastes, but political pressures made President Barack Obama scrap the plan.
So the wastes sit mainly at the power plants where they were produced, a potential threat to the area, and a tempting target for terrorists.
But what if the wastes could be somehow transformed into inert, non-radioactive material? What if we could do what the medieval alchemists wanted to achieve – in reverse? Instead of transforming lead into gold, suppose we could transform radioactive uranium, strontium, plutonium, thorium, et al. into lead or some other inert elements?
Scientists in Britain believe they can accomplish such a seemingly magical trick, and generate electrical power in the bargain.
They envision using a particle accelerator – the kind of "atom smasher" physicists use to study the inner structure of fundamental particles – to bombard radioactive materials with neutrons and turn them into safe, non-radioactive elements.
The accelerator system could be designed to generate electrical power while it's deactivating the radioactive wastes. A system that needs 20 megawatts of power to operate could generate 600 megawatts, they believe.
Instead of storing the wastes for centuries or millennia, convert them to harmless elements and generate copious amounts of electrical power while you're at it!
There are plenty of technical problems to be dealt with before such a facility becomes a reality, but scientists and engineers can undoubtedly solve them, in time.
It's the political problems that worry me. The existing buildup of radioactive wastes is a political problem, more than a technical one. The wastes can be stored safely, but many people don't believe that.
Because they fear anything and everything connected with radioactivity, they have created a political logjam that sees the problem grow worse with each passing year.
People don't want truckloads of radioactive waste traveling through their neighborhoods, even if the waste is on its way to be deactivated. This short-sighted NIMBY attitude is counterproductive. It has already cost us billions of tax dollars for the abandoned Yucca Flats storage facility, with nothing to show for it.
I believe nuclear energy can be an important part of our future energy picture. Despite Chernobyl and Fukushima, I believe that we can build safe, reliable nuclear power plants and get rid of their radioactive wastes while generating still more electrical power from them.
The next step is to build a demonstration system to prove that the wastes can be safely deactivated. That is underway now, in Britain.
Details about the British work are in New Scientist magazine's May 26 issue.
Ben Bova is from Naples. His latest technothriller, "Power Play,'' deals with new energy technology. His web site is www.benbova.com.
One year on from Fukashima, the nuclear renaissance well underway
Drilling for uranium in Namibia - Deep Yellow (Supplied)
The African country of Namibia has emerged as a powerhouse of uranium mining, and Australian companies have a major presence there.
The World Nuclear Association says there's over 400 reactors operating around the world, with another 60 under construction in 14 different counties.
Natural resources analysts GBI Research has released a report saying uranium mining is set to soar due to the rising demand for nuclear power,
Western Australia will have its first uranium mine within a year, and both the Northern Territory and South Australia have long histories of uranium mining.
Greg Cochrane is the CEO of Perth Company Deep Yellow, which has a uranium project in Namibia called Omahola
Mr Cochrane says despite the claims of some, the meltdown of the Fukashima nuclear power plant in Japan hasn't dampened demand for nuclear energy at all.
In fact, Japan has just announced it's reopening two damaged plants very soon.
"There is a perhaps a fringe that might make those claims, but mostly that fringe is in Australia, certainly not in the rest of the rational world.
"What we see is the Japanese recommissioning, the Chinese are back to where they were with their construction and build program, as are the Koreans.
"But there are new areas of growth, particularly in the Middle East, where there are are slated 20 reactors to be built in the next 10 years, that weren't even there prior to Fukashima."
See another Uranium Miner....??? in Africa, Namibia..??
Perth company Deep Yellow exploring for uranium in Namibia, Africa | Photographer: | Supplied
Cowboy State is in the nuclear age
RYAN JAMES, Rock Springs Rocket-Miner
Updated 08:16 a.m., Sunday, June 24, 2012
ROCK SPRINGS, Wyo. (AP) — The Great Plains region of the U.S. Midwest is often referred to as the Corn Belt, comprising much of the nation's agricultural production.
The region from the Midwest to the Northeast is the Rust Belt, with industrial manufacturing traditionally dominating the local economies.
Wyoming is the powerhouse. Almost every resource that fuels cars, planes, trains and power plants in the United States is extracted in the Cowboy State, including oil, natural gas, coal, sodium bicarbonate and uranium.
The state's southwest corner is rich in all five and produces almost all of the world's trona, or sodium bicarbonate, which is refined into soda ash.
While Sweetwater County's economy is driven by oil, gas and trona production, a planned uranium mine in the Lost Creek area north of Wamsutter is expected to increase domestic production between 25 and 50 percent by 2014.
Total uranium production in the United States for nuclear power generation is currently about 4 million pounds per year.
Ur-Energy, which has acquired most of the necessary licenses and permits for the project, anticipates an annual output of 1 million to 2 million pounds of refined yellowcake uranium powder.
Production is slated to begin spring 2013 and increase to full capacity by 2014.
Uranium has been mined in the Great Divide Basin, which cuts through south-central Wyoming up to its northwest corner, for more than 40 years.
One of Ur-Energy's co-founders was a uranium prospector and geologist in the 1960s and '70s who long suspected the Lost Creek area was rich with the element. It wasn't until 2005, however, that the company was established and the permitting process began.
Steve Hatten, the vice president of operations, said the company would fill 58 positions, ideally from surrounding communities.
"I'd like to see folks from Bairoil, Wamsutter, Jeffrey City and Rawlins get involved. They're pretty close, and we really hope to impact all those communities in a very positive way," Hatten tells the Rock Springs Rocket-Miner (http://bit.ly/PngwDS). "We have had nothing but positive comments from all the communities."
About $4 million will be paid each year for salaries, with positions including field construction, engineering, geology, managerial, accounting and maintenance.
Uranium mining is different than the common conception of tunnels, thick with dust as pickaxes clank in the dimly lit gloom.
Uranium is a thin coating on the grains of sandstone formations 70 to 80 feet thick and about 450 feet below the surface at the Lost Creek property, Hatten said. About 15 feet of uranium will be extracted from the formations.
The process begins at an injection well, where groundwater is extracted, infused with sodium bicarbonate, carbon dioxide and oxygen, and re-injected into the rock formation.
A PVC pipe encased in concrete goes down to the 450-foot production horizon, where the mining solution is flushed through the formation.
The uranium-laden solution is then pumped back to the surface through a production well about 70 feet away.
The Lost Creek operation will process 6,000 gallons per minute at full capacity.
Both the production and injection wells are connected to the processing plant via pipes 6 feet underground to prevent water from freezing in the winter.
The company anticipates the operation will be productive for about 10 years.
Because of the dangers of radioactivity and the process of flushing uranium through the subsurface, mining companies must navigate a maze of permits and regulations and steer clear of any drinking water sources.
Uranium produces the highly radioactive element radium as it decays, so uranium-bearing formations contain higher radium concentrations.
Water in uranium-bearing formations is generally not suitable for drinking before or after mining.
"The water quality is generally bad. It's high in radium, uranium and other contaminants," Hatten said.
Southwest Wyoming adding more uranium mining to its already rich minerals industry
ROCK SPRINGS, Wyo. —
The Great Plains region of the U.S. Midwest is often referred to as the Corn Belt, comprising much of the nation's agricultural production.
The region from the Midwest to the Northeast is the Rust Belt, with industrial manufacturing traditionally dominating the local economies.
Wyoming is the powerhouse. Almost every resource that fuels cars, planes, trains and power plants in the United States is extracted in the Cowboy State, including oil, natural gas, coal, sodium bicarbonate and uranium.
The state's southwest corner is rich in all five and produces almost all of the world's trona, or sodium bicarbonate, which is refined into soda ash.
While Sweetwater County's economy is driven by oil, gas and trona production, a planned uranium mine in the Lost Creek area north of Wamsutter is expected to increase domestic production between 25 and 50 percent by 2014.
Total uranium production in the United States for nuclear power generation is currently about 4 million pounds per year.
Ur-Energy, which has acquired most of the necessary licenses and permits for the project, anticipates an annual output of 1 million to 2 million pounds of refined yellowcake uranium powder.
Production is slated to begin spring 2013 and increase to full capacity by 2014.
Uranium has been mined in the Great Divide Basin, which cuts through south-central Wyoming up to its northwest corner, for more than 40 years.
One of Ur-Energy's co-founders was a uranium prospector and geologist in the 1960s and '70s who long suspected the Lost Creek area was rich with the element. It wasn't until 2005, however, that the company was established and the permitting process began.
Steve Hatten, the vice president of operations, said the company would fill 58 positions, ideally from surrounding communities.
"I'd like to see folks from Bairoil, Wamsutter, Jeffrey City and Rawlins get involved. They're pretty close, and we really hope to impact all those communities in a very positive way," Hatten tells the Rock Springs Rocket-Miner (http://bit.ly/PngwDS). "We have had nothing but positive comments from all the communities."
About $4 million will be paid each year for salaries, with positions including field construction, engineering, geology, managerial, accounting and maintenance.
Uranium mining is different than the common conception of tunnels, thick with dust as pickaxes clank in the dimly lit gloom.
Uranium is a thin coating on the grains of sandstone formations 70 to 80 feet thick and about 450 feet below the surface at the Lost Creek property, Hatten said. About 15 feet of uranium will be extracted from the formations.
The process begins at an injection well, where groundwater is extracted, infused with sodium bicarbonate, carbon dioxide and oxygen, and re-injected into the rock formation.
A PVC pipe encased in concrete goes down to the 450-foot production horizon, where the mining solution is flushed through the formation.
The uranium-laden solution is then pumped back to the surface through a production well about 70 feet away.
The Lost Creek operation will process 6,000 gallons per minute at full capacity.
Both the production and injection wells are connected to the processing plant via pipes 6 feet underground to prevent water from freezing in the winter.
The company anticipates the operation will be productive for about 10 years.
Because of the dangers of radioactivity and the process of flushing uranium through the subsurface, mining companies must navigate a maze of permits and regulations and steer clear of any drinking water sources.
Uranium produces the highly radioactive element radium as it decays, so uranium-bearing formations contain higher radium concentrations.
Water in uranium-bearing formations is generally not suitable for drinking before or after mining.
"The water quality is generally bad. It's high in radium, uranium and other contaminants," Hatten said.
Ur-Energy has received eight of the nine necessary regulatory approvals for Lost Creek, including a Wyoming Department of Environmental Quality permit to mine, Nuclear Regulatory Commission source and byproduct materials license, DEQ air quality permit, Wyoming Game and Fish Department wildlife management plan and Sweetwater County development plan.
The company is awaiting final approval of the plan of operations by the Bureau of Land Management, which CEO Wayne Heili said he hopes will be granted before August.
Every material that could be removed with the uranium must be identified in an environmental impact statement, Hatten said.
The company will also be required to monitor water around the area of interest to ensure no contaminants seep beyond this boundary.
The permitting process culminates with the environmental impact statement, which includes surface, subsurface and groundwater impacts; operation and processing methods; and reclamation methods once the uranium is no longer economically feasible to extract.
Because the process doesn't slurry the sand below, it doesn't create physical caverns of displaced material, Hatten said.
"When we talk about subsurface effects, we're not talking about physical effects. We're talking about chemical effects and mobilizing constituents in the groundwater," Hatten said. "Unlike a conventional mine, we don't take away the surface to get to the subsurface. It is literally inconsequential to the total volume . (Uranium) is truly a mild coating on the sand grains. You will see no subsidence and no effects to the formation."
Uranium mining companies must submit a multimillion dollar bond to the DEQ, which is returned upon completion of a successful reclamation. If a company folds or does not adequately reclaim an area, the bond is forfeited and used to fund the cleanup.
Once mining is completed, the EPA issues an aquifer exemption permit that limits use of the area to mining in general.
Wastewater can be disposed of several different ways, including extraction, treatment and re-injection. Hatten said Ur-Energy plans to inject the waste in deep disposal wells permitted and approved by the state. It will be treated using ion exchange, reverse osmosis and simple filtration.
The company must remove well bore piping, connector pipes and roads. Under its reclamation plan, the well bores will be sealed with concrete, the surface reseeded and the processing plant dismantled and removed.
The life cycle for each 30- to 40-acre mine unit from preproduction drilling and construction to final reclamation is three to four years, Hatten said. About 600 to 700 wells will be drilled on each unit.
Nuclear power plants generate about 20 percent of the electricity used in the United States.
"We really consider nuclear and hydroelectric power as the base load power in the U.S. because those don't really turn off and on, where coal and natural gas become a little bit more flexible," Hatten said.
___
Information from: Rock Springs (Wyo.) Rocket-Miner,http://www.rocketminer.com
Sardul Minhas: A future for nuclear power
Fukushima doesn't need to spell the end of safely operated nuclear power plants.
Public attitudes toward nuclear energy hardened following the accident at Three Mile Island in 1979 and the Chernobyl disaster in 1986.
The accident at the Fukushima Daiichi plant in March 2011 would have been expected to have a similar effect. However, a survey conducted by Bisconti Research, and sponsored by Nuclear Energy Institute, six months after the tsunami overwhelmed the Fukushima plant determined that large majorities of Americans continued to have favorable opinions about nuclear energy and new power plants. Sixty-two percent of respondents favored nuclear energy, a drop of 9 percent from a similar survey conducted a month before Fukushima.
MCT ILLUSTRATION
Considering the scale of the disaster, this was a minor decline.
The American public appreciates the need for intensive risk analysis of nuclear plants and the incorporation of engineering safeguards against natural and runaway disasters. Taller and much-sturdier sea walls would have mitigated against the disastrous loss of cooling in the Fukushima reactors, for example. Perhaps another mitigating step would be to not permit nuclear power plants in areas most prone to intense earthquakes and tsunamis. It is an apt challenge for nuclear regulatory agencies.
Nuclear power is a critical tool in our arsenal to reduce greenhouse gas emissions and should stay in the broad mix of responses to climate change. It continues to be cost-competitive with electricity from power plants burning fossil fuels, such as coal and natural gas.
However, long-term generation of nuclear power is contingent on effectively addressing the issue of the radioactive waste.
The normal uranium fuel cycle starts with the enriched fissile uranium isotope U235. Fission of this isotope produces a highly toxic and radioactive blend consisting of plutonium and byproducts, which slow the chain reaction, forcing replacement of fuel rods every one to two years.
Perhaps the most straightforward option would be to store the spent fuel rods at power plant sites till underground repositories can be readied. However, Nevada's Yucca Mountain nuclear waste repository, the one feasible option in the United States, was defunded by Congress in 2010. It is unlikely to move forward.
Another option is to reprocess the spent fuel using an update of the 65-year-old Purex process developed in the Manhattan Project, recovering plutonium and uranium (the U238 as well as the unconverted U235). The waste from reprocessing is less radioactive; it is sealed in caskets and stored.
The United States reprocessed spent fuels for several decades to recover plutonium for use in nuclear weapons, until President Jimmy Carter banned reprocessing in 1977 as part of a nuclear-weapons nonproliferation drive.
France's Areva Group has reprocessed spent fuel rods at La Hague since the early 1960s without any safety or environmental incident. Areva typically achieves a reduction in the mass of the final vitrification canisters by a factor of 10, compared with unprocessed fuel.
There is a third option: switching to a thorium fuel cycle. Thorium can't sustain a chain reaction on its own, but it absorbs neutrons to form U233 – another fissile isotope of uranium that will. These neutrons are supplied by uranium enriched with the U235 isotope.
A thorium-fueled reactor produces about one-third the waste of a similar uranium-fueled reactor. If combined with waste reprocessing, the overall reduction in the mass of the final canister waste – relative to unprocessed waste from a uranium fueled reactor – is by a factor of 20 to 40.
Thorium is three to four times more abundant in nature than uranium, and much of it is easily accessible. The United States has the second-largest extractable reserves of thorium, 15 percent of the global total. More importantly, thorium contains about 40 times as much available energy as naturally mined uranium. This is so because natural uranium contains only 0.7 percent of the fissionable U235 isotope, while mined thorium is entirely usable for energy production.
For each unit of power generation, the thorium fuel cycle has three advantages over the conventional uranium fuel cycle: less fuel cost, less waste and less plutonium formation in the reactor. That final factor helps in the weapons non-proliferation effort if the waste is reprocessed and the plutonium recovered.
Several early reactors using the thorium fuel cycle were operated in the United States in the 1960s and 70s. However, they used very highly enriched uranium as the chain initiator, which is no longer feasible. There was also an early preference for the uranium fuel cycle because it allowed for the production of plutonium for use in nuclear weapons. Thorium fell out of favor as the nuclear industry standardized around uranium in the 1970s.
The thorium fuel cycle has been resuscitated in the past 15 years. Many reactor designs have been tested, including the traditional fuel bundle cores, moving bed, as well as molten-salt reactors. The technology needs a lot of catch-up development work.
Uranium was preferred by the US over Thorium, because as a byproduct, we could get Plutonium for bombs. Now that we have enough Plutonium to destroy the world many times over, it is no longer an issue. Had we gone down a Thorium path for commercial reactors, there would not be the same proliferation problem, because Plutonium is not a byproduct.
In a meltdown, Uranium reactors require working plumbing and electric power for months, to control and cool a Uranium reactor. Thorium is safer, because it has passive safety, where in a melt down, the liquid thorium spreads out in the bottom of the vessel, the mass goes non critical, and it cools by itself.
The waste from Uranium reactors is going to need technicians to look after it for 100,000 years, where as Thorium is less dangerous and toxic, and only needs to be looked after for 400 years.
Thorium is abundant in India and China, and both are switching to Thorium. That is the future.
John T. Robinson · Missing Cog at Broken Gear
I like this Kirk Sorensen (Flibe Energy co-founder) video explaining LFTRs because it's short enough (10 min.) that somebody might actually watch it, and it covers most of the key points. Shame we (i.e. the US) will probably end up buying them from China. The US also has plenty of thorium of course (in fact we have stockpiles of it already).
http://www.youtube.com/
http://www.youtube.com/
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