Short Quiz - Suggested Answers

[johnkarls]

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Question 1

How big are nuclear-power reactors?

Answer 1

The reason for this question is that in March 2007 shortly after winning his Nobel prize, Al Gore testified before a U.S. Senate Committee that nuclear reactors “come in only one size – extra large.” It would appear that Al Gore was merely voicing the common misperception.

The first nuclear reactor built in the U.S. was for the Nautilus nuclear-powered submarine which was launched in 1954. All of our submarines since 1954 and all of our aircraft carriers built in the last 4 decades have been powered solely by on-board nuclear reactors.

These reactors, of course, are tiny compared to the typical land-based nuclear power reactors. The reason, of course, is that large reactors are more economical, but U.S. Naval submarines and aircraft carriers do not have the option of using larger reactors.

Incidentally, you might be amused to know that virtually all land-based nuclear power plants are staffed by retired U.S. Navy nuclear-power personnel.

Question 2

How much fuel is required for a nuclear-power reactor?

Answer 2

A 1,000 megawatt coal-fired electrical-generating plant requires 110 railroad cars of coal EVERY DAY.

A 1,000 megawatt nuclear-powered electrical-generating plant requires only ONE 18-wheel tractor-trailer truck delivering new fuel rods EVERY 18 MONTHS.

Question 3

How much power is produced by the nuclear fission of one uranium atom, compared to the power produced in burning (aka oxidizing) the carbon in a single fossil-fuel molecule such as comprises coal, oil, gas, etc.?

Answer 3

2 million times as much.

Question 4

How much greenhouse gas is produced by a nuclear electrical-generation plant? By a coal-fired electrical generation plant?

Answer 4

Nuclear – none.

Coal-fired – you don’t even want to think about it!!!

Question 5

How much electricity is generated in the U.S. by nuclear power? Coal-fired plants? Hydro? Other?

Answer 5

Per the U.S. Energy Information Agency, the sources for electricity generation in the U.S. in 2010 =

Coal – 56.1%
Nuclear – 17.3%
Natural Gas – 15.5%
Hydro – 9.4%
Other – 1.7%

Question 6

How much electricity is generated in France by nuclear power?

Answer 6

According to the International Energy Agency, 77.1% of France’s electricity was produced by nuclear-power plants in 2010. According to http://www.CIA.gov, this enabled France to export to other countries 11.0% of the electricity it produced.

Question 7

What do the U.S. Department of Energy statistics say about the economic viability of nuclear power?

Answer 7

Cost/kW for NEW PROJECTS – per Table 8.13 of DOE’s March 2009 NEMS EMM Report (which had been released annually each March, but appears to have been discontinued by the Obama Administration) =

$634 = Adv Comb Turbine
$670 = Conv Comb Turbine
$948 = Adv Gas/Oil Comb Cycle (CC)
$962 = Conv Gas/Oil Comb Cycle
$1,370 = Distributed Generation – Base
$1,645 = Distributed Generation – Peak
$1,711 = Geothermal
$1,890 = Adv CC with carbon sequestration
$1,923 = Wind Onshore
$2,058 = Scrubbed Coal New
$2,242 = Conventional Hydropower
$2,378 = Integrated Coal-Gasification Comb
$2,543 = MSW - Landfill Gas
----------------------------
$3,318 = Adv Nuclear
----------------------------
$3,496 = IGCC with carbon sequestration
$3,766 = Biomass
$3,851 = Wind Offshore
$5,021 = Solar Thermal
$5,360 = Fuel Cells
$6,038 = Photovoltaic

A few points to ponder =

1. Many of the power sources are supply limited – for example, it is difficult to build new dams for hydroelectric power.

2. If “dirty” sources (particularly greenhouse-gas generators) are eliminated from the list, nuclear would probably win the energy derby on the basis of cheapest source that can be taken to the scale required.

3. If we do nothing, either “dirty” coal (“dirty” no matter how much “scrubbed”) or natural gas obtained using the new technique of fracturing geological formations (natural gas also produces greenhouse gas) appear likely to win the energy derby. After all, we are the Saudi Arabia of coal and the Saudi Arabia of fractured-formation natural gas.

Question 8

Of the three well-publicized nuclear-power accidents in the 50-plus years of nuclear electrical-power generation, what was the problem at Three-Mile-Island in Pennsylvania in 1979?

Answer 8

Human error. If humans had not intervened, the accident probably would not have happened.

A relief valve stuck open, draining cooling water from the core. Despite a hundred blinking lights and wailing sirens, the operators decided that the reactor core was GETTING TOO MUCH WATER when it actually was NOT GETTING ENOUGH. Accordingly, they began draining water. The mistake wasn’t caught in time. One-third of the core melted.

Question 9

What was the problem at Chernobyl Ukraine in 1986?

Answer 9

(1) Soviet engineers were so over-confident, they did NOT build containment chambers around their reactors; and (2) graphite was substituted for some of the water as the coolant in order to speed the process, but this is dangerous because graphite creates a positive feedback loop and because graphite, since it is pure carbon, is flammable at high temperatures.

On 4/26/1986, two teams of operators were struggling with each other to use the plant for two contradictory purposes -- one team supplying power to the grid and the other team experimenting to determine whether the momentum in the turbines would be enough to power the cooling system during an accidental shutdown. During the tussle, the water in the cooling system stopped circulating causing the water to overheat and send a burst of steam through the turbines. This revved up the power, overheating the core even more. The fuel rods melted, dropping right into the remaining coolant, causing a steam explosion which ignited the graphite.

All this produced a plume of radioactive smoke and debris stretching 3,000 feet into the air since there was no containment chamber.

[Containment chambers are required elsewhere in the world constructed of steel and concrete and designed, at least in the U.S., to withstand a direct hit by an airliner.]

Question 10

What appear to have been the problems at Fukushima Daiichi?

Answer 10

First, it should be noted that the earthquake that caused the tsunami at Fukushima Daiichi was 9.0 on the Richter scale, which was far more powerful than any previous earthquake in Japan.

Indeed, it was far more powerful than any earthquake in the United States since the U.S. Government Geological Service began keeping records in 1769 (which, for nit-pickers, was before the U.S. Government became the U.S. Government) = 2.63 times more powerful than California’s Great Earthquake of 1906, 16.99 times more powerful than the second most powerful earthquake in the U.S., and 34.48 times more powerful than the third most powerful earthquake in the U.S.

As a second preliminary matter, the media is almost invariably guilty of alarming the public with the use of the term “melt down” which the public generally assumes means the release of radiation -- which might or might not be true.

In simple terms, the fuel rods in the reactor core are located in a containment chamber constructed of steel and concrete and designed, at least in the U.S., to withstand a direct hit by an airliner.

If the integrity of the containment chamber is NOT breached, then any radiation from the fuel rods, no matter how badly they melt, can only become a threat to the outside world if (1) gases in the containment chamber are vented, or (2) water in the containment chamber circulates through pipes outside the chamber and leaks from the pipes.

From media reports, several, if not all, of the six reactors at Fukushima Daiichi experienced partial or total “melt downs” of their fuel rods because the plant design included electrical pumps for circulating the water for cooling the fuel rods and (1) the earthquake and/or tsunami knocked out the region’s electrical grid, (2) the tsunami flooded the basement(s) where Fukushima Daiichi’s back-up diesel generators were located, and (3) the tsunami washed away the diesel fuel tanks which were located on ground level.

Also from media reports: (1) shortly after the earthquake/tsunami, there was limited venting from some of the containment chambers to insure that the build-up in pressure did not itself burst any of the containment chambers, and (2) water from the containment chambers did leak, apparently from pipes outside the containment chambers.

Question 11

Do thorium-powered nuclear plants need containment chambers such as those at uranium-powered commercial nuclear plants?

(NB: Nuclear-powered American submarines and aircraft carriers do not have containment chambers, nor did the Soviet nuclear plant at Chernobyl.)

Answer 11

No. Thorium-powered nuclear plants do not operate at high temperatures or pressures, so there is virtually no risk of a “melt down” that would need to be contained.

Question 12

Do thorium-powered nuclear plants need elaborate water-cooling systems?

Answer 12

No, because thorium-powered nuclear plants do not operate at high temperatures.

Question 13

Why do spent uranium fuel rods pose a problem for U.S. uranium-powered nuclear plants? Why do the French NOT have spent fuel rods?

Answer 13

Uranium fuel rods become enriched as they are used and “re-processed.” Long ago, the U.S. made the decision that it did not want fuel rods to become so enriched that they reached “weapons grade.”

France, on the other hand, long ago decided that it was no more trouble to provide the same level of security for their nuclear electrical-generation plants than they routinely provide for their nuclear weapons. Accordingly, their fuel rods are “re-processed” and there is no significant “spent fuel rod” problem in France.

Question 14

Do thorium-powered nuclear plants have waste problems?

Answer 14

They do have waste, but it is infinitesimal compared with uranium-powered nuclear plants.

Question 15

Since thorium-powered nuclear plants are so much safer to operate, since they do not require containment chambers, since they do not require elaborate water-cooling systems, since they do not have significant nuclear-waste problems, since thorium is so plentiful/cheap, and since construction and operating costs of thorium-powered nuclear plants would be so much less than uranium-powered nuclear plants -- why did President Nixon order the nation’s nuclear-science laboratory at Oak Ridge to halt development of thorium-based nuclear power?

Answer 15

Because President Nixon thought it would save costs to have the nuclear electrical-generation industry “piggy back” on the nation’s uranium-based weapons industry.

Question 16

In addition to comprising a solution to global warming, would thorium-powered nuclear reactors eliminate our gaping international balance-of-payments deficit, and eliminate the political reliance of the U.S. and its allies on Middle East oil producers?

Answer 16

Of course.

Question 17

Are other countries as well as foreign-based multi-national companies racing to develop and implement thorium-based nuclear technology, leaving the U.S. in the dust?

Answer 17

The Huffington Post review of liquid-floride thorium reactors (posted on http://www.ReadingLiberally-SaltLake.org) reports that China, France, Japan, Russia, the Netherlands, Canada, the Czech Republic and several European-based multi-national companies are racing to develop and implement thorium-based nuclear technology.

The Huffington Post review finishes with a flourish = “The only significant U.S. research is on molten salt reactors, with no emphasis on thorium. The U.S. may end up buying LFTR’s from China. Perhaps WalMart will sell them cheap.”