Thanks to Fukushima the Germans are Returning to Coal

Posted by PITHOCRATES - February 15th, 2014

Week in Review

Germany was going green.  Between renewables and nuclear power they were really shrinking their carbon footprint.  But then along came Fukushima.  And the melting of the core in a nuclear power plant.  Sending shockwaves throughout the world.  Causing the Germans to shut down their nuclear reactors.  Of course, that created an energy shortage in Germany.  And how did they fill it?  By building more new wind farms?  No (see Germany Is Relocating Entire Towns To Dig Up More Sweet, Sweet Coal by Kelsey Campbell-Dollaghan posted 2/14/2014 on Gizmodo).

Most of us think of Germany as one of the most energy-progressive countries in the world. But in recent years, it’s also increased its dependence on a form of energy that’s anything but clean: coal. And it’s demolishing or relocating entire towns to get at it.

While Germany has some of the largest brown coal deposits on Earth, a valuable chunk of it resides underneath towns that date back to the Middle Ages. Most of these are located in the old East Germany, and in the 1930s and 40s, dozens of them were destroyed to make way for mining. The practice ended when Germany established its clear energy initiatives. But now, dirty brown coal reemerging as a cheaper option than clean energy. And the cities are in the way again.

Sunshine and wind are free.  They may be unreliable but they are free.  But to capture that energy requires an enormous and costly infrastructure.  That could still fail to produce the electric power they need when the wind doesn’t blow.  Leaving them but one option to replace those efficient nuclear power plants.  Efficient coal-fired power plants.  Which is the only option they have.  Because renewables can never provide baseload power.  The power that is always there and can be relied upon.  Like nuclear power plants.  And those big, beautiful coal-fired power plants.  Rain or shine. Night or day.  Wind or calm.  Coal is always there for us.

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After Fukushima Meltdown shuts down Nuclear Power Industry Japan turns to Solar Power

Posted by PITHOCRATES - November 10th, 2013

Week in Review

Japan shows how easy it is to go green after the Fukushima Nuclear Power Plant meltdown.  Nuclear power is unsafe.  Coal-fired power plants are too dirty.  So what to do?  Why, go solar, of course (see Kyocera launches 70-megawatt solar plant, largest in Japan by Tim Hornyak posted 11/8/2013 on CNET).

Smartphone maker Kyocera recently launched the Kagoshima Nanatsujima Mega Solar Power Plant, a 70-megawatt facility that can generate enough electricity to power about 22,000 homes.

The move comes as Japan struggles with energy sources as nuclear power plants were shut down after meltdowns hit Tokyo Electric Power Co.’s Fukushima plant in 2011.

Set on Kagoshima Bay, the sprawling Nanatsujima plant commands sweeping views of Sakurajima, an active stratovolcano that soars to 3,665 feet.

It has 290,000 solar panels and takes up about 314 acres, roughly three times the total area of Vatican City.

Wow, 70 megawatts.  Sounds big, doesn’t it?  With 290,000 solar panels on 314 acres.  An installed capacity of 0.22 megawatts per acre.  It must have cost a fortune to build.  And they built it on a bay.  At sea level.  In the shadow of an active volcano.  It would be a shame if that volcano erupts and covers those solar panels in a layer of ash.  Or if another typhoon hits Japan.  An earthquake.  Or a storm surge.  For if any of these things happen those 22,000 homes will lose their electric power.

So how does this compare to the Fukushima Daiichi Nuclear Power Plant?  Well, that plant sits on 860 acres.  And has an installed capacity of 4700 megawatts.  Or the installed capacity of 67 Kagoshima Nanatsujima Mega Solar Power Plants.  And an installed capacity of 5.47 megawatts per acre.  Which is perhaps why they built this on the bay.  Because it is such an inefficient use of real estate in a nation that has one of the highest population densities that they put it on the water.  To save the land for something that has value. 

We used the term ‘installed capacity’ for a reason.  That reason being the capacity factor.  Which is the actual amount of power produced over a given amount of time divided by the maximum amount of power that could have been produced (i.e., the installed capacity).  Nuclear plants can produce power day or night.  Covered in volcanic ash or not.  On a sunny day or when it’s pouring rain.  Which is why a nuclear power plant has a much higher capacity factor (about 90%) than a solar plant (about 15%).  So the actual power people consume from the Kagoshima Nanatsujima Mega Solar Power Plant will be far less than its 70 megawatts of installed capacity.

So in other words, solar power is not a replacement for nuclear power.  Or any other baseload power such as coal-fired power plants.  Power demand will far exceed power supply.  Leading to higher costs as they try to ration electric power.  And a lot of power outages.  Some longer than others.  Especially when powerful typhoons and/or storm surges blow in.  As they often do in the Pacific Ocean.

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Japan Turning to Wind Power after the Fukushima Nuclear Power Accident in 2012

Posted by PITHOCRATES - January 19th, 2013

Week in Review

Japan suffered a close call in 2012.  The nuclear power plant at Fukushima survived the massive earthquake.  But the resulting tsunami led to electric problems in the backup power systems.  Which led to the core meltdown.  Something that never happened before.  And is not likely to happen again.  Because they saw what that tsunami did.  And now can prepare these plants to handle future tsunamis.  Still, the Japanese are turning their back on nuclear power.  After it served them so well all these many years (see Japan to build world’s largest offshore wind farm by Rob Gilhooly posted 1/16/2013 on New Scientist).

By 2020, the plan is to build a total of 143 wind turbines on platforms 16 kilometres off the coast of Fukushima, home to the stricken Daiichi nuclear reactor that hit the headlines in March 2011 when it was damaged by an earthquake and tsunami.

The wind farm, which will generate 1 gigawatt of power once completed, is part of a national plan to increase renewable energy resources following the post-tsunami shutdown of the nation’s 54 nuclear reactors. Only two have since come back online…

The first stage of the Fukushima project will be the construction of a 2-megawatt turbine, a substation and undersea cable installation. The turbine will stand 200 metres high. If successful, further turbines will be built subject to the availability of funding.

To get around the cost of anchoring the turbines to the sea bed, they will be built on buoyant steel frames which will be stabilised with ballast and anchored to the 200-metre-deep continental shelf that surrounds the Japanese coast via mooring lines…

Another contentious issue is the facility’s impact on the fishing industry, which has already been rocked by the nuclear accident. Ishihara insists it is possible to turn the farm into a “marine pasture” that would attract fish.

The earthquake didn’t hurt the Daiichi nuclear reactor.  It was the tsunami.  Which flooded the electrical gear in the basement that powered the cooling pumps.  That same tidal wave that swept whole buildings out to sea.  Which it will probably do the same to those buoyant steel frames.  Which means instead of replacing downed power lines after another tsunami they will be replacing windmills.  Making the resulting power outage longer.  And more costly.

The wind farm will not generate 1 gigawatt.  It may have the potential to generate 1 gigawatt.  But that will be only when the winds cooperate.  They have to blow hard enough to spin the windmills fast enough to produce electric power.  But not too fast that they damage the windmills.  Which typically lock down in high winds.  Providing a narrow band of winds for power generation.

Buoyant windmills and underwater power cabling in fishing waters?  Sure, that shouldn’t be a problem.  What are the odds that a boat will run into a windmill?  Or snag an underwater power cable?  The odds of that happening are probably greater than another Fukushima-like accident.  And yet they’re shutting down their nuclear power.  To use floating windmills.

Incidentally, 143 windmills at 2 megawatt each only comes to 286 megawatts.  Not 1 gigawatt.  No, to get 1 gigawatt you’ll need 500 windmills.  Three and half times more than the 143 they’re planning to build.  If the one they start with works.  And they have the money for more windmills after they install the first one.

India has more wind and solar power than anyone else.  Yet they’re adding nuclear capacity because their wind and solar just can’t meet their power needs.  The Japanese should probably reconsider their position on nuclear power.  For even though wind power is green power and it will provide a lot of jobs it will result in massive debt.  And unreliable power.  That money would probably be better spent making improvements to their nuclear power.  Such as getting electric gear out of basements.  And providing a more failsafe power source for their cooling pumps.  For their nuclear plants can survive earthquakes.  And with these improvements they’ll be able to survive a tsunami.  All while providing reliable electric power.  Something windmills just can’t do.

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Electricity, Heat Engine, Superheated Dry Steam, Coal-Fired Power Plant, Geothermal Power Plant and Waste-to-Energy Plant

Posted by PITHOCRATES - November 7th, 2012

Technology 101

(Originally published August 1, 2012)

Geothermal Power Plants and Waste-to-Energy Plants each produce less than Half of 1% of our Electricity

We produce the majority of our electricity with heat engines.  Where we boil water into steam to spin a turbine.  Or use the expanding gases of combustion to spin a turbine.  The primary heat engines we use are coal-fired power plants, natural gas-power plants and nuclear power plants.  The next big source of electricity generation is hydroelectric.  A renewable energy source.  In 2011 it produced less than 8% of our electricity.  These sources combined produce in excess of 95% of all electricity.  While renewable energy sources (other than hydroelectric) make up a very small percentage of the total.  Wind power comes in under 3%.  And solar comes in at less than 0.2% of the total.  So we are a very long way from abandoning coal, natural gas and nuclear power.

Two other renewable energy sources appear to hold promise.  Two heat engines.  One powered by geothermal energy in the earth.  The other by burning our garbage.  In a waste-to-energy plant.  These appear attractive.  Geothermal power appears to be as clean as it gets.  For this heat isn’t man-made.  It’s planet-made.  And it’s just there for the taking.  But the taking of it gets a little complicated.  As is burning our trash.  Not to mention the fact that few people want trash incinerators in their neighborhoods.  For these reasons they each provide a very small percentage of the total electric power we produce.  Both coming in at less than half of 1%.

So why steam?  Why is it that we make so much of our electrical power by boiling water?  Because of the different states of matter.  Matter can be a solid, liquid or a gas.  And generally passes from one state to another in that order.  Although there are exceptions.  Such as dry ice that skips the liquid phase.  It sublimates from a solid directly into a gas.  And goes from a gas to a solid by deposition.  Water, though, follows the general rule.  Ice melts into water at 32 degrees Fahrenheit (or 0 degrees Celsius).  Or water freezes into ice at the same temperature.  Water vaporizes into steam at 212 degrees Fahrenheit (or 100 degrees Celsius).  Or steam condenses into water at the same temperature.  These changes in the state of matter are easy to produce.  At temperatures that we can easily attain.  Water is readily available to vaporize into steam.  It’s safe and easy to handle.  Making it the liquid of choice in a heat engine.

Today’s Coal-Fired Power Plant pulverizes Coal into a Dust and Blows it into the Firebox

A given amount of water will increase about 1600 times in volume when converted to steam.  It’s this expansion that we put to work.  It’s what pushed pistons in steam engines.  It’s what drove steam locomotives.  And it’s what spins the turbines in our power plants.  The plumes of steam you see is not steam, though.  What you see is water droplets in the steam.  Steam itself is an invisible gas.  And the hotter and drier (no water) it is the better.  For water droplets in steam will pit and wear the blades on a steam turbine.  Which is why the firebox of a coal-fired plant reaches temperatures up to 3,000 degrees Fahrenheit (about 1,650 degrees Celsius).  To superheat the steam.  And to use this heat elsewhere in the power plant such as preheating water entering the boiler.  So it takes less energy to vaporize it.

To get a fire that hot isn’t easy.  And you don’t get it by shoveling coal into the fire box.  Today’s coal-fired power plant pulverizes coal into a dust and blows it into the firebox.  Because small particles can burn easier and more completely than large chunks of coal.  As one fan blows in fuel another blows in air.  To help the fire burn hot.  The better and finer the fuel the better it burns.  The better the fuel burns the hotter the fire.  And the drier the steam it makes.  Which can spin a turbine with a minimum of wear.

In a geothermal power plant we pipe steam out of the ground to spin a turbine.  If it’s hot enough.  Unfortunately, there aren’t a lot of geothermal wells that produce superheated dry steam.  Which limits how many of these plants we can build.  And the steam that the planet produces is not as clean as what man produces.  Steam out of the earth can contain a lot of contaminants.  Requiring additional equipment to process these contaminants out.  We can use cooler geothermal wells that produce wet steam but they require additional equipment to remove the water from the steam.  The earth may produce heat reliably but not water.  When we pipe this steam away the wells can run dry.  So these plants require condensers to condense the used steam back into water so we can pump it back to the well.  A typical plant may have several wells piped to a common plant.  Requiring a lot of piping both for steam and condensate.  You put all this together and a geothermal plant is an expensive plant.  And it is a plant that we can build in few places.  Which explains why geothermal power makes less than half of 1% of our electricity.

We generate approximately 87% of our Electricity from Coal, Natural Gas and Nuclear Power

So these are some the problems with geothermal.  Burning trash has even more problems.  The biggest problem is that trash is a terrible fuel.  We pulverize coal into a dust and blow into the firebox.  This allows a hot and uniform fire.  Trash on the other hand contains wet mattresses, wet bags of grass, car batteries, newspapers and everything else you’ve ever thrown away.  And if you ever lit a campfire or a BBQ you know some things burn better than other things.  And wet things just don’t burn at all.  So some of this fuel entering the furnace can act like throwing water on a hot fire.  Which makes it difficult to maintain a hot and uniform fire.  They load fuel on a long, sloping grate that enters the furnace.  Mechanical agitators shake the trash down this grate slowly.  As the trash approaches the fire it heats up and dries out as much as possible before entering the fire.  Still the fire burns unevenly.  They try to keep the temperature above 1,000 degrees Fahrenheit (about 538 degrees Celsius) .  But they’re not always successful.

They can improve the quality of the fuel by processing it first.  Tearing open bags with machinery so people can hand pick through the trash.  They will remove things that won’t burn.  Then send what will burn to a shredder.  Chopping it up into smaller pieces.  This can help make for a more uniform burn.  But it adds a lot of cost.  So these plants tend to be expensive.  And nowhere as efficient as a coal-fired power plant (or nuclear power plant) in boiling water into superheated dry steam.  Also, raw trash tends to stink.  And no one really knows what’s in it when it burns.  Making people nervous about what comes out of their smoke stacks.  You add all of these things up and you see why less than half of 1% of our electricity comes from burning our trash.

This is why we generate approximately 87% of our electricity from coal, natural gas and nuclear power.  Coal and nuclear power can make some of the hottest and driest steam.  But making a hot fire or bringing a nuclear reactor on line takes time.  A lot of time.  So we use these as baseload power plants.  They generate the supply that meets the minimum demand.  Power that we use at all times.  Day or night.  Winter or summer.  They run 24/7 all year long.  Natural gas plants add to the baseload.  And handle peak demands over the baseload.  Because they don’t boil water they can come on line very quickly to pickup spikes in electrical demand.  Hydroelectric power shares this attribute, too.  As long as there is enough water in the reservoir to bring another generator on line.  The other 5% (wind, solar, geothermal, trash incinerators, etc.) is more of a novelty than serious power generation.

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Electricity, Heat Engine, Superheated Dry Steam, Coal-Fired Power Plant, Geothermal Power Plant and Waste-to-Energy Plant

Posted by PITHOCRATES - August 1st, 2012

Technology 101

Geothermal Power Plants and Waste-to-Energy Plants each produce less than Half of 1% of our Electricity

We produce the majority of our electricity with heat engines.  Where we boil water into steam to spin a turbine.  Or use the expanding gases of combustion to spin a turbine.  The primary heat engines we use are coal-fired power plants, natural gas-power plants and nuclear power plants.  The next big source of electricity generation is hydroelectric.  A renewable energy source.  In 2011 it produced less than 8% of our electricity.  These sources combined produce in excess of 95% of all electricity.  While renewable energy sources (other than hydroelectric) make up a very small percentage of the total.  Wind power comes in under 3%.  And solar comes in at less than 0.2% of the total.  So we are a very long way from abandoning coal, natural gas and nuclear power.

Two other renewable energy sources appear to hold promise.  Two heat engines.  One powered by geothermal energy in the earth.  The other by burning our garbage.  In a waste-to-energy plant.  These appear attractive.  Geothermal power appears to be as clean as it gets.  For this heat isn’t man-made.  It’s planet-made.  And it’s just there for the taking.  But the taking of it gets a little complicated.  As is burning our trash.  Not to mention the fact that few people want trash incinerators in their neighborhoods.  For these reasons they each provide a very small percentage of the total electric power we produce.  Both coming in at less than half of 1%.

So why steam?  Why is it that we make so much of our electrical power by boiling water?  Because of the different states of matter.  Matter can be a solid, liquid or a gas.  And generally passes from one state to another in that order.  Although there are exceptions.  Such as dry ice that skips the liquid phase.  It sublimates from a solid directly into a gas.  And goes from a gas to a solid by deposition.  Water, though, follows the general rule.  Ice melts into water at 32 degrees Fahrenheit (or 0 degrees Celsius).  Or water freezes into ice at the same temperature.  Water vaporizes into steam at 212 degrees Fahrenheit (or 100 degrees Celsius).  Or steam condenses into water at the same temperature.  These changes in the state of matter are easy to produce.  At temperatures that we can easily attain.  Water is readily available to vaporize into steam.  It’s safe and easy to handle.  Making it the liquid of choice in a heat engine.

Today’s Coal-Fired Power Plant pulverizes Coal into a Dust and Blows it into the Firebox

A given amount of water will increase about 1600 times in volume when converted to steam.  It’s this expansion that we put to work.  It’s what pushed pistons in steam engines.  It’s what drove steam locomotives.  And it’s what spins the turbines in our power plants.  The plumes of steam you see is not steam, though.  What you see is water droplets in the steam.  Steam itself is an invisible gas.  And the hotter and drier (no water) it is the better.  For water droplets in steam will pit and wear the blades on a steam turbine.  Which is why the firebox of a coal-fired plant reaches temperatures up to 3,000 degrees Fahrenheit (about 1,650 degrees Celsius).  To superheat the steam.  And to use this heat elsewhere in the power plant such as preheating water entering the boiler.  So it takes less energy to vaporize it.

To get a fire that hot isn’t easy.  And you don’t get it by shoveling coal into the fire box.  Today’s coal-fired power plant pulverizes coal into a dust and blows it into the firebox.  Because small particles can burn easier and more completely than large chunks of coal.  As one fan blows in fuel another blows in air.  To help the fire burn hot.  The better and finer the fuel the better it burns.  The better the fuel burns the hotter the fire.  And the drier the steam it makes.  Which can spin a turbine with a minimum of wear.

In a geothermal power plant we pipe steam out of the ground to spin a turbine.  If it’s hot enough.  Unfortunately, there aren’t a lot of geothermal wells that produce superheated dry steam.  Which limits how many of these plants we can build.  And the steam that the planet produces is not as clean as what man produces.  Steam out of the earth can contain a lot of contaminants.  Requiring additional equipment to process these contaminants out.  We can use cooler geothermal wells that produce wet steam but they require additional equipment to remove the water from the steam.  The earth may produce heat reliably but not water.  When we pipe this steam away the wells can run dry.  So these plants require condensers to condense the used steam back into water so we can pump it back to the well.  A typical plant may have several wells piped to a common plant.  Requiring a lot of piping both for steam and condensate.  You put all this together and a geothermal plant is an expensive plant.  And it is a plant that we can build in few places.  Which explains why geothermal power makes less than half of 1% of our electricity.

We generate approximately 87% of our Electricity from Coal, Natural Gas and Nuclear Power

So these are some the problems with geothermal.  Burning trash has even more problems.  The biggest problem is that trash is a terrible fuel.  We pulverize coal into a dust and blow into the firebox.  This allows a hot and uniform fire.  Trash on the other hand contains wet mattresses, wet bags of grass, car batteries, newspapers and everything else you’ve ever thrown away.  And if you ever lit a campfire or a BBQ you know some things burn better than other things.  And wet things just don’t burn at all.  So some of this fuel entering the furnace can act like throwing water on a hot fire.  Which makes it difficult to maintain a hot and uniform fire.  They load fuel on a long, sloping grate that enters the furnace.  Mechanical agitators shake the trash down this grate slowly.  As the trash approaches the fire it heats up and dries out as much as possible before entering the fire.  Still the fire burns unevenly.  They try to keep the temperature above 1,000 degrees Fahrenheit (about 538 degrees Celsius) .  But they’re not always successful.

They can improve the quality of the fuel by processing it first.  Tearing open bags with machinery so people can hand pick through the trash.  They will remove things that won’t burn.  Then send what will burn to a shredder.  Chopping it up into smaller pieces.  This can help make for a more uniform burn.  But it adds a lot of cost.  So these plants tend to be expensive.  And nowhere as efficient as a coal-fired power plant (or nuclear power plant) in boiling water into superheated dry steam.  Also, raw trash tends to stink.  And no one really knows what’s in it when it burns.  Making people nervous about what comes out of their smoke stacks.  You add all of these things up and you see why less than half of 1% of our electricity comes from burning our trash.

This is why we generate approximately 87% of our electricity from coal, natural gas and nuclear power.  Coal and nuclear power can make some of the hottest and driest steam.  But making a hot fire or bringing a nuclear reactor on line takes time.  A lot of time.  So we use these as baseload power plants.  They generate the supply that meets the minimum demand.  Power that we use at all times.  Day or night.  Winter or summer.  They run 24/7 all year long.  Natural gas plants add to the baseload.  And handle peak demands over the baseload.  Because they don’t boil water they can come on line very quickly to pickup spikes in electrical demand.  Hydroelectric power shares this attribute, too.  As long as there is enough water in the reservoir to bring another generator on line.  The other 5% (wind, solar, geothermal, trash incinerators, etc.) is more of a novelty than serious power generation.

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Neutrons, Electrons, Electric Current, Nuclear Power, Nuclear Chain Reaction, Residual Decay Heat and Pressurized Water Reactor

Posted by PITHOCRATES - July 18th, 2012

Technology 101

We create about Half of our Electric Power by Burning Coal to Boil Water into Steam

An atom consists of a nucleus made up of protons and neutrons.  And electrons orbiting around the nucleus.  Protons have a positive charge.  Electrons have a negative charge.  Neutrons have a neutral charge.  In chemistry and electricity the electrons are key.  When different atoms come together they form chemical bonds.  By sharing some of those electrons orbiting their nuclei.  In metals free electrons roam around the metal lattice of the crystalline solid they’re in.  If we apply a voltage across this metal these free electrons begin to flow.  Creating an electric current.  The greater the voltage the greater the current.  And the greater the work it can do.  It can power a television set.  Keep your food from spoiling in a refrigerator.  Even make your summers comfortable by running your air conditioner. 

We use electric power to do work for us.  Power is the product of voltage and current.  The higher each is the more work this power can do for us.  In a direct current (DC) system the free electrons have to make a complete path from the power source (an electric generator) through the wiring to the work load and back again to the power source.  But generating the power at the voltage of the workload required high currents.  Thick wires.  And a lot of power plants because you could only make wires so thick before they were too heavy to work with.  Alternating current (AC) solved this problem.  By using transformers at each end of the distribution path to step up and then step down the voltage.  Allowing us to transmit lower currents at higher voltages which required thinner wires.  And AC didn’t need to return to the power plant.  It was more like a steam locomotive that converted the back and forth motion of the steam engine into rotational power.  AC power plants generated a back and forth current in the wires.  And electrical loads are able to take this back and forth motion and convert it into useful electrical power.

Even though AC power allows us to transmit lower currents we still need to move a lot of these free electrons.  And we do this with massive electric generators.  Where another power source spins these generators.  This generator spins an electric field through another set of windings to induce an electrical current.  Sort of how transformers work.  This electrical current goes out to the switchyard.  And on to our homes.  Simple, really.  The difficult part is creating that rotational motion to spin the generator.  We create about half of our electric power by burning coal to boil water into steam.  This steam expands against the vanes of a steam turbine causing it to spin.  But that’s not the only heat engine we use to make steam.

To Shut Down a Nuclear Reactor takes the Full Insertion of the Control Rods and Continuously Pumping Cooling Water through the Core

We use another part of the atom to generate heat.  Which boils water into steam.  That we use to spin a steam turbine.  The neutron.  Nuclear power plants use uranium for fuel.  It is the heaviest naturally occurring element.  The density of its nucleus determines an element’s weight.  The more protons and neutrons in it the heavier it is.  Without getting into too much physics we basically get heat when we bombard these heavy nuclei with neutrons.  When a nucleus splits apart it throws off a few spare neutrons which can split other nuclei.  And so on.  Creating a nuclear chain reaction.  It’s the actual splitting of these nuclei that generates heat.  And from there it’s just boiling water into steam to spin a steam turbine coupled to a generator.

Continuous atom splitting creates a lot of heat.  So much heat that it can melt down the core.  Which would be a bad thing.  So we move an array of neutron absorbers into and out of the core to control this chain reaction.  So in the core of a nuclear reactor we have uranium fuel pellets loaded into vertical fuel rods.  There are spaces in between these fuel rods for control rods (made out of carbon or boron) to move in and out of the core.  When we fully insert the control rods they will shut down the nuclear chain reaction by absorbing those free neutrons.  However there is a lot of residual heat (i.e., decay heat) that can cause the core to melt if we don’t remove it with continuous cooling water pumped through the core. 

So to shut down a nuclear reactor it takes both the full insertion of the control rods.  And continuously pumping cooling water through the core for days after shutting down the reactor.  Even spent fuel rods have to spend a decade or two in a spent fuel pool.  To dissipate this residual decay heat.  (This residual decay heat caused the trouble at Fukushima in Japan after their earthquake/tsunami.  The reactor survived the earthquake.  But the tsunami submerged the electrical gear that powered the cooling pumps.  Preventing them from cooling the core to remove this residual decay heat.  Leading to the partial core meltdowns.)

Nuclear Power is one of the most Reliable and Cleanest Sources of Power that leaves no Carbon Footprint

There is more than one nuclear reactor design.  But more than half in the U.S. are the Pressurized Water Reactor (PWR) type.  It’s also the kind they had at Three Mile Island.  Which saw America’s worst nuclear accident.  The PWR is the classic nuclear power plant that all people fear.  The tall hyperboloid cooling towers.  And the short cylindrical containment buildings with a dome on top housing the reactor.  The reactor itself is inside a humongous steel pressure vessel.  For pressure is key in a PWR.  The cooling water of the reactor is under very high pressure.  Keeping the water from boiling even though it reaches temperatures as high as 600 degrees Fahrenheit (water boils into steam at 212 degrees Fahrenheit under normal atmospheric pressure).  This is the primary loop.

The superheated water in the primary loop then flows through a heat exchanger.  Where it heats water in another loop of pumped water.  The secondary loop.  The hot water in the primary loop boils the water in the secondary loop into steam.  As it boils the water in the secondary loop it loses some of its own heat.  So it can return to the reactor core to remove more of its heat.  To prevent it from overheating.  The steam in the secondary loop drives the steam turbine.  The steam then flows from the turbine to a condenser and changes back into water.  The cooling water for the condenser is what goes to the cooling tower.  Making those scary looking cooling towers the least dangerous part of the power plant.

The PWR is one of the safest nuclear reactors.  The primary cooling loop is the only loop exposed to radiation.  The problem at Three Mile Island resulted from a stuck pressure relief valve.  That opened to vent high pressure during an event that caused the control rods to drop in and shut down the nuclear chain reaction.  So while they stopped the chain reaction the residual decay heat continued to cook the core.  But there was no feedback from the valve to the control room showing that it was still open after everyone thought it was closed.  So as cooling water entered the core it just boiled away.  Uncovering the core.  And causing part of it to melt.  Other problems with valves and gages did not identify this problem.  As some of the fuel melted it reacted with the steam producing hydrogen gas.  Fearing an explosion they vented some of this radioactive gas into the atmosphere.  But not much.  But it was enough to effectively shut down the U.S. nuclear power industry. 

A pity, really.  For if we had pursued nuclear power these past decades we may have found ways to make it safer.  Neither wind power nor solar power is a practical substitution for fossil-fuel generated electricity.  Yet we pour billions into these industries in hopes that we can advance them to a point when they can be more than a novelty.  But we have turned away from one of the most reliable and cleanest sources of power (when things work properly).  Using neutrons to move electrons.  Taking complete control of the atom to our make our lives better.  And to keep our environment clean.  And cool.  For there is no carbon footprint with nuclear power.

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Anti-Nuclear Crowd yearns for Chernobyl in Japan

Posted by PITHOCRATES - March 13th, 2011

Enough of Exploiting Japan’s Disaster for Political Gain

First it was an environmentalist saying global warming caused the 8.9 magnitude earthquake.  A sure grasping of straws in their quest to move man back into the cave.  Then it was anti-nuclear power Rep. Edward Markey of Massachusetts, the senior Democrat on the House Natural Resources Committee, who said we should learn from Japan’s near Chernobyl-like disaster.  And move back into the cave.  And now it’s Senator Joe Lieberman, chairman of the Senate Homeland Security and Governmental Affairs Committee, chiming in (see “Put the brakes” on nuclear power plants: Lieberman by Will Dunham posted 3/13/2011 on Reuters).

“I don’t want to stop the building of nuclear power plants,” independent Senator Joe Lieberman, chairman of the Senate Homeland Security and Governmental Affairs Committee, said on the CBS program “Face the Nation.”

“But I think we’ve got to kind of quietly put, quickly put the brakes on until we can absorb what has happened in Japan as a result of the earthquake and the tsunami and then see what more, if anything, we can demand of the new power plants that are coming on line,” Lieberman added.

Put the brakes on?  What, he wants to slow down from the breakneck speed we’re building new nuclear power plants and bringing them on line?  That’s going to be pretty hard to do considering the speed we’re going at.  I mean, when was the last time we built a nuclear power plant in the United States?

It’s not about what happened at the Fukushima Power Plant, it’s about what hasn’t Happened

We’re missing the big picture here.  The nuke plants didn’t kill or wipe out cities yet.  Like the earthquake-tsunami one-two punch has.  Let’s not lose sight of that little fact (see Nuclear Overreactions posted 3/14/2011 on The Wall Street Journal).

Part of the problem is the lack of media proportion about the disaster itself. The quake and tsunami have killed hundreds, and probably thousands, with tens of billions of dollars in damage. The energy released by the quake off Sendei is equivalent to about 336 megatons of TNT, or 100 more megatons than last year’s quake in Chile and thousands of times the yield of the nuclear explosion at Hiroshima. The scale of the tragedy is epic.

Yet the bulk of U.S. media coverage has focused on a nuclear accident whose damage has so far been limited and contained to the plant sites. In simple human terms, the natural destruction of Earth and sea have far surpassed any errors committed by man.

So in the grand scheme of things, the Japanese nuclear plants are minor players in this great tragedy.  Even that embellishes their role.  Much of Japan lies in waste.  Because of the earthquake and the tsunami.  The nukes so far have been innocent bystanders in the death and destruction.  But it’s all we focus on.  Even though they haven’t really done anything yet.  But under the right set of circumstances that don’t currently exist…they could.   So we use the big ‘what if’ to further shut down the already shutdown American nuclear power industry.  Why?  Simple.  Because congress can’t place a moratorium on earthquakes or tsunamis.

So back to that question.  When was the last time we built a nuclear power plant in the United States?

But more than other energy sources, nuclear plants have had their costs increased by artificial political obstacles and delay. The U.S. hasn’t built a new nuclear plant since 1979, after the Three Mile Island meltdown, even as older nuclear plants continue to provide 20% of the nation’s electricity.

So Senator Joe Lieberman wants to tap the breaks on a car that’s been parked and in the garage since 1979.  How does he do it?  Where does the genius come from?

No coal.  No oil.  And now no nukes.  Translation?  No power.  I guess we should practice our hunting and gathering skills.  Because we’re going to need them when we move back into the cave.  Of course, we’ll have to eat our food cold.  You know.  Carbon footprint.  From those foul, nasty, polluting campfires.

In America, Coal, Oil and Nuclear Power all Wear Black Hats

Some in Congress just love the planet so much.  They want to get rid of coal and oil and replace them with clean energy.  Which means nuclear power.  Because windmills and solar panels just won’t produce enough power.  Especially when they want us all driving tiny little electric cars that are going to suck more juice off our strained electrical grid.  And just how strained is our electric grid?  Remember the Northeast Blackout of 2003

High summer currents caused power lines to sag into untrimmed trees.  As lines failed some power plants dropped off the grid.  This strained other power plants.  And other power lines.  More lines failed.  More plants dropped off the grid.  This cascade of failures didn’t end until most of New York, Pennsylvania, Ohio, Michigan and Ontario lost power.  It was huge.  And if you experienced that hot, stifling, August blackout, you know that windmills wouldn’t have helped.  There was no breeze blowing.  And solar panels wouldn’t have helped you sleep at night.  Because there’s no sun at night.  No.  What would have helped was some big-capacity power generation.  Like a coal plant.  An oil plant.  Or a nuke plant.

Energy demands increase with population.  And with electric cars.  We need more generation capacity.  And the only viable green solution is nuclear power.  And now we’re dilly dallying about the dangers of clean nuclear power because of what didn’t happen in Japan (see Japan Does Not Face Another Chernobyl by William Tucker posted 3/14/2011 on The Wall Street Journal).

Rep. Ed Markey (D., Mass.), a longtime opponent of nuclear power, has warned of “another Chernobyl” and predicted “the same thing could happen here.” In response, he has called for an immediate suspension of licensing procedures for the Westinghouse AP1000, a “Generation III” reactor that has been laboring through design review at the Nuclear Regulatory Commission for seven years.

Talk about the irony of ironies.  The Soviet-era nuclear reactor at Chernobyl was the most dangerous ever used.  That reactor went ‘Chernobyl’ because of its design.  A graphite core that caught fire.  And no containment vessel that let plumes from that fire spread radioactive fallout throughout western Russia and Europe.  If the Soviets had used the type of reactor that’s getting all the media attention in Japan, there would have been no Chernobyl disaster.  And now the irony.  Rep. Markey wants to suspend licensing of the world’s safest nuclear reactor (the Generation III) by citing the world’s most dangerous reactor that Japan doesn’t even use. 

But facts don’t matter when you’re just against nuclear power.  No matter how safe the Generation III design is.  Or the fact that it doesn’t even need cooling pumps. 

On all Generation II reactors—the ones currently in operation—the cooling water is circulated by electric pumps. The new Generation III reactors such as the AP1000 have a simplified “passive” cooling system where the water circulates by natural convection with no pumping required.

Despite this failsafe cooling system, there are calls to stop the licensing.  To put the brakes on.  To move back into caves.  All because of what didn’t happen at Fukushima.  What didn’t happen at Three Mile Island.  But what did happen in a Hollywood movieThe China Syndrome.  (But that’s a whole other story.)

If a meltdown does occur in Japan, it will be a disaster for the Tokyo Electric Power Company but not for the general public. Whatever steam releases occur will have a negligible impact. Researchers have spent 30 years trying to find health effects from the steam releases at Three Mile Island and have come up with nothing. With all the death, devastation and disease now threatening tens of thousands in Japan, it is trivializing and almost obscene to spend so much time worrying about damage to a nuclear reactor.

What the Japanese earthquake has proved is that even the oldest containment structures can withstand the impact of one of the largest earthquakes in recorded history. The problem has been with the electrical pumps required to operate the cooling system. It would be tragic if the result of the Japanese accident were to prevent development of Generation III reactors, which eliminate this design flaw.

Looking at Japan with Awe and Reverence

Japan has been nuclear since 1966.  They now have some 53 nuclear reactors providing up to a third of their electricity.  Yes, Japan lies on the Ring of Fire.  Yes, Japan gets hit by a lot of tsunamis.  And, yes, they now have a problem at a couple of their reactors.  But the other 50 or so reactors are doing just fine.  Let’s stop attacking their nuclear program.  So far they’ve done a helluva job.  And the Japanese know a thing or two about nuclear disasters.  They lived through two.  Hiroshima.  And Nagasaki.  Which make Chernobyl look like a walk in a park.  If anyone knows the stakes of the nuclear game, they do.  And it shows.

We should be looking at Japan with awe and reverence.  If they can safely operate nuke plants on fault lines and in tsunami alley, then, by God, we should be able to do it where things aren’t quite as demanding.  And should.  It is time we put on our big-boy pants and start acting like men.  Before we give up on all energy and move back into the cave.  And down a notch or two on the food chain.

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