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Here is a chance to understand a new clean way of making electricity from coal, APFBC.  While much of the information in other parts of this site is designed for people familiar with power plants and how they work, this page is written for, well, regular folks like you and me.

Don't be embarrassed!

Don't PANIC!

Most people haven't a clue about such weird things as "thermodynamics," or "heat transfer," or other mysteries of life, such as why the TV clicker always ends up lost. Engineers, of course, thinking themselves superior beings that evolved on an entirely different planet sort of automatically know these things.  Well, maybe not where the clicker is, but all the other important stuff.   We trapped one of them, and forced him to explain how this APFBC thing works.  Here's his tale:

We engineer-types tend to chatter to each other in our own alien language, "thermodynamics-ese," which makes our explanations of how things work ... well...boring to you mere mortals.  I mean, how many TV sitcoms have you seen that feature us engineer-types explaining enthalpy changes through a turbine two-row governing stage?  Heck, even I'm bored, and I'm writing this.

Actually, what we do is really pretty neat stuff once you get to understand it a little better.  After all, this is all about why the lights go on when you flick the switch, how we make equipment efficient to keep the cost of generating electricity low, and how we can upgrade equipment to make it much more friendly to the environment.  

Basically, engineers make the machines that... well...make the electricity.  It's just that we don't often take the time to translate HOW we do it into terms that make sense to 99.928 percent of the rest of the world.

Part of the problem in understanding how we make electricity is the special code words we use when we describe power plants.  If you knew the words, you'd get a much better idea of what it is we're doing, and why it is important to you.  I'll try to correct that now, and talk about what that "APFBC thing" up above there at the top of the page, right there in the title ... is.

Ok, here's the scoop: it's a nicer way to keep your electric lights lit.

APFBC is simply a new way to make electricity. It's clean. It reduces the waste of our energy resources. It generates electricity at low cost. That's it. It's another type of power plant. That's all.  However, APFBC also has a name that will make your eyes roll-up way back into your head far enough to give you a head-ache. Engineers often use precise technical words to describe things as complex as the kinds of machines that generate your electricity.  Some of these have such long names, so use "nicknames" like "APFBC" for them instead. APFBC is just like that, a nickname for a very long series of technical terms. You see, "APFBC" is a nickname for:  "advanced circulating pressurized fluidized bed combustion combined cycle."  Whew. Well, we'll get to defining all those strange words later. At least now you know why I had wanted to ease you into this. The words that this nickname represents are probably easily known to only a few scientists and engineers in the power industry, but if you have the courage to read on, you will soon know what they mean, too.

For now, just think of APFBC as a new type of power plant to make electricity.

From here on, my discussion now goes steadily downhill, because now I'm going to toss in some of that science stuff.  However, if you stay with me on this, you will actually learn something about this nifty new way to keep the lights lit.

I hope you enjoy the rest of this explanation.  It's pretty cool science.

What You'll Find If You Continue Below:

Be kind to me, keep me in the non-technical area below:

• What is an APFBC?
• High Energy Efficiency
• Excellent Environmental Performance
• Low-Cost Electricity
• So Then, Just What Does the Nickname "APFBC" Mean?
  (hey, isn't that how I got to here in the first place?)

or....
Okay, I'm brave  (or lack common sense):  forget this simple stuff, and
send me right on to that TECHNICAL discussion!

What Is an APFBC?

APFBC is a new way of making electricity from coal.   It is very efficient and clean.  APFBC will allow your electric company to make electricity inexpensively, so your electric bills stay low.

Coal is VERY important to the United States.  It is your electric supply, and the anchor that keeps electric prices low.  All of the other types of energy sources used to make electricity COMBINED do not make as much electricity as does coal.  In the U.S., coal is electricity.  Coal is a secure source of abundant energy.  Since almost every other type of fossil fuel costs more than coal, it is very likely that the price you pay for electricity is held to its lowest when coal plants provide a large proportion of your electricity; when you read about electric prices surging, you will most likely find that it was due to the need to use much more expensive fuels to make electricity during peak electric demand periods. 

The core of an APFBC plant is a special type of jet engine.   That's right, the same kind of engine that pushes airplanes through the sky can also be strapped to the ground and instead be made into a device to push a generator around to make electricity.

Jet engines are very efficient, but most jet engines use expensive fuels, like natural gas or oil.  This isn't necessary with APFBC.  APFBC uses a jet engine in a special kind of power plant that allows it to operate on low-priced coal instead.  In addition, APFBC is so efficient that it needs less coal than other coal plants.  APFBC uses an inexpensive fuel, and it needs less of that fuel than other plants.  APFBC is a way of keeping electric cost low.

Because it wastes less fuel, and because it uses coal in a way that is exceptionally clean, APFBC is a good neighbor.  It allows your electric company to use America's most abundant source of energy while preserving the environment.

Right now, APFBC is still under development.  That means engineers and scientists are testing the components that make up an APFBC system.   But this testing will be finished soon.  In just five short years, your electric company will be able to buy this type of power plant.

Click on picture to enlarge

If you were to strip away the walls of the building, take away the steel girders, and show the inside of an APFBC plant, there would be a lot of pipes and huge tanks inside, as shown in the illustration below.  Such a plant is BIG.  A man would be about the height of the red square lying at the bottom middle of the picture.

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High Energy Efficiency

Energy efficiency is a measure of how good an engine is in converting the chemical energy in its fuel into electricity.  The higher the efficiency, the better.  APFBC is attractive because it has such superior energy efficiency.  It can be easily adapted to improve the operations of an existing power plant.  High energy efficiency means it needs much less fuel to make your power, making it less costly to produce your electricity.  The improvement in efficiency is huge, like getting a 1/3 improvement in your car's gas mileage.

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Excellent Environmental Performance

APFBC's effect on the environment is excellent.   APFBC is a good, clean neighbor.

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Low-Cost Electricity

Repowering an existing electric plant with clean APFBC technology will cost about the same as building an old-style electric plant.  For the same amount of money, you get a much cleaner, more energy efficient power plant.   Since it is more efficient, it burns less fuel, making it cheaper to run.   This means that the cost of making electricity is kept low, keeping your electric bills under control.

What does it cost for a plant like this?  Well, we don't think you are likely to rush out and buy one on your own.   It would cost your electric company a lot of money, and you probably can't afford the same mortgage <grin>.  Power plants are huge, and your electric company has a large investment in buying and operating them.  How much does it cost?  Well, you could upgrade an existing power plant that originally produced a city's worth of power (120,000 kilowatts worth), and add APFBC to it.  This could increase the plant's output to about 227,000 kilowatts, powering all the new homes and industry that make our economy grow.  Doing that would cost $180,000,000. That's the kind of investment it takes to make your electricity cheaper!  And, that's why we, at least, will continue to buy our electricity from the electric company, thank you.

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So Then, Just What Does the Nickname "APFBC" Mean?

Well, we promised. The letters "APFBC" are an nickname for a particular type of coal-fueled electric power plant:

"Advanced circulating Pressurized Fluidized Bed Combustion combined cycle"

We warned you, didn't we?  Its a real jaw-breaker of a name...

...but, in spite of that name, it really is not all that difficult to decipher -- at least once you know how engineers use these special terms.  You're still curious, huh?  Okay, let's break it down.  Here's what it means to engineers:

Advanced:

Click on picture to enlarge

APFBC uses the very latest high-temperature jet engine at its core, which makes it very efficient (it uses special high-strength metals and cooling that let it run at temperatures that would easily melt ordinary steel, and were you able to look inside, would be so dazzling white-hot that you would need welder's glasses to look).  The type of jet engine is like that in an airplane, but instead of pushing an airplane through the air, the jet acts sort of like a pinwheel that spins and turns a generator, making electricity instead.  Here is a picture of the kind of jet engine used in an APFBC plant:

Circulating:

An APFBC plant gets its energy from burning coal.  The hot coal and ash burning inside the APFBC are blown by fans to circulate around pipes that make high-temperature steam (the pipes that carry the steam are even hotter than red-hot electric stove burner coils set at maximum; if they weren't hidden inside, they would glow bright yellow).  The coal and ash that are blown around are pebble-sized, about the size of aquarium gravel.  There are also limestone pebbles of about the same size that are put into the APFBC (this limestone takes out the pollutants).

No, the coal doesn't burn in the jet engine; the pebbles would damage the expensive blades inside the jet.  Instead, APFBC burns the coal pebbles in a separate tank that can handle these solids.  The APFBC system makes a good fuel gas from the coal, and this gas is filtered to remove all the pebbles and dust.  The gas is very clean.  The jet engine burns this clean fuel gas with hot air.

Pressurized:

For high efficiency, the system operates at high pressure, greater than that which runs jackhammers.  The high pressure helps make APFBC efficient, and keeps cost down.

Fluidized Bed:

Hot coal, limestone, and ash pebbles, about the size of aquarium gravel, are lifted by powerful fans that blow air under the pile of pebbles. This pile of pebbles is called the bed.  This air, rushing up underneath the pebbles, lifts the pebbles, making them flutter upward like a swarm of snowflakes lifted by the wind.  This makes the floating solids look a lot like a boiling liquid, bubbling and seething.  A fluidized bed makes the combustion work well, and makes it easy to take out the heat from the burning coal.  Of course, the bed is very hot inside.  If you could see inside, the coal, ash, and limestone glow white hot.   It would be so bright that you'd need tinted glasses to look.

The fluidized bed also makes it easy to capture sulfur from the coal, which prevents the sulfur from ever becoming a pollutant.   Instead, the sulfur gets tied into the limestone, and carried away with the ash as non-polluting solid compounds.

In ordinary furnaces coal is burned at high temperature.  The high-temperature burning makes a lot of another kind of pollutant called NOx.   However, in APFBC, the fluidized beds operate at a much lower and very constant temperature, so little of that pollutant is produced.

The gas carrying heat from the fluidized bed is sent to the jet engine, which helps make APFBC efficient.  However, the jet engine cannot tolerate dust, or its expensive blades would be damaged.  Thus, an APFBC also employs excellent high-temperature filters.  These are made of a porous ceramic that lets the clean fuel gas and air through, but stops the dust.  These are such good filters that there is almost no dust that escapes up the chimney.

An APFBC is also very efficient.   This means that less coal is needed to make electricity than in today's power plants.  Burning less coal means less mining, fewer rail cars, and fewer emissions for every kilowatt generated.

Because of these features, an APFBC is quite friendly to the environment, which makes an APFBC power plant a good, clean neighbor.

Combustion:

An APFBC burns coal.  Most of your electricity is made by burning coal.  Coal is an inexpensive fuel, and America has abundant supplies of it, with huge reserves of this energy source.  That means that we don't have to import energy; we have it right here at home.  But since APFBC is so very efficient, much less coal is needed to make electricity; to make an analogy, APFBC has much better "gas mileage," using 30 percent less fuel than today's generating stations.  That means it is inexpensive to operate, and produces less pollution.

Combined Cycle:

For the very highest efficiency levels, as much of the coal's energy as possible must be used, even energy that would ordinarily go up the chimney.  The heat from the jet engine exhaust is used again.   Energy is recovered by using that heat to make high-pressure steam instead of just wasting it by sending it up the chimney.  This steam spins another kind of pinwheel called a steam turbine, which is an efficient way to run an electric generator.  Only after almost all of the energy of the exhaust is used up is it sent up the chimney. An efficient power plant like this, which has both a jet engine and a steam turbine to recover much of the exhaust heat, is called a combined cycle.

...Now you know what APFBC is!

Hey....I LOVE THIS STUFF.  I'M READY FOR MORE!
SEND ME TO THE TECHNICAL DISCUSSION!