Misconceptions About Coal Fired Power Generation

Posted on Fri 02/20/2009 by


I have specifically left this post separate from the others, because it needs a full post of its own.

We have been led to believe that coal fired power plants are what amounts to the main cause in what will amount to global catastrophe.
The only real catastrophe that will result will be when ill informed Governments who have swallowed this lock stock and barrel actually start closing those plants. Only then will the realisation sink in that there is nothing that can replace them in the near term, and even in the long term. The catastrophe will be to those politicians pointing at the closing of the plant as being one step towards saving the Planet. The people who will then have to do without electricity will very quickly boot those politicians right out of office. Catastrophe for the politicians yes, but the real catastrophe will be for those people with no electricity.

The power grid right now is straining under the effects of demand outstripping supply, and demand is growing at a rate of around 2%. That might sound small, but what is coming on line are small plants that just cannot take up that demand on a like for like basis, and as more of those older coal fired plants reach the ends of their useful lives, what will happen when they are decommissioned is that a large chunk of supply is removed, with nothing comparable to replace it.

Again, the readers that way inclined will point directly at an ‘agenda’ I might have, but I don’t have an agenda.

So, those coal fired power plants.

What do they do, and how do they do it?

I detailed in this post how a coal fired plant produces electricity. Take the link and look at the diagram, and read the text.
A multi stage turbine drives a large generator to produce huge amounts of electricity. This unit can weigh from 250 to 400 tons, and it has to be that big to produce the huge amounts of electricity that these plants provide.
To turn over the huge weight of that turbine, high temperature high pressure steam is needed to actually drive it.
That steam is generated in a huge and complex boiler. To heat the water, coal is burned.
The coal is crushed and fed into the furnace. Crushed so it burns more easily, and more quickly, generating a higher heat.

So, just how much coal does one of those huge plants burn? By huge here I mean those big plants that can produce 2,000 MegaWatts (MW) of power.

Those large plants burn on average between 10,000 and 15,000 tons of coal each and every day, and go and read that sentence again.
A large plant can consume, and wait for it, more than 6 Million tons of coal each year.
I detailed in this post just how much Carbon Dioxide (CO2) is produced from the burning of coal for this purpose, and as hard as it might be to believe one ton of coal burned produces 2.86 tons of CO2. Go and read the post at the link to see just how.
I don’t make this stuff up. It’s all the factual truth.

So, then, just how many of these coal fired power plants are there in the U.S..?

About 800 or so. There are nearly 1500 generators in all, Some of the smaller plants have only one generator, and some of the larger ones will have two or three generators.
The nameplate capacity of all these plants total out at around 340,000 MW. That capacity differs somewhat from Summer to Winter.

How much electricity do they supply?

I’m going to express this total in KiloWattHours (KWH) because that’s what you see on your electricity utilities bill.
Those coal fired power plants produce 2,200,000 Million KWH of power that is actually consumed by all users. In long figures that is 2,200,000,000,000 KWH.

The big question you’re all waiting for.
How much coal do all of these plants burn each year to produce that amount of electricity?

Read it slowly.

1.1 billion tons. Longhand 1,100,000,000 tons of coal burned each and every year.

Consequently from that, at the rate of 2.86 tons of CO2 per ton of coal, then the emission of CO2 from all of those plants amounts to 3.15 Billion tons of CO2. 3,150,000,000 tons.

What needs to be taken in context with this is that the U.S. generates one quarter of the Planet’s electricity. Keep in mind that the U.S. produces just under 50% of its power from coal fired means while the average for the rest of the Planet is closer to 80%.
Add the rest of the World’s CO2 emissions(just from coal fired power plants) to that of the US, and that total CO2 emissions from coal fired power plants alone now totals 14.5 Billion tons.

The emissions from those coal fired plants is roughly 30% of all emissions, so the total emissions from all sources on the Planet roughly amounts now to 50 Billion tons of CO2 released into the atmosphere each and every year.

Now, just writing down those huge numbers might make people tend to believe that it defeats my own argument. Quite the contrary in fact.

The amount of CO2 in the atmosphere in total is around 380 parts per million. This equates to 0.04% of the total atmosphere. This gas, CO2, goes to make up part of that greenhouse gas layer, but even then CO2 makes up only 2% of that layer. The largest of the greenhouse gases is water vapour, and that makes up 97.5% of that greenhouse gas layer.

If this level of CO2 in the atmosphere is so incredibly low, so much so that it is almost inconsequential, please tell me HOW, just HOW can it contributing to global warming on such a huge scale that we are being told.

Okay then, let’s get back to the U.S. levels and deal with them.
Even were we to completely shut down every coal fired plant in the U.S. without bothering about the consequences of doing just that, the U.S. would still be emitting twice that amount of CO2 every year, and in so doing, all that would be achieved would be a 5% reduction in Worldwide total emissions. That’s shutting down every coal fired plant in the Country. Half the total power supply for the U.S. for a 5% cut in global total emissions.
All right then, let’s compare one coal fired plant to a wind plant, and then also to a solar plant.

For the coal fired plant, I have selected the Bruce Mansfield plant in Pennsylvania, not because they are large emitters, but just because that plant is the one I have always used as a reference.
Bruce Mansfield coal fired power plant produces 2,741MW nameplate capacity power. It burns more than 6 million tons of coal each year, again, average for these large plants, and in so doing emits 18 million tons of CO2 each year. It provides 22,000 Million KWH of used power each year.

For the Wind plant, I’m using the as yet unbuilt Cape Wind Complex in Nantucket Sound. Consider this. Each tower stands as high as the Statue of Liberty at the hub. The 3 bladed fan attached to that adds height so at the top of the blade rotation, it is 440 feet, 100 feet higher than Liberty. The nacelle the blades are attached to weighs in the vicinity 50 tons and produces a nameplate capacity of 3 MW, that’s if the wind blows consistently at 16 MPH.
Cape Wind has 140 of these towers spread out over 24 square miles, will cost $1.2 Billion dollars, and will produce around 1,100 Million KWH a year, at an efficiency rating (at best) of 30%.
Bruce Mansfield plant produces this same amount of power every 18 days.

For the Solar plant, I’m using the as yet unbuilt Abengoa Solana Plant at Gila Junction near Phoenix in Arizona. The plant is a solar thermal plant using focused mirrors to heat water to steam to drive a small turbine/generator. The focused mirrors also heat molten salt so the water can be passed through this to heat the water to steam also.
This plant will also cost around $1.2 Billion. It has a nameplate capacity of 280MW, and also operating at only 30% efficiency will deliver 760 million KWH of power each year.
Bruce Mansfield plant produces this same amount of power every 12 days.

Again, you say the amounts of CO2 emitted serve to defeat my own argument.
Consider this very closely.
The average age of all those coal fired power plants in the U.S. is 45 years, and around 50 years is the expected life of these plants. All that tells me is that an awful lot of these plants are approaching the end of their lives, and there is nothing of the scale required to replace them when they do reach that time.
Consider this also.
If the average age of all those coal fired plants is 45 years, then they have been working at their capacity for that long. So, in effect the U.S. has been emitting that amount of 3.15 Billion tons of CO2 for all that time, around half a Century in fact, and more.

Why is it that all of a sudden in the last decade or so that we are being told that CO2 is causing catastrophic global warming?

The Earth’s atmosphere comprises 0.04% of CO2. Nitrogen goes to make up 76.55% and Oxygen makes up 20.55% of that same atmosphere.

Carbon Dioxide – 0.04%.

Every one of the above figures are easily available. All you have to do is look. Before you believe what people who actually do have an agenda tell you, be careful you also look at just what it means, and just what the consequences will be.
Coal fired power plants are not the villains they are made out to be. Without them, there will be no electricity at all. What will the consequences of that be? More catastrophic than what any of us have been told.

No electricity. Think about that for a minute.