How Clean Coal Works

I possibly can be. I'm in favor of renewable energy sources. I'm also in favor of pursuing research into nuclear fusion as a power source, if in fact that is possible to make a sustainable, effective power source. I'm very much in favor of getting off of all fossil fuels, particularly coal. However, I will do my best to discuss this topic without bias,

in other words, without just constantly spitting on coal. And even an advocate for clean energy like me has to admit there are enormous challenges in the way of weaning ourselves off of coal and other fossil fuels as an energy source. There are big things we have to be

able to make work for that to happen. So we're gonna talk about those two because it's important to look at these problems from a big picture perspective and to not just ignore the very real hurdles that are in our way, because if we do, if we ignore those hurdles, then we set ourselves up for failure when we try to change things. If we acknowledge the challenges, then maybe we can figure out a way of getting around them,

over them, or through them. So what is coal. I've already mentioned that it's a fossil fuel, but what that really means is that originally comes from or gain nic material, most notably pete. Pete is a large source of a

lot of the coal that we use today. So this organic material accumulates, it gets buried over times of animals die, plants die, they decompose, they get buried by sand and other stuff, and centuries go by and more and more layers build up around this material, and the material then starts to compact under all that pressure, and the temperature grows because it's under pressure like the Wonderful Queen and

uh David Boisong. And then as it has all of this pressure and heat, the material hardens into a rock like substance and it turns into coal. So to call it coal, it has to contain a significant amount of carbonaceous material by weight or volume. Carbonaceous just means that it has to contain carbon or carbon compounds. The amount and type of carbon and coal determines how much energy the coal contains, and really, to us, what that mostly means is how much heat the coal is capable of

producing when it is burned when it's combusted in a furnace. This, in turn is dependent upon a few things, including how much heat and pressure went into creating the coal in the first place. There are a lot of different ways of classifying coal, but there are four main ranks of coal. There's anthracite coal, and that has at least eight ton carbon in it. This coal has the highest heating value of coal, and there ain't a lot of it. It's

not plentiful in the United States. Less than one percent of all the coal mind in the country ranks as anthracite. The one place in the United States where it is mined right now is Pennsylvania. This coal is used nearly exclusively by the metals industry. Coal blaze an important part in producing various types of metal and metallurgy. Then you have by tuminous coal. Bituminous coal contains between forty five to eighty six carbon, and this makes up nearly half

of all the coal mind in the United States. Specifically, it's around for of all the coal we mine here in the US. This is the coal that's used primarily for coal burning power plants for generating electricity. It's also used in iron and steel industries. Five states in the United States produced nearly all of the coal for the entire country. Those five states are West Virginia, Pennsylvania, Kentucky, Illinois, and Indiana. Then you have sub bituminous coal that contains

between thirty five carbon, so as less carbon. You'll notice in these ranks were going down by the amount of percentage of carbon the material. It also has a lower heating value. It doesn't burn as hot as bituminous coal. It makes up about for of all coal production in the US. So sub by tuminous and bituminous coal make up when you add it up. And remember the anthracite makes up less than one percent, so the rest of it is made up of lignite. As the last rank,

it contains only twenty carbon. This stuff can convert into synthetic natural gas with some processing. We also call it sin gas s y n G A S, and i'll talk about that again a little bit later in this episode. Now, human beings have been using coal for at least three thousand years, though many early references to coal actually are referring to charcoal, not to the stuff we mine out of the ground. Charcoal is not the same thing as coal.

Charcoal is what you get when you remove water and several compounds from wood, and typically you do this in a low oxygen environment, and you would apply a lot of heat to the wood. So if it were a high oxygen environment, the wood would catch fire and burn, but because it's low oxygen, that reaction can't happen. We remember the triangle that you need in order to make fire. You have to have heat, and you have to have fuel,

and you have to have an oxidizer, typically oxygen. So you're not you're you're you're heating up in a low oxygen environment, you're essentially cooking the wood. The technical term

for this would be pyrolysis. So again you're not burning it, you're just removing moisture and heating up the wood in this low oxygen environment, and you end up with about a quarter of the mass that you started with, or a quarter by weight, So all those compounds in the water make up a lot of the weight, the majority of the weight of the wood, so you end up with something that's about the weight of whatever you started with.

Now we've used coal, the mineral, the stuff we mine for a really long time, uh, But the widespread, large scale use of coal, the industrial use of coal, really didn't get going until the eighteenth century. That's when you had inventors like Abraham Darby who developed methods for using

coal in blast furnaces. And the Industrial Revolution, which really began in England and then spread throughout the rest of the world, saw an enormous need for coal, and that pushed the mining industry from being sort of a modest effort. And there were mines that existed before the Industrial Revolution, but the need for coal was much more modest then,

so they were very much surface minds. At this point, the need for coal was voracious, so mine started getting deeper and going further and requiring way more manpower to operate. It became an enormous enterprise, employing thousands of people, tens of thousands of people. Coal mining became a lucrative but dangerous business. Miners encountered deadly gases, some of them explosive, so if you were to create a spark while mining, you could ignite that explosive gas and have have a

true catastrophe. Some gases are poisonous. Uh, there was always an issue with flooding. That was always a danger with mine chefts. There was also the possibility of mine chefts collapsing, but the demand for coal created enough of a reward to merit the risk, at least in the minds of the coal mine owners, if not the actual miners who

were doing the work. Britain led the way in coal mining in this early time in the eighteenth century, and because it was plentiful, lower rank coal in England, not the stuff that we would use today to generate electricity, would frequently be used as a fuel to warm homes in coal furnaces. So you have a furnace, throw some coal in there and that was what would generate heat.

That created a lot of air pollution in England. London, which had a reputation for heavy fogs, was frequently blanketed in smog, and smog, of course, is made up of particulate matter that comes out of burning fossil fuels, particularly coal. This peaked in nineteen fifty two with the Great Smog of London, which produced a smog so thick and so persistent it reduced visibility drastically to just a few meters, and it had an enormously negative impact on citizen health.

People started developing really terrible respiratory illnesses as a result. So what does burning coal produce, apart from heat that we can use in applications like boiling water into steam to turn a turbine and generate electricity. Well, the burning process breaks the chemical bonds between the atoms and coal. Those molecular bonds get broken and that's what releases energy and also several potential pollutants, including contaminants that could be

part of the coal. That can include stuff like mercury, which is a toxic heavy metal. Mercury is dangerous stuff. It can damage health in numerous ways. It can cause damage to the nervous system, the digestive system, the immune system. In fourteen, US coal plants emitted more than forty five thousand pounds of mercury coal plants are responsible for of all mercury emissions in the United States, so that's a big one. Sulfur dioxide is another one that's an emission

that's very dangerous. Coal frequently has sulfur in it, and when sulfur reacts with oxygen during the coal burning process, because again you need to have that oxygen to have combustion happen, you end up getting sulfur oxide, and that sulfur oxide can combine with other molecules. These emissions are harmful to us. Also, sulfur dioxide, once it has reacted fully, it's got a strong link to acid rain, so that's terrible also to smog and can be linked to problems

like bronchitis and asthma. Then you also have nitrogen oxides. It's another byproduct that it can also contribute to smog, and it also can end up leading to the development of respiratory ailments or make existing respiratory ailments much much worse. These are just a sample of some of the pollutants that can come out of burning coal. You also get coal ash. Uh. These are also called coal combustion residuals or CCRs, and this is actually again a collection of stuff.

It's not just one thing. Um. There's fly ash, which is mostly made of silica, which is powdery and very very fine. There's bottom ash, which is made up of large, coarse ash particles. These particles are too large for heat to carry them up the smoke stack of power plants, so they tend to gather at the bottom of furnaces.

There are some types of furnaces that create molten ash, also called boiler slag, which has to be drained or drawn out of furnaces regularly using a tap, and typically you would cool this mixture with water and at that point the ash turns into glassy pellets. And then there's the flu gas desulfurization material, which is a byproduct produced by a sulfur dioxide emission reduction process. It's typically either a dry, powdered material or a wet sludge, depending upon

the reduction method employed. I'll talk more about that in our next section. Now, coal ash also contains dangerous stuff in it, like lead, cadmium, arsenic, and mercury, and for that reason, regulatory agencies like the e p A, the environment Environmental Protection Agency, maintain pretty strict rules about how power plants may dispose of coal ash to prevent contaminants

from polluting the environment. These regulations under more recent years have been scrutinized and somewhat cut back due to political maneuvers by people who are in the e p A who previously came from the coal and power utility industries. I'll talk more about that because one of the big challenges we have to look at isn't a technological challenge.

It's not a scientific challenge, it's a political challenge. So burning coal releases a lot of energy that's useful, but it also produces stuff that's harmful to us and to the environment. And coal is plentiful and cheap, so it makes it a very attractive energy source. It definitely has its downsides. The pollutants are undeniably bad, but the fuel source is easy to get, and that's one of the big reasons why it's hard to wean ourselves off of

coal that's cheap and other options are less cheap. So how do experts propose to mitigate the pollution problems? In the next section, we're going to take a look at what clean coal is and how it works and try to answer the question how clean is it really? But first, let's take a quick break to thank our sponsor. All right, let's get this out of the way first. Clean coal

refers to processes and technology, not to coal itself. The coal used in clean coal applications is just as dirty as coal thrown into an otherwise unremarkable blast furnace, and coal is the dirtiest of fossil fuels, meaning that it produces more pollution and a wider variety of pollutants per unit burn than any other fossil fuel. However, the fact that coal is plentiful and inexpensive means it's likely to remain important in major industries like generating electricity for quite

some time unless something major changes. So engineers have dedicated a lot of time, research, and effort into creating systems that can limit the amount of pollution emitted into the environment. There are procedures that can reduce some of the stuff that would otherwise be released when you burn coal. And this is another important point. There's no single process that is good for reducing all pollutants. There's no one system that we can put coal through and get clean air

coming out of the smoke stack. On the other side, there are lots of individual systems that are really effective or pretty effective at reducing one or more of the pollutants, but there's no single approach that gets everything. So if you wanted to burn coal with a bare minimum environmental impact, you would have to employ multiple methods and thus have a more complicated system. And we'll talk a little bit more and a bit about why that's a big challenge. Now.

One of the methods you could use to have a clean coal application is called coal washing, and it's pretty much what it sounds like. There are two main approaches you can take. One involves a physical process in which you rely upon the different densities of the various contaminants found in coal to be able to separate them out and remove them and leave the coal behind. The other

relies upon chemical processes to remove those same contaminants. The most common of the two is the physical approach, not the chemical approach. Chemical approach is still one of those things that's constantly being studied, but so far, as far as I can tell, has not been scaled up to a degree where it could actually be used practically in

widespread applications. So with coal washing, with the physical approach, you take the raw coal that you've mined out of the ground, and then you use some heavy machinery to crush it up into much smaller pieces. You sift the crushed coal and you separate it into different sized particles um and you can use a series of sieves this way right. You can use one that's very fine, and

that way only the smallest particles come through. And once you've got all those out, you transfer the material to a sieve that has slightly larger grids in it, so that way slightly larger particles can come through. You do this several times until you've divided up the coal particles into different piles, and then you put them through their respective cleaning processes. The process is pretty much the same

for each one. It just it makes it easier to divide them up, so they all tend to work essentially the same way. You put the coal particles into a container like a vat, and it has jets water jets in it that can push water up through the coal, and it creates this upward current. The coal is lighter than the contaminants, so the coal gets pushed towards the top the contaminants to sink towards the bottom and you

can then separate out the coal from the contaminants. This way, then you have to dry the coal before you can use as a fuel. That's a process takes quite a bit of time and energy in itself. Uh. It reduces but does not eliminate all pollutants. So you could reduce, however, you know the amount of pollutants you're releasing into the atmosphere, but you don't eliminate them entirely, and it requires energy

to do this system. That's something that we also have to keep in mind in each of these steps is that the whole purpose of using coal in the first place is to generate electricity, at least in the applications I'm talking about here. But if you have to dedicate energy towards the process, that means you're you're eating into

your own returns. Right. If your goal is to create electricity and you're having to use some energy in your process, more and more of the energy and your process to get acceptable to generate electricity in this way, then you're eating into your own ability to generate the thing you're selling. You're you're eating into your own revenue, if you like. So. Another process focuses on the gas generated from burning coal.

Using what are called wet scrubbers, you can treat that gas so that a chemical reaction renders otherwise harmful emissions inert This is what I was talking about a little bit earlier in the last section. So sulfur dioxide, which can react with other gases in the atmosphere and create fine particles that are harmful to the environment and to the health of humans, is a great example. Sulfur dioxide

scrubber is a flu gas desulfurization technology. As the gases from burning coal moves from the furnace into a special chamber, nozzles spray a slurry made up of limestone and water. Limestone has calcium in it, and the calcium in the limestone reacts chemically with the sulfur dioxide. The main byproduct is a substance called calcium sulfate. You have this chemical reaction and you get calcium sulfate as a result, also

known as synthetic gypsum. This stuff can be used in other materials, including cement, so you can actually put it to use elsewhere, which helps bring down the cost. Right if you can, if you can put a byproduct to use it brings down the overall cost of the process because you recapture some of that by repurposing the material. Discrubbers can move a lot, but not all, of the sulfur dioxide emissions from coal firing plants if they are

properly used. Nitrogen Oxides are another problem, and they require a different approach. Nitrogen Oxides are a group of highly reactive gases that are poisonous. Coal combustion produces fuel nitrogen oxide and thermal nitrogen oxide. Nitrogen can't be removed ahead of time from coal, so the only options you have to come up with are away to remove it during or following combustion. You can't do a pre combustion cleaning to remove nitrogen. You can only do it as you're

burning it or after you've burned it during combustion. You could use what is called a low nitrogen oxide burner. This actually requires careful management of the ratio of fuel to air to reduce the amount of nitrogen oxide emissions during several stages of combustion, so it slows down this process. It's possible to retrofit existing boilers with these types of burners,

but they're limited in their effectiveness. They can reduce emissions between thirty to which is not bad, but it still means that you have almost you can have up to more than half of all emissions still going out into the environment, which is not great. After combustion, you can use something like selective catalytic reduction, in which you inject ammonia into a catalytic reactor and you can use something like titanium oxide as a catalyst as flu gas flows

through it. This is the gas given off by combusting. The Colt's very hot and it's got all these chemicals in it. All. The reaction with the catalyst and with the ammonia creates some byproducts like water, vapor, and nitrogen, not nitrogen oxide, but just nitrogen. This process reduces nitrogen oxide emissions by eight to nine though unreacted ammonia ammonia that did not actually go through this chemical reaction can

also become an emission that's not great. There's a similar approach called the selective non catalytic reduction that requires a higher operating temperature because you're not using a catalyst, which you know, catalysts make chemical reactions easier if you like. They facilitate chemical reactions well in the absence of a catalyst, you have to compensate by increasing the temperature um But then you don't have of a catalyst, and instead of

using ammonia, use a different chemical. The reaction with the fluid gas results in nitrogen, water, vapor, and carbon dioxide. The overall reduction of nitrogen oxide emissions tends to be between seventy four. But then you also have CEO two, which we'll get to a little bit later. Then there's the particulate matter that gets carried up in smoke stacks, the the coal ash, if you will, and can contribute

to stuff like asthma and other respiratory problems. One way to reduce those emissions is to use an electrical field or a series of high voltage electrical fields. The purpose of this is to impart an electrical charge onto the particulate matter as it moves through the system. Now, once those particles are charged, they will move near collection plates that carry the opposite charge, and opposite charges attract, so

the particular dust will cling to the collection plates. They can be really effective in removing that particulate matter, like percent effective in some cases. However, this also means using some of the electricity you're generating to power the system, so again you're getting a reduced return on your investment because you have to use some of that electricity just to keep the process from being too dirty. Another method involves a different approach to using coal called gasification, which

gives you a hint at what's involved. Use steam and pressurized air or pressurized oxygen, and you have that air oxygen heated too very high temperatures, and you combine all this with the coal. This forces a chemical reaction in which carbon molecules break apart and produce sin gas. That's synthetic natural gas I talked about earlier. Sin gas is a mixture of hydrogen and carbon monoxide. You also get water, vapor,

and carbon dioxide from this process. The sin gas, once chemically scrubbed, can be used in a gas turbine to generate electricity. So instead of generating heat to boil water and turn a steam turb line, you can have a a sin gas powered turbine that just takes the fuel

and uses that to generate electricity directly. Not only that, but then you can also capture waste heat from this process to boil water and turn a second turbine a steam turbine, so it can increase the the efficiency of a power system this way, and um, you essentially turn waste heat into productive heat. You still produce carbon dioxide this way, and that's a greenhouse gas, and that's still

a big problem. Uh. And carbon dioxide emissions continue to contribute to climate change, so reducing them is critically important to limit the damage we face in the years to come. Not to avoid the damage that's going to happen one way or the other, but to mitigate it. We need to cut back on carbon dioxide emissions in order to have that happen. So in the next section, I'm going to talk about carbon capture and storage, and then we'll wrap up the whole clean coal conversation. But first let's

take another quick break to thank our sponsor. Carbon dioxide makes up the vast majority, percentage wise, of all greenhouse gas emissions. Back in it was of all greenhouse gases emitted by man. Now, there's a natural process on our planet in which carbon gets removed from the atmosphere. Plants

do it as part of their normal life cycle. They take in carbon dioxide, but we're dumping way more c O two into the air than plants can absorb, and on top of that, we tend to wipe out large areas of plant life in order to do stuff like build cities or have farmland. The carbon we're introducing into the atmosphere has been locked away in coal for millions

of years until suddenly unleashed and dumped in there. So is there some way we could reverse that right and take carbon out of the air and lock it back up. The answer is not only yes, but also that there are lots of different ways we can do this. There are three general approaches when it. We're talking about coal power plants in particular, because there's no simple way of

just grabbing carbon dioxide from the atmosphere in general. So if we look at the places where we're dumping a lot of c O two and say, can we find a way to capture it right there at that source, that would be very helpful. So first, you can use sorbents or solvents to capture c O two. Adds orbins such as activated carbon or zeolites can separate c O two from other gas mixtures, and it's used in the

process of hydrogen production. It's also used to remove c O two from natural gas, but when it comes to coal power plants, that's a different story. Absorbent materials have a limited capacity to take out CEO two, and they aren't quite up to the task of doing the job on so large a scale as on flu gas. So while it does work in smaller applications for things like

a cold power plant, this approach would not work. Solvents are more promising, and in fact are actually being used in some carbon capture facilities already right now as the primary way of capturing carbon dioxide. UH there's a process called amine scrubbing in which derivatives of ammonia called amines, react with flu gas. They can potentially remove an enormous amount of carbon dioxide, practically all of it at least

on paper. But there are some questions about how quickly certain amines may degrade in flu gas, or how much energy is needed to regenerate the system. You know, how much do you how much energy do you need to put in to put in enough of the solvent the solvents to take out the CEO too, And without answering those questions, we can't really know if this is an effective approach on a large scale. But there are a lot of pilot programs out there that are using this method.

The next big way, because that was one, right, the sword bids and the solvents, The second big way to remove CEO two from gases is to use gas separation membranes, which is pretty much what sounds like. You can think of it again kind of like a sieve um. They allow certain materials to pass through and they keep other

materials back. And there are lots of different types of membranes out there, so I'm not going to go through them all because they get real technical and there are tons of them, but you would typically need several membranes along an entire stream because they don't individually achieve a high degree of separation. In other words, stuff can get through one membrane, so you want to have extra layers kind of extra layers of protection to capture all of

the CEO two. However, adding membranes adds complexity to the system, and complexity tends to translate into cost. It means, the more complex system, the more expensive it tends to be. You would likely need different types of membranes, not all just the same one. Because of the various byproducts that come from coal, combustion, and in any case, the membrane approach isn't currently scalable to be an effective, efficient and

affordable process for something like a coal power plant. So maybe one day it will be, but right now it isn't. It's still in the sort of research and development phase. The third big process is another one that's not going to work too well for major coal power plants, but it's cryogenic approaches. That means using the processes of cooling

and condensation to separate carbon dioxide from other flu gases. Again, it wouldn't be an effective process for post combustion treatment because you have to do a lot of other stuff to the gases first, like you would have to separate out the water vapor before you could use a cryogenic approach. You could use it in a pre combustion process, so

before you've actually um started to combust the coal. Capturing the CEO two, however, is just the first step after preventing the carbon dioxide from going into the atmosphere at large. Now you gotta do something with it, right, You captured it all, you put it into canisters. Now what Well, there are two main long term storage options. One involves burying the CEO two deep in the earth. I mean literally pumping it there. That's where we got the carbon

from from the first place. After all, right, we went down, we dug out coal, We burned the coal that released the CEO two. So in a way, we're just putting it back where it blocks, if you think of it that way. The other option is putting it into the ocean. We call these two approaches the geologic and the oceanic

carbon capture strategies. So with the geologic approach, you inject carbon dioxide deep into the earth itself, typically into underground oil or gas fields, where it can get absorbed in the into the ground, or you can actually pump it into any part of the earth that happens to have some salty water and poorous rock in the mix, and the carbon dioxide will soak in. The idea is that it will lock into the ground and stay there and slowly bind with the materials in the surrounding rocks over

the course of millions of years. The oceanic approach requires another step. First, you take the c O two you've captured, and then you have to pressurize it to get it down to the super critical liquid states. So now you've got liquid CEO two. This, by the way, is another energy hungry process and one that becomes less efficient as you scale up the system. You have to pour energy into it in order for it to happen, which again eats into your bottom line. Anyway, now you've got liquid

carbon dioxide. You inject the liquid c O two into deep water, and by deep, I'm talking about between five hundred and three thousand meters, which is around feet to just under ten thousand feet deep. At that depth, the waters pressure, the amount of water pressure is enough to dissolve the CEO two into the water. However, this process would in turn lower the pH of the water at that region, turning it slightly acidic, which could end up

being harmful to aquatic life. So this is something that we're not entirely sure would have a net positive environmental impact. Now keep in mind, to truly be clean coal, you would have to use multiple strategies I've talked about on this episode in order to get all the pollutants. Carbon capture is not going to do you any good for things like stopping mercury from getting out into the environment.

And even then, you're talking about reducing some of those pollutants significantly, but not eliminating them, so some of it's still getting out into the environment. And as you add in these various systems, as I mentioned earlier, it creates more and more complex facilities, and the more complex a

facility is, the more expensive it gets. Maintenance is also an added expense, so you end up with a system where the will is still cheap, the fuel is cheap and plentiful, but using it gets more and more expensive, especially if you want to use it in a way where you're capturing as many of these pollutings as possible.

Some of that expense also, like I said, it means dedicating some of the energy or some of the electricity in the in the system just to keep the whole thing running, So you lose out on some of the stuff you would otherwise sell to the public. And in order to stay profitable that might mean that you have

to raise the cost of electricity of the service. So as a general rule, and again this is this goes without saying that I'm gonna say it, companies aren't terribly keen on increasing costs and eating into the bottom line. That's generally thought of as a bad thing in business.

You want to cut costs and maximize profits. So the coal industry and power utilities in in the United States have lobbied historically to great extents and vigorously to limit regulations and in more recent years to reverse previously established regulations. And that's because clean coal, if implemented properly at scale,

is gonna be expensive. It is more environmentally conscious, It is the better choice to make from a health perspective, from an environment perspective, and I would argue from a long term economic perspective, but from a short term economic perspective, it may not be the most attractive option if you're

just looking at literally a return on investment. Shareholders want to see money come back to them when they pour it into an industry or a company, So it's hard to make that case to say in the short term, we are not going to see big returns, but further down the road, we're going to see much better returns, and we're also going to avoid doing further critical damage to the environment. Now, when I say that a coal power plant that's running on a clean coal strategy is

more expensive, what does that mean. It means that it costs about more to operate a clean coal coal plant than a normal coal plant. That's a tall order. Now, the cost of clean coal might make it less attractive than say, greener renewable energy sources, and you might say, oh, well, instead of doing this clean coal approach, maybe we should invest more in wind power or hydro power or solar power. A carbon tax, which is a tax in which companies would have to pay a fee in return for being

allowed to emit carbon dioxide. Sometimes there's like a credit program. You purchase credits, and for each credit, you're allowed a certain amount of CEO two emissions, but you have to pay for it. The idea is that this creates the incentive for companies to not emit carbon, to cut back on carbon emissions so as to avoid having to pay those fees. It's the idea of creating an economic system of pressure to force companies, or at least to encourage

companies to cut carbon emissions. That that could also help. And it would be really nice to see a move toward more renewable methods. If companies said, well, coal itself is still cheap, it's still easy to get, but using it as too expensive. I would love to see that because I would love to see more money going into renewable energy sources, which have a much lower environmental impact than coal or even natural gas, because again coal is the dirtiest fossil fuel. It's not hard to have a

lower environmental impact than burning coal. Uh And and also I shouldn't mention renewable energy sources still have an environmental impact. You know, we can't just say that they're magical and they don't harm the environment at all. That's not entirely true. You have to if you look at the big picture at how these things are made, there's still an environmental cost to be paid. It's just not nearly as dear

a cost as using coal. So one of the really big challenges facing renewable energy is that it's up against

a super cheap fossil fuel. If we decide the only way we can allow coal combustion is if we require coal plants to reduce emissions as much as possible, then it might become financially viable for more companies to invest in alternatives, because getting a coal plant up to speed incorporating all these systems might be more expensive than just scrapping it and saying all right, we're gonna get into

solar now. Um, so that's that's actually something that is possible if the regulations are put in place, But that has not been the trend, at least in the United States over the last couple of years. The trend has actually been in the reverse, getting rid of regulations as opposed to strengthening them. Now, some people could argue that advocating for clean coal at all is really a smoke screen pun intended to keep the status quo for as

long as possible. In other words, someone who says no, no, no, we need to keep investing in clean coal might really be saying I want to be able to keep using coal as a fuel source, and if I can argue that the research and development into clean coal is going to pay off and dividends, I can keep using coal. In the meantime, it becomes like a shell game. Uh.

Some clean coal technologies are mature technologies. They are proven and they can be used right now, and they are used and widely some of them, but others are still young, they're still in development. There's still questions about whether or not they can actually work on large scale applications. So the meantime, there are a lot of coal power plants out there with few of those systems in place, and they're dumping more CEO two and other pollutants into the atmosphere.

There are a lot of environmental advocates who say we can't continue with this, that we can't argue for clean coal and simultaneously not use the techniques that we already have created to mitigate coal's pollution. So it's a pretty dirty argument. Ultimately, clean coal the combustion of coal in a way that has the minimal environmental impact. I believe that is going to be possible with the right investments.

Whether those right investments are ever fully made and implemented is another question, because it may turn out that companies make this decision that it makes more sense to switch to a different energy source than it does to update all of these old power plants and have them run

under this new system. I worry right now that some of those advocates are absolutely right that clean coal is really just allowing an excuse to stick with an old, dirty fossil fuel that is doing more harm than good rather than and and pulling our focus away from alternatives

that could be much more beneficial. The nice thing I can say is that over the last few years, natural gas production has been on the rise, and natural gas, while still a fossil fuel, produces fewer pollutants than cold does, so the d emphasis on coal is a good thing. The problem is we need to make much more drastic cuts in greenhouse gas emissions than just switching from coal

to natural gas will allow. We have to go further than that, and the question is do we have the willpower and the ingenuity and the innovation necessary to do it. I think we do have the ingenuity and innovation. It's the willpower part that I question. Um. I certainly hope we do, because I would love to see a world where we are able to move off of fossil fuels entirely. I think it would improve not just the environment, but it could improve the economy. It could certainly improve things

like national security. If you are able to be self sufficient for your power needs entirely and you're not having to import fossil fuels, that's fantastic. It's a great way to improve national security. There are a lot of good arguments for it, but economically it maybe a harder sell, And sometimes that's the toughest battle to fight, is the battle of the price tag. What do you guys think. I'm curious to hear your thoughts about energy and what we should be turning to? UM, what should we really

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