Can clean energy replace fossil fuels?

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The discussion centers on the feasibility of clean energy replacing fossil fuels, with varying opinions on the technical and political aspects involved. While some argue that transitioning to clean energy for electricity is technically possible, significant challenges remain for other sectors, particularly transportation. The conversation highlights that achieving a complete shift to clean energy may take decades, and questions whether society has the time to make this transition. Concerns are raised about the economic implications and potential societal impacts of moving away from fossil fuels too quickly. Ultimately, the debate underscores that the issue is not purely technical but deeply intertwined with political priorities and economic realities.
  • #31
russ_watters said:
In the context of climate change, we don't have time to wait for running out of fossil fuels. We have to leave them in the ground, unused.
This assumes that we agree on fighting climate change. I do not see that. And even if we do, it would require a form of compensation to switch from cheap to expensive energy which I do not see either. And if you argue, that cheap fossil fuel plus climate change exceeds the costs of clean energy by far, then my argument is, that we have different costs objects and hence different interests, which again will block progress.

All these involve political decisions, not physical ones. A physical subject would be the availability of lithium, copper and iron. Phosphor is interesting, too, but a different debate.
 
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  • #32
f95toli said:
Sorry, no. I remember reading a bit about it when Virgin Atlantic flew their demonstrator a couple of years ago.
You get quite a few hits if you search for "jet fuel from biomass". As far as I understand they typically start with making ethanol, i.e. the "bio" bit is not very radical.
Fair enough, I'll probably look into it.

Also, the framing of the OP seems to have excluded financial considerations, but that's tough to do if a technology is really expensive. At some level the technological and financial challenges overlap (you hope technology can find a cheaper solution). One of the reasons I focus so much on electricity is that the financial constraints are practically nonexistent for carbon-free electricity, so we really should be able to choose to just do it. That we don't, is telling to me that people don't really believe climate change is a big problem. And if we won't even do it for electricity, replacing oil in transportation isn't a question that is really even on the world's radar.
 
  • #33
russ_watters said:
That we don't, is telling to me that people don't really believe climate change is a big problem.
It is. The question is to whom!
 
  • #34
fresh_42 said:
It is. The question is to whom!
At the very least we can say it has been declared so by basically every government on the planet, by signing the Paris Agreement:
"Recognizing the need for an effective and progressive response to the urgent threat of climate change on the basis of the best available scientific knowledge..."

But few if any are taking steps that are commensurate with the declared importance of the problem. The irony of the location that gives the treaty its title should not be lost: in 1973, the Prime Minister of France decided it was in France's financial interest to rid his electric grid of foreign oil. So he basically snapped his fingers/stroked a pen, and it happened (they did stop a bit short, but not much). It was really easy to do.

[edit] The OP seems to be spun/constrained to generate a technical answer "no" to support a conclusion of "since it isn't possible to totally get off fossil fuels, we shouldn't even bother trying at all." But that isn't the prevailing technical framing and view of the issue. The prevailing view/framing is that is *is* possible to make a radical impact on the problem. And not just "possible" -- it should be easy.
 
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  • #35
russ_watters said:
"since it isn't possible to totally get off fossil fuels, we shouldn't even bother trying at all."
Well, this is definitely wrong. But the way to do so, and this is what I wanted to say, always inevitably ends up in a political discussion, because the transition costs, and the fact that different states have to give up different levels of luxury must be addressed. The current distribution of costs and cost objects will not work. And I see nobody dares to speak it out loudly, with little exceptions like Germany and nuclear power. My remark on the costs of pepper was only half way funny. It summarized the problem.

To discuss it on a pure scientific, non political level is in my mind only possible as fas as lithium and copper resources are involved, and even this is political.
 
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  • #36
fresh_42 said:
Well, this is definitely wrong. But the way to do so, and this is what I wanted to say, always inevitably ends up in a political discussion, because the transition costs, and the fact that different states have to give up different levels of luxury must be addressed.
Yes. For us, here, we need to make sure the technical issue is properly framed and answered. After that it is up to the politicians to answer to their constituents the question of why it it hasn't happened.
The current distribution of costs and cost objects will not work. And I see nobody dares to speak it out loudly, with little exceptions like Germany and nuclear power.
I'm not quite clear on what you are saying there. What is this "distribution of costs and costs objects" issue?

Germany has one of the more aggressive current "energy change" programs, but oddly they have effectively declared that the greatest threat to humanity that needs to be addressed is nuclear power, not climate change.
 
  • #37
russ_watters said:
I'm not quite clear on what you are saying there. What is this "distribution of costs and costs objects" issue?
We say cost carrier, which Wikipedia translated to cost objects. People affected by climate change is a very different set of people who are asked to pay for it. In other words: the profits of coal and oil aren't balanced against its costs.
russ_watters said:
Germany has one of the more aggressive current "energy change" programs, but oddly they have effectively declared that the greatest threat to humanity that needs to be addressed is nuclear power, not climate change.
Theoretically, they try to deal with both. It isn't considered an either or. They will see when transportation and heating goes green on a large scale. The other energy consumers can probably be handled.
 
  • #38
Stopping the burning of fossil sources does not seem possible in the short term. Another possibility is to increase the absorption of CO2 on a large scale. This can be done by replanting Earth's great deserts, such as the Sahara. This would require a great effort, especially from the West, similar to the Apollo program to put a person on the moon. However, replanting of the Sahara can have a negative effect on the vegetation of the Amazon. See:

https://www.wired.com/2015/02/sahara-keeps-amazon-green/

A positive effect could also be that it creates employment in the areas concerned and can thus stop the ongoing migration to the north. But the Sahara is not the only desert in the world. Australia has a large desert area and also the US. Will be continued ...
 
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  • #39
Why do you want to plant in the deserts - one of the few environments where nothing will grow without massive energy expenditures - and not in places where it's actually viable?
You are proposing an alternative to cutting emissions. Something that is (rightly or not) deemed too costly, slow to implement, technologically infeasible, and politically unattractive. So don't go around proposing a solution that increases emissions, is costly, slow to implement, technologically infeasible, and politically unattractive.

Also, reforestation is a stop-gap solution. A mitigating action that can at best buy some time. So it's not an actual alternative to cutting emissions.
 
  • #40
fresh_42 said:
We say cost carrier, which Wikipedia translated to cost objects. People affected by climate change is a very different set of people who are asked to pay for it. In other words: the profits of coal and oil aren't balanced against its costs.
I guess I'm still really not following. It's well known and discussed that the people who profit from fossil fuels are not the same people that are harmed by them. Reconciling that sort of issue is one of the primary functions of government, and isn't a particularly difficult one in this case. Or, rather, the challenge is always political will. From a technical and economic standpoint, substantially reducing the carbon footprint of developed nations is easy.

Theoretically, they try to deal with both. It isn't considered an either or. They will see when transportation and heating goes green on a large scale. The other energy consumers can probably be handled.
Both ultimately yes, but nuclear power is the threat addressed first, more completely and pre-emptively. They aren't independent/parallel efforts; the nuclear power phase-out directly undermines the fossil fuel phase-out. So in judging based on the action taken, that makes the nuclear phase-out the much more important goal.
 
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  • #41
russ_watters said:
I guess I'm still really not following.
It is quite easy. People equipped with large amounts of capital invest in and profit from technologies, while the costs of these enterprises are carried by communities. This is the case with fossil fuels as it is with nuclear power. This is how our economies work. Any attempts to change this failed greatly. Hence we cannot change the role of capital. This means, however, that community costs (drowning islands, polluted air, severity of natural disasters, deposit of nuclear waste etc.) will not be redistributed to the capital used to produce them. This is a pessimistic outlook, I admit. As I see it, we are currently attempting to solve a planetary problem which affects us all by means which only applies to few. And as long as the few have no active interests in taking action, there will be no change. Economic inertia if you like.
 
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  • #42
fresh_42 said:
It is quite easy. People equipped with large amounts of capital invest in and profit from technologies, while the costs of these enterprises are carried by communities. This is the case with fossil fuels as it is with nuclear power. This is how our economies work. Any attempts to change this failed greatly. Hence we cannot change the role of capital. This means, however, that community costs (drowning islands, polluted air, severity of natural disasters, deposit of nuclear waste etc.) will not be redistributed to the capital used to produce them. This is a pessimistic outlook, I admit. As I see it, we are currently attempting to solve a planetary problem which affects us all by means which only applies to few. And as long as the few have no active interests in taking action, there will be no change. Economic inertia if you like.
Ok, fair enough. I just don't see/agree that this is a a real/relevant problem because governments can and do simply make what they want happen by decree. You don't necessarily need to change the entire structure of the market, and then hope it moves the way you want. They can just ignore it and do something different. That's what the government of France did. They didn't try to manipulate a market to favor nuclear power, they simply went and built a bunch of nuclear plants themselves. And on the other side, shutting down companies/markets by government fiat (nuclear and coal) is even easier.
 
  • #43
Rive said:
Since we are able to synthesize a good replacement for almost every fuel and plastic out from 'thin air' (a bit of an exaggeration here) with only energy, in theory it is 'possible' to switch to clean energy.
Oh, that sounds interesting. Do you have a reference for that?
 
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  • #44
Dale said:
Oh, that sounds interesting. Do you have a reference for that?
reference
 
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  • #46
  • #47
russ_watters said:
The framing of the issue by the OP might be weak, but it is the current mainstream view that climate change is the greatest threat to humanity we have now and maybe have ever had. So the issue of how to get away from fossil fuels is really, really important. I didn't think you disagreed with that.
I cannot say how much I agree with you and thank you for saying this.
russ_watters said:
In the context of climate change, we don't have time to wait for running out of fossil fuels. We have to leave them in the ground, unused.
If there is a possibility to neutralize CO2 emissions directly with the emissions, we might still be able to continue to use fossil fuels.
 
  • #48
How about CO2ube. Does it work or is it another fake?
 
  • #49
Ad VanderVen said:
How about CO2ube. Does it work or is it another fake?
So you fill your tank with gasoline. Say 20 gallons -- 150 pounds or so. A bit over 80 percent of that weight is carbon. You burn it and bind a couple oxygen atoms with each carbon. Roughly speaking, you've tripled the mass of the original gasoline and emitted that as CO2.

But you pop this device on your tailpipe and it magically absorbs most of the CO2 coming out of your tailpipe for a couple of months before you have to change out the cartridge...

That must be one honking big cartridge. Or a heaping helping of snake oil.

I suppose though, if this device could provide enough energy to separate the CO2 into carbon and oxygen and dribble a 130 pound trail of diamonds on the highway as you drive a couple of hundred miles, that could work.
 
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  • #50
Its not that difficult - wind and solar ger cheaper as production and infrastructure scales. They are currently the lowest cost source of new, utility-scale electricity generation. As PV cells are a semiconductor technology, we can expect the ‘moore’s law’ like exponential decline in cost that occurred over the past ten years to continue. This in a few years makes new solar cheaper than running existing coal, gas or nuclear plants.

For small vehicles, EVs or PHEVs likewise become cheaper as production scales. They are far simpler mechanically than IC engines and therefore can become significantly cheaper than traditional autos.

This leaves large vehicles, marine and air transport. Better battery technology, like the new glass batteries may enable some of this. Clean air transport may have to wait until there is enough surplus renewable power generation to create H2

grphx_lcoe-02-02.jpg


https://www.lazard.com/perspective/levelized-cost-of-energy-and-levelized-cost-of-storage-2020/
 
  • #51
BWV said:
Its not that difficult - wind and solar ger cheaper as production and infrastructure scales. They are currently the lowest cost source of new, utility-scale electricity generation. As PV cells are a semiconductor technology, we can expect the ‘moore’s law’ like exponential decline in cost that occurred over the past ten years to continue.
No, we really can't. Solar arrays are made primarily of structural steel, concrete and human labor. Also, large electrical switchgear, wires and regulators/inverters. Those things do not follow Moore's law.

And I don't even think the semiconductor nature of the panels has any relevance here. The underlying technology and its capabilities have changed very little over time. PC processors got cheaper because as the manufacturing technology advanced, the manufacturers could pack more circuits into the same size package without much more effort. Chips didn't primarily get cheaper, they "just" got faster. Solar panels haven't changed much at all in decades. What I think drove the cost down is primarily economy of production scale.

What’s happened to solar electricity costs is very orthodox economics: when a technology scales up, it becomes cheaper (this is known as Wright’s Law, and was formulated in 1936), which he summarises this way:

“Every doubling of cumulative production leads to a percentage change in cost.”
In the case of solar, the cost of the electricity produced declines “smoothly” in line with how much solar power is deployed.
https://www.solarquotes.com.au/blog/ramez-naam-solar-cost/

And as I frequently point out, the intermittency problem is real and it's big. And we're just getting to the point where enough solar has been implemented that it can't be ignored anymore. The "overbuilding" idea averages out to solar getting 4x more expensive on average, while the marginal cost rises exponentially. It can be done, but I think we're close to if not already past the point of solar getting cheaper and moving toward it getting more expensive.
 
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  • #52
russ_watters said:
No, we really can't. Solar arrays are made primarily of structural steel, concrete and human labor. Also, large electrical switchgear, wires and regulators/inverters. Those things do not follow Moore's law.

Fair enough, the analog to Moore is Swanson's Law, which is roughly a 20% decline in price for every doubling of shipped volume - as you note, this is about manufacturing efficiency, not transistors.

https://en.wikipedia.org/wiki/Swanson's_law

From what I could see, module costs are about 30% of total utility-scale installations, so a doubling in PV shipment would result in a 6% decline in total installation costs. This does not assume any efficiency gains, which have definite physical limits, but still could be meaningful. Importantly, installed costs of conventional energy are not declining and solar is already cheaper.

The intermittency issue is solved in the short term by combined cycle gas and in the long term by storage. A fully renewable grid would have to generate surplus power at peak sun and wind times that was then stored for later use.
 
  • #53
BWV said:
The intermittency issue is solved in the short term by combined cycle gas and in the long term by storage. A fully renewable grid would have to generate surplus power at peak sun and wind times that was then stored for later use.
Which should be included in the cost comparison, but often is neglected
 
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  • #54
Dale said:
Which should be included in the cost comparison, but often is neglected

Solar and wind intermittency tends to be negatively correlated (more wind at night, and less wind when it is hot and sunny). Geographic diversification also reduces the issue. TX is an entirely isolated power grid with 25% wind compared to the 7% national average and works just fine. it is a solvable engineering problem under active study, but not a real issue until renewables become a far larger percentage of total power generation.
 
  • #55
BWV said:
it is a solvable engineering problem under active study, but not a real issue until renewables become a far larger percentage of total power generation
I completely realize that it is a solvable issue, but the costs still need to be included in the analysis and often are not. Especially when we are talking about a complete replacement for fossil fuels
 
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  • #56
I used to work with a company that dealt with solar cells, but as far as their results suggest, solar cells are not yet a viable option for mass replacement of conventional energy sources.

Solar cell efficiency and lifespan is quite keen to environment compared to conventional energy sources. So everything becomes a balance of various factors. Many large scale solar cell grid tend to target desert near equator because high energy production per lifespan and cost tend to be realized. They have the most stable sunlight throughout the year and do not suffer from weather (because it's mostly sunny). At the same time, they will suffer from accumulated heat (reaches as high as 80 degrees Celsius) that lowers efficiency and also accelerates degradation. A typical solar cell have a lifespan of of 30 years, but this could quickly fall to 15 - 20 years in such environment until they need to be replaced. The company I used to work with stated that they will not sell any product that will fail to adequately maintain their efficiency for shorter than 20 years, which means they are willing to raise cost of production for higher durability. What I'm trying to say here is that a "typical lifespan" or "typical cost" doesn't explain well the scalability of energy sources that is keen to environment.

Meanwhile, things like nuclear energy (which I consider them to be a "clean energy") generates tremendous amount of energy. Constraints may be the fact they can only be built around the coast (main parts are too big that they have to be transported through ships), but they don't consume too much land and generates large amount of energy. I don't understand country like Germany (no offense to Germans here) and their hypocrisy in saying that they are going to eliminate nuclear power, while buying electricity from France that relies heavily on nuclear power. I also don't understand the irrational fear of nuclear power; it has killed one of the, if not, the least amount of people per unit energy production.

I know I'm not supposed to talk political here, but I can't imagine a situation where people can politically push through with the agenda of new sources of energy as a mass replacement of conventional energy and actually make it work, when they can't even accept nuclear energy as "clean energy" despite data suggesting that they are one of the cleanest and safest energy out there.
 
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  • #57
Dale said:
I completely realize that it is a solvable issue, but the costs still need to be included in the analysis and often are not. Especially when we are talking about a complete replacement for fossil fuels
I would add that vehicles that use fossil fuels have significantly increased their fuel consumption efficiency. And at least over here in Japan, hybrid cars have evolved from a luxury to a fairly mainstream option. You can buy new hybrid cars as low as 15k US$ here. That makes replacement options of fossil fuels to be even less attractive. So you are absolutely right that cost effectiveness is definitely something that needs to be included in the analysis, and that they should be done from both domains.

Furthermore, "clean energy" (most people's definition excludes nuclear energy, which I disagree) has been studied and engineered for several decades now but hasn't reached a point where they are truly a cost-viable option. Now you can make an argument that "clean energy" doesn't have the same span of time of development compared to fossil fuels so they are sure to eventually catch up, but it's hard to agree on something that has not been practically fully developed yet.
 
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