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Can You Make a Wind Turbine Without Fossil Fuels?

Wind Turbine and Energy Use

Various scenarios have been put forward showing that 100% renewable energy is achievable. Some of them even claim that we can move completely away from fossil fuels in only couple of decades. A world entirely without fossils might be desirable, but is it achievable?

The current feasibility of 100% renewable energy is easily tested by asking a simple question. Can you build a wind turbine without fossil fuels? If the machines that will deliver 100% renewable energy cannot be made without fossil fuels, then quite obviously we cannot get 100% renewable energy.

This is what a typical wind turbine looks like:

What is it made of? Lots of steel, concrete and advanced plastic. Material requirements of a modern wind turbine have been reviewed by the United States Geological Survey. On average 1 MW of wind capacity requires 103 tonnes of stainless steel, 402 tonnes of concrete, 6.8 tonnes of fiberglass, 3 tonnes of copper and 20 tonnes of cast iron. The elegant blades are made of fiberglass, the skyscraper sized tower of steel, and the base of concrete.

These requirements can be placed in context by considering how much we would need if we were to rapidly transition to 100% wind electricity over a 20 year period. Average global electricity demand is approximately 2.6 TW, therefore we need a total of around 10 TW of wind capacity to provide this electricity. So we would need about 50 million tonnes of steel, 200 million tonnes of concrete and 1.5 million tonnes of copper each year. These numbers sound high, but current global production of these materials is more than an order of magnitude higher than these requirements.

Fossil fuel requirements of cement and steel production

For the sake of brevity I will only consider whether this steel can be produced without fossil fuels, and whether the concrete can be made without the production of carbon dioxide. However I will note at the outset that the requirement for fiberglass means that a wind turbine cannot currently be made without the extraction of oil and natural gas, because fiberglass is without exception produced from petrochemicals.

Let’s begin with steel. How do we make most of our steel globally?

There are two methods: recycle old steel, or make steel from iron ore. The vast majority of steel is made using the latter method for the simple reason that there is nowhere near enough old steel lying around to be re-melted to meet global demand.

Here then is a quick summary of how we make steel. First we take iron ore out of the ground, leaving a landscape looking like this:

This is done using powerful machines that need high energy density fuels, i.e. diesel:

And the machines that do all of this work are almost made entirely of steel:

After mining, the iron ore will need to be transported to a steel mill. If the iron ore comes from Australia or Brazil then it most likely will have to be put on a large bulk carrier and transported to another country.

What powers these ships? A diesel engine. And they are big:

Simple engineering realities mean that shipping requires high energy dense fuels, universally diesel. Because of wind and solar energy’s intrinsic low power density putting solar panels, or perhaps a kite, on to one of these ships will not come close to meeting their energy requirements. We are likely stuck with diesel engines for generations.

We then convert this iron ore into steel. How is this done? There are only two widely used methods. The blast furnace or direct reduction routes, and these processes are fundamentally dependent on the provision of large amounts of coal or natural gas.

A modern blast furnace

The blast furnace route is used for the majority of steel production globally. Here coal is key. Iron ore is unusable, largely because it is mostly iron oxide. This must be purified by removing the oxygen, and we do this by reacting the iron ore with carbon monoxide produced using coke:

Fe2O3 + 3CO → 2Fe + 3CO2

Production of carbon dioxide therefore is not simply a result of the energy requirements of steel production, but of the chemical requirements of iron ore smelting.

This steel can then be used to produce the tower for a wind turbine, but as you can see, each major step of the production chain for what we call primary steel is dependent on fossil fuels.

By weight cement is the most widely used material globally. We now produce over 3.5 billion tonnes of the stuff each year, with the majority of it being produced and consumed in China. And one of the most important uses of cement is in concrete production.

Cement only makes up between 10 and 20% of concrete’s mass, depending on the specific concrete. However from an embodied energy and emissions point of view it makes up more than 80%. So, if we want to make emissions-free concrete we really need to figure out how to make emissions-free cement.

We make cement in a cement kiln, using a kiln fuel such as coal, natural gas, or quite often used tires. Provision of heat in cement production is an obvious source of greenhouse gases, and providing this heat with low carbon sources will face multiple challenges.

A modern cement kiln

These challenges may or may not be overcome, but here is a more challenging one. Approximately 50% of emissions from cement production come not from energy provision, but from chemical reactions in its production.

The key chemical reaction in cement production is the conversion of calcium carbonate (limestone) into calcium oxide (lime). The removal of carbon from calcium carbonate inevitably leads to the emission of carbon dioxide:

CaCO3 → CaO + CO2

These chemical realities will make total de-carbonisation of cement production extremely difficult.

Total cement production currently represents about 5% of global carbon dioxide emissions, to go with the almost 7% from iron and steel production. Not loose change.

In conclusion we obviously cannot build wind turbines on a large scale without fossil fuels.

Now, none of this is to argue against wind turbines, it is simply arguing against over-promising what can be achieved. It also should be pointed out that we cannot build a nuclear power plant, or any piece of large infrastrtucture for that matter, without concrete or steel. A future entirely without fossil fuels may be desirable, but currently it is not achievable. Expectations must be set accordingly.

Recommended Reading

Sustainable Materials With Both Eyes Open – Allwood and Cullen

Making the Modern World: Materials and Dematerialization – Vaclav Smil

Content Discussion

Robert Wilson's picture
Robert Wilson on February 28, 2014

Thomas

If you can show me a single mainstream turbine manufacturer who takes seriously the idea of using wood instead of steel in tower construction then you might have a point. Why would anyone wish to replace steel and concrete with wood? It is a poorer material in almost every sense, from a structural point of view. It also costs a lot more to provide the same service.

It’s also incredibly dubious that replacing steel with wood in construction is a better choice ecologically. How much deforestation do we need? Have you ever looked at the wood harvest statistics and compared them with global steel demand?

donough shanahan's picture
donough shanahan on February 28, 2014

Getting off topic but ethylene production is steam cracking of a hydrocarbon feed such as LPG, naphta, propane or ethane with ethane being by far the most cost effective. Ethane is sourced from natural gas. I would be unsure as to the economics of the route from syngas to ethane/ethylene.

The syngas route would be primarily using methane or coal as its feedstock. This route can produce ethylene but its focus is very much on fuels. However ethane is in short supply so that may provide a kickstart.

Thomas Gerke's picture
Thomas Gerke on February 28, 2014

Robert, 

your article asked the question “can we” so “are we right now” is not really the point of the article. So could we please stick to the topic.
 
“Timbertower” is a start-up that has build a working 100m prototype last year. It created alot of interesst. They are now working on a tower for a hub-height of 140m. 

I am sorry to say, but I don’t think that you have put alot of thought into your comment. Your case against wood in construction appears to be rather emotional and not fact/research based. Simply because we no longer commonly use wood for advanced construction methodes does not mean that it is an inferiour building material. 

Why would anyone wish to replace steel & concrete with wood?

“Wood” or wood composites have a variety of high grade technical properties that are superiour to steel/concrete depending on the given task. Wood is long lasting, has better fatigue performance, has a higher structural robustness / kg, is easy to recycle… and it’s a sustainable ressource we are actually  producing in a sustainable way in some places on an industrial scale. 

Advantages in the case of the Timbertower:
– the parts are lighter & easier to transport/assamble
– it’s actually cheaper than a steel tower
– the materials can be locally sourced (from sustainable forrestry)
– due to the operational lifetime and since it displaces carbon intensive materials in construction reduces emission and can function as a carbon sink
 
On de-forestation:
You do realize, that de-forestation is mainly caused by un-sustaibable agriculture, husbandry & overfelling… Correct me if I am wrong, but  (re-)introducing wood / biomass as long lasting ressources in construction & other materials is commonly known as part of the solution to our climate & ressource crisis, NOT the root cause.

donough shanahan's picture
donough shanahan on March 3, 2014

Thomas

Biocoke is certainly being researched and CSIRO is a leading name and suggests its immediate use for the anodes in an aluminium smelter. The Canadians are looking at replaceing injected coal with biocoke. An advantage of biocoke is the low sulphur and ashcontent. Biocoke has been used in shaft furances for waste metal processing which are no means small but not on the scale of the blast furnace. As of 2013, most people are at the earliest stagest of trialing this material in a blast furance. The big issue is the strength, CSR as ASTM stability and strength and biocoke falls badly on CSR. This is why it has been trialed in applications described above that do not require extremes in these measurements.

Thus it you who needs to do research and do it well.

http://www.kuettner.com/Files/Filer/Downloads/en/Kuettner_shaft-furnace.pdf

Steve Frazer's picture
Steve Frazer on February 28, 2014

The author is taking a somewhat uninformed position based on the options.  My firm has several divisions and wholly own subsidaries – including the engineering, manufacture and installation of wind turbines AND a Mining Division.  Granted, we are the poster child for mining (we have 67 mining claims today with 4 new acquisitions in the works) with our use of solar, wind turbines and biodiesel sourced from 2nd generation feedstocks and 97% recycled water with no use of holding ponds and no use of harsh chemicals.  It can be done and done profitably.

My point is simple – there are no longterm dependencies on fossil fuels for transportation or mining or the manufacture of renewable energy products – pure and simple. 

My firm is planting 2nd generation feedstock orchards on 4 contenients everyday and the volume of biodiesel that can be produced from these efforts will far exceed petroleum extraction within 2 decades.  We already use biodiesel in our heavy equipment, generators, heavy haul trucks, etc.  The rest of the world will catch up when the volume is available and the economics are motivating.  At $1/gallon for biodiesel production, that will be sooner than later.

Sincerely, we produce and sell 2nd generation feedstock sourced biodiesel simply because it is the only scalable, environmentally friendly, economically viable and truly sustainable replacement for petroleum available today.

Robert Wilson's picture
Robert Wilson on February 28, 2014

Thomas

As always engaging with you is fruitless. I express a view that reflects the mainstream opinion of materials scientists and those involved in wind turbine construction and you call it “emotional.”

Take a step outside of the silo you live in, it might do you some good.

Robert Wilson's picture
Robert Wilson on February 28, 2014

Steve

If you want to put forward low power density biofuels as a solution to climate change then you are welcome to try. But tell me, where is the land to grow the feedstock for this “scalable, environmental friendly” and “truly sustainable” replacement for petroleum?

Low power density of biodiesel means it is delusional to believe they can replace petroleum on a big scale. They will instead promote starvation by displacing food crops, and environmental destruction through de-forestation. Is this what you want? Or have you just not thought about it too much?

Max Kennedy's picture
Max Kennedy on February 28, 2014

Unfortunately the question asked in the title isn’t even addressed in the body of the text, which simply looks at how things are done now.  I’ll give just 1 example of how this article fails in every respect, the shovel used to dig out the ore isn’t deisel but deisel-electric.  The deisel only provides the electricity needed to motivate the electric motors in the shovel, replace that with an electric cable, no deisel.  PITA yes but readily do-able.  Similar examples of non-petroleum based alternatives are easily made for everything else.  this is not an article about “CAN WE” but a rationalisation of why we don’t!  Call a spade a spade.

Robert Wilson's picture
Robert Wilson on February 28, 2014

Max

This is just not true. Show me a readily available non-petroleum alternative to the two 32 MW engines that will power Maersk’s new container ship. Show me how you make a billion tonnes of steel each year without fossil fuels. These “readily do-able” alternatives may exist in the minds of some environmentalists, but they are a long way from engineering reality.

Max Kennedy's picture
Max Kennedy on February 28, 2014

It’s called sail, was around for hundreds of years and is under new development.  As I said a PITA but DO_ABLE!  Already an established engineering reality, couple hundred years ago at that.

Robert Wilson's picture
Robert Wilson on February 28, 2014

Max

I suggest you email Maersk with a suggestion to power their container ships with sail. It will provide some entertainment for an entry-level administrator within the company.

Nick Grealy's picture
Nick Grealy on February 28, 2014

Another proven renewable technology in the maritime transport sector is galley slaves.  But only ones powered by vegan diets.

Robert Wilson's picture
Robert Wilson on February 28, 2014

Oh come on Nick,

You can do much better. Does natural gas not offer us the chance to reduce emissions in the maritime sector? 

Max Kennedy's picture
Max Kennedy on February 28, 2014

The title was “CAN WE”, I suggest you look at all the possibilities.  Perhaps the title would have been better to say “Is it currently practical”.  Then looked at how we could get there.  This article isn’t about CAN but about rationalising how it is currently done.

Thomas Gerke's picture
Thomas Gerke on February 28, 2014

Robert, 

I also don’t get why you feel the urge to insult me, instead of discussing the things I added to the debate, which were completly on topic.

Being on topic is something that can not really be said about the second half of your post though. You article heading & introduction address the question “Can You Make a Wind Turbine Without Fossil Fuels?”. Unfortunatly you didn’t really investigate this question, instead you discussed how ressource intensive todays globalized industrial sector is. Something that everybody knows, which is the reason why we discuss alternatives & new ways to do stuff. 

If you read my comments carefully, you will notice that I did choose to address the original topic of your article by providing information on two possible solutions to reduce the fossil fuel/carbon footprint of a modern wind turbines signifcantly. 

Instead of looking into it, you said “wood sucks” (paraphrasing) on which I replied to you that it doesn’t. I actually added several advantages of wood for tower construction. Most importantly the higher structural robustness / kg of wood. Meaning it is significantly lighter while doing the same job. 

If you take offense in me calling your uneducated dismissal of wood as a modern construction material in the 21st century “emotional”, you should fact check your statements better in the future and engage the argument properly.

Robert Wilson's picture
Robert Wilson on February 28, 2014

As always Thomas, you state a fringe green point of view and seem to imagine it is mainstream, and then criticise me for stating a mainstream view among materials scientists. Most materials scientists do not believe that wood can replace steel for many purposes. You, evidently, don’t agree with that, but don’t go around calling such positions “emotional.”

And, yes, once again you insult me and then when I respond you complain about me insulting you. As I’ve seen before engaging with you is tiresome.

Nick Grealy's picture
Nick Grealy on February 28, 2014

But then I may be accused of being biased.  Unfortunate by product of cheaper and cleaner LNG ships and trains is lower freight cost for a major customer: Coal.

Robert Wilson's picture
Robert Wilson on February 28, 2014

Interesting. So you aren’t that sure LNG ships will promote your financial interests then. Swings and round abouts.

Thomas Gerke's picture
Thomas Gerke on February 28, 2014

Robert: Thanks for telling me what I think, I wasn’t aware of it.

How is introducing a novel enginieering solution that can reduce the carbon footprint of wind turbine construction to this debate, “imagining that a frindge green point of view is mainstream”?  

I never said that the reality of our global economy isn’t as challanging as you described it. 
However if mainstream opinions are the gold standard for discussing “The Energy Transition” we don’t really get very far. Because changing the energy / ressource landscape requires the introduction of new solutions. Can we agree on this at least?

Luckily the material science community doesn’t share your view on wood. Do some reasearch and you should be able to find that the (re-)discovery of wood is a very hot topic in many areas. For example we already know how to make PET out of wood or build wooden skyscrapers.

—-

I am sorry if you took offense by me using the word “emotional”. I wrote “ignorant” at first, because your statement of “wood being inferiour” lacked any factual basis, since it appears to be superiour in this application. I changed it to “emotional” because I guessed that you might be eager to dismiss anything I say. I also considered that conventional wisdom suggest that wood is an outdated/inferious material => thus you dissmissing it might just have been an emotional outburst.It’s a pity that it still ticked you off into rage mode, making you unable to discuss the topic of your own article… 

Robert Wilson's picture
Robert Wilson on February 28, 2014

This is just silly. I am “emotional” because I stated a view in line with the “conventional” view of materials scientists on whether steel is superior to wood. Do you realise how silly you are? Please think before you type.

Thomas Gerke's picture
Thomas Gerke on February 28, 2014

This is indeed silly, you keep avoiding discussing the topic and keep insisting that your personal opinion is some kind of common view shared by academia. 

In reality no serious material scientists would ever sign a blanket statement like “steel is superiour to wood”. He would properly ask “under which circumstances / for what application?” followed by an analysis.  

If you would ask a material scientists:
Is steel better suited  than wood for building a wind turbine tower for hub heights above 100m, he would however definatly tell you that a conventional steel tube tower would not be practical / prohibitvly expensive
It’s possible to build very high steel framework towers, but it’s my understanding that they are rather labor cost intensive. 

While wood has it’s own set of challenges it’s able to do the job, while sporting several ecological, logistical and economic advantages. This has been demonstrated by the award winning Timertower concept and their working prototype.  Will this concept become a success in the industry? I don’t know and time will tell. 

The construction of wind turbines with hub heights above 100m does not have a very long tradition. While steel reenforced concrete is the common solution right now, it is still abit early to dismiss new innovative ideas IMO. 

Some additional reading:
http://www.windpowerengineering.com/featured/business-news-projects/whats-holding-up-tower-technology/

Roger Arnold's picture
Roger Arnold on February 28, 2014

Taking it far too literally?  Perhaps.  Everyone carries a personal context with them that influences what they hear and see, and how they interpret it.  Can’t get away from that — it’s how our brains work.  The personal context that I bring to this dialog is one that has perhaps left me overly sensitive to claims that it is impossible to do this or that without fossil fuels.  I recall exchanges with followers of a particular energy story line.  

I won’t go into details, but the upshot of that story line is that fossil fuels are a precious and irreplaceable legacy from ancient sunlight, that our entire industrial civilization was made possible by and depends wholly on the richness of that legacy, and that once we have burned our way through it — as we are near to doing — what we know as civilization will collapse and humanity will follow the dinosaurs into extinction.  The followers of this story line really believe the thesis that it is impossible to build wind turbines — or solar panels or nuclear plants — without fossil fuels to power those activities.  They are happy to torture EROEI analyses until they surrender and agree to back their claims.  I really, really don’t like that.  And I can see the followers of that camp seizing on your article as one more “proof” that they’re right.

Regarding fuel synthesis, it isn’t necessary or reasonable for the production of synthetic fuels to ever reach the volume of current oil and gas production.  It only needs to supply enough for whatever would be difficult to electrify.  It certainly isn’t reasonable to look to it as the only or even the primary way to deal with CO2 emissions from coal and gas-fired power plants.  But there are credible estimates that the cost to produce synthetic fuel, given a source of cheap electricity, is close to the current cost of new oil. In fact there’s an existence proof: the George Olah renewable methanol plant in Iceland.  With access to Iceland’s cheap geothermal electricity, it produces methanol that competes comercially with methanol from natural gas.  

That’s why I bridled at your statement that it would be the work of generations “to make it work”.  That implies that fuel synthesis doesn’t work now, and that it’s such a difficult problem that it will require the work of generations to crack it.  But it already does work, from a technical perspective.  Deployment is an issue of economics and the cost of the conventional alternative.  Cheaper electricity and reductions in the capital cost of electrolysis could make it competitive with current oil prices, but it can also (and will) become competitive if oil prices simply rise much more.

Robert Wilson's picture
Robert Wilson on February 28, 2014

Cliff

Can you please use your real name? Asking people to respond to lengthy comments by anonymous people is a bit of an ask.

Robert Wilson's picture
Robert Wilson on February 28, 2014

Thomas

You seem to imagine that all of the world’s engineers are a bunch of fools who don’t know what the hell they are doing. Perhaps 300 years after Newcomen they will discover that the old techniques were better than what came with the Industrial Revolution.

As I have said before you clearly have an incredibly weak grounding in basic science, and should try to get one. Instead you continually attack me by making statements that fly in the face of the hard won understanding of nature given to us by a few hundred years of scientific research.

Whether it is you telling me wind turbines can generate more electricity than is physically impossible or your statement earlier about the structural qualities of wood versus steel, you continually make statements that flout the laws of physics. But instead of doing some work informing yourself you attack for me for being uninformed. Teaching you basic science is not something I have the time or the inclination to do. Not only this, you have repeatedly accused me of being a liar and of intentionally misleading people. Why? Because I do not agree with with your statements that just happen to disregard the laws of physics.

If you stop making statements that disgregard basic science then perhaps we can have a conversation, otherwise it just grows more and more tiresome.

Robert Wilson's picture
Robert Wilson on February 28, 2014

Durwood

Fertilizers are perhaps one of the world’s most productive uses of energy. About 1% of energy consumption goes towards this. Incredible productivity considering that current levels of human population quite probably could not be maintained without synthetic fertilizers.

EROI calculations are worth doing, but this is probably too involved for columns here. I try to keep things below 1,500 words. An EROI post would probably take up too much of my time that I could spend writing about other things.

Exactly what resources is the world peaking in? This seems to be as much a statement of faith to me as the one that economies. Every time someone tells me we are running out of something I find someone who is running into that thing.

Your point about scale is very valid. People almost never discuss the current scales of energy consumption. This leads to such dubious ideas as thinking that we can fully replace fossil fuels in two decades. These beliefs are understandable given the general unwillingness of journalists and other to report actual numbers. If quantitative discussion actually occured then perhaps more realistic expectations could be set.

 

Thomas Gerke's picture
Thomas Gerke on February 28, 2014

Sure Robert, 

me saying that changing circumstances in one sector (shipping) and overall technological progress can lead to rapid innovation when applied to new novel solutions, is calling engineers idiots? Right.

You do realize that re-envisioning existing concepts due to changing circumstances / available technologies is happening all the time. For example right now there is alot of buzz about the electric vehicle… not a new concept, but gas is expansive & we got these new alloys & batteries are improving.  

You should really try not to imagine too much and reply only to what you read.
(an advice I also try to uphold, after past misunderstandings)

———– 

You continue to be inmature by saying that I have a disregard for basic science, while you have failed to provide any justification for your claims against enginieered wood as a modern construction material. I guess all those material scientists & enginieers working in that area are just idiots for you…
Poor guys… didn’t get the memo from good old Robert W. about concrete & steel being THE ONLY proper building materials!

————–

I also fail to see how my statements on wind power violated physics….
If I remember correctly I said that wind turbines / farms can reach higher power / unit area values than discribed in the chart from David MacKays popular science book. You called this impossible and unscientific…. even after an empirical analysis by  David MacKays looking at a bunch of really old wind farms in the UK had some far exeeting tha W/m² area we argued about. 

Since then you have build your little story about me not understanding basic science, completly ignoring that improvements in the W/m² value of wind turbines are obviously possible because it’s a function depending mainly on two variables. The area ( spacing can differ / be optimized) and the average wind speed (which can differ from location & hub height). 

Paul O's picture
Paul O on February 28, 2014

Thomas, Concrete is very strong in compression, and it is reinforced with steel re-bars. This is standard engineering practice…No surprise, nothing new.

BUT If you are saying or implying that Wooden Towers can be used to displace Steel towers for use with Wind Turbines, I would have to demnd evidence from you.

Steel has a higher strength to weight / volume than wood. This is true of Tensile strength, Torsion, Shearing and/or compression.

There is a very good reason why Long span Bridges are built with steel and concrete, and why the forlks who put up wind turbines don’t use wood for the towers.

I am surprised that we are even debating this.

Robert Bernal's picture
Robert Bernal on February 28, 2014

Steel IS better than wood for building towers and bridges… Don’t believe that? Please search “structural properties steel” and the same with “wood”. I already know, because I can break a 2×2 cm piece of wood with my own two hands (or foot) but would NEVER try that with steel ! We build cars and skyscrapers out of steel for a reason… it is simply very much stronger.

Besides, we need to leave as many trees as possible, alone as per for nature and for sequestering excess CO2 (until our kids figure out the best way to remove it for good). Wood requires more maintenence because it expands and contracts, absorbs moisture, rots and invites termites. I thought about framing home built solar panels with it… but then realized that those aluminum frames are even much better.

Robert Bernal's picture
Robert Bernal on February 28, 2014

I do not believe that “bio-anything” could scale beyond even a tenth of declining oil. They are measured in per acre/year and do not generate power like gigawatt years. They can not power a 10 billion person strong, fully developed planetary civilization (but they can power a few million and keep up the good work, every bit helps!).

Thomas Gerke's picture
Thomas Gerke on March 1, 2014

Hi Paul,

there is no doubt, that steel & concrete have their clear advantages for many / most high performence construction tasks. But using them in construction also has its set of challenges. 

I just think it’s sad & silly to dismiss modern enginieering solutions using wood composite materieals as “green fringe idea” as Robert has done w/o looking into it.

Here are some links:
http://www.windpowerengineering.com/featured/business-news-projects/whats-holding-up-tower-technology/

http://www.timbertower.de/de/

http://www.energyawards.de/awards/die-finalisten-2013/timbertower/

Thomas Gerke's picture
Thomas Gerke on March 1, 2014

Look, I am not saying that wood is better for EVERYTHING.

Hower it’s just silly to ignore the challenges of using steel and turn it into some kind of super material.
As Robert has shown, steel & concrete are very carbon intensive. Both also faces material fatigue from wear & tear. For example if you bend a piece of steel again & again it will get stiffer and eventually just break. Using wood also has it’s set of enginieering challenges (keeping it dry).

About “leaving trees alone”:
Please learn more about how a forrest “works”. Biomass constantly grows and dies. A dead tree rotting in the forrest simply releases alot of it’s captured carbon back into the atmosphere – not a very effective carbon sink. 

donough shanahan's picture
donough shanahan on March 1, 2014

Can we implies the here and now which this article look at some element

Could we would cover your possibilities.

jan Freed's picture
jan Freed on March 1, 2014

Wind: Your phrase “we have practical if more expensive alternatives such as renewables” is not accurate. They are not more expensive, but far less.

The hidden costs of coal energy (Harvard School of Medicine study) are estimatated  to be about $400 billion/per year!  Or $.18 per kwh.  We pay that price, unknowingly, and scream about “carbon taxes”.

I read of a World Bank estimate of $500 billion/year “subsidy” of coal, perhaps based on this study?

Regarding this article: Yes the chemistry of steel and concrete production does release CO2.  But, that is small potatoes next to burning of fossil fuels.

 

Yes, steel and concrete require energy as well.  Yet, it won’t surprise that corporations, such as Apple, perhaps Tesla, are striving to do their thing on renewables.  Why not large solar farms dedicated to produce energy for steel and concrete?

The threat justifies the scale of the transition.

jan Freed's picture
jan Freed on March 1, 2014

Battleships weigh as much as 40,000 tons.  Recycled, that is a lot of wind turbines.  As we decrease our reliance on mideast oil, we decrease our need for such ships.  Another Escher, “hand drawing hand” picture.

Nathan Wilson's picture
Nathan Wilson on March 1, 2014

The amount of power available to a ship of a given size from the wind is very small.  The reason sailing works is because there is a velocity^3 relationship between velocity and power, and a velocity^2 relationship between velocity and energy consumed for a given distance travelled.

In other words, fuel powered ships can reduce their fuel consumption as low as desired by going slower.  No commercial business does this in the real world: ships and boat have a natural speed limit called the displacement speed, above which they must reduce the amount of water they “displace” by lifting up onto their bow waves “getting on plane” (which produces the classic speedboat wake pattern and pushes fuel consumption way up).  Essentiall all big ships travel at just below displacement speed (this speed increases with the length of the ship: around 10 knots in a kayak and 30 knots in an aircraft carrier).  

So large increases in fuel cost can be offset by small reductions in speed.  If ships travelled any slower, the saving in fuel would be offset by the higher cost of labor and interest on ship and cargo capital cost.  Of course adding sails makes the labor cost even higher, and parking the boat while waiting for the winds to shift would be totally uneconomical.

Robert Bernal's picture
Robert Bernal on March 1, 2014

Ok, so we agree that steel is better than wood for towers and such. Sure, it is energy and carbon intensive but we can sequester the carbon and use coal until fusion is fully developed. Then, there will probably be better ways than steel (future stuff).

As for trees, they WILL sequester the excess CO2 for about 50 to 100 years, then as you say, they will rot and release most of it. the soil will retain some of it for much longer (hence the necessity of letting nature do it, too). However, that future stuff (again) will actually remove the excess CO2 from the biosphere by means that we can’t even economically fathom.

Seawater extraction of CO2 (by self replication autonomous machinery???) is one way. The mining, grinding and spreading of olivine is another and I’m sure there are other ways. Some of these processes will simply “recycle” the CO2 for clean fuels. Others will acually sequester in mineral or geological form.

The obvious and only physical show stopper is access to a cheap and clean source of high temps. Autonomous machinery is needed to build the solar and wind, too, if we are to scale economically.

If humanity is not smart enough to figure out such “magic machinery”, then we should use close cycle nuclear for that high process heat and electricity. The closed cycle has many obvious advantages over today’s…

Robert Bernal's picture
Robert Bernal on March 1, 2014

I already did… Wood laminates are cool for buildings because they require less energy than steel. Wood would probably be best for small turbines, too.

Robert Bernal's picture
Robert Bernal on March 1, 2014

That last sentence is of particular interest and indeed backs up my claim that energy dense sources have a higher eroei. It is possible to use PV, wind and others at an economic disadvantage, but why limit ourselves to just the non nuclear renewables?

However, since hydro is a “gathered” form of diffuse rain (and it compares good), CSP can not be ruled out. It is also “gathered” by concentration, hence the need for atonomous machinery making helio-stat fields (for cheap). Hydro completely “wipes out the land” whereas CSP only partially “wipes out the land”.

Is it possible for the CSP’s high heat to power gas turbines…

Robert Bernal's picture
Robert Bernal on March 1, 2014

Scale is ALL the matter, as efficiency alone is just a half measure. Efficiency IS necessary but can not change the laws of physics. Powering 10 billion people’s water, food, mobility and entertainment needs requires A LOT of power!

Robert Bernal's picture
Robert Bernal on March 1, 2014

I like the beginning but what’s your solution?

Somewhere in this post, it is concluded that nuclear, hydro, and certain hydrocarbons (in that order) have the best eroei. Concentrated solar thermal is next on that list.

It is the only scalable renewable that offers high process heat. Nothing wrong with it except the economics (still). Land use is not necessarily land “destruction”.

Nevertheless, it can not compare to closed cycle nuclear.

Surely we are indeed headed into fossil fueled depletion into an over heated biosphere. We need to prepare for engineering on a fully developed resource (and energy) rich planetary scale. It is possible and MUST be done!

jan Freed's picture
jan Freed on March 1, 2014

Straw man:  what we advocate is a transition to renewables, which can be done, as Dr. Jacobsen points out in his Stanford U. study.  We don’t say ‘turn out the lights’.

If all those in this column who say “renewables are not practical” and who have no other suggestions other than “wait and see, maybe the climate scientists are exaggerating”, the wind would be howling throught these comments, like through a ghost town.

jan Freed's picture
jan Freed on March 1, 2014

Straw man:  what we advocate is a transition to renewables, which can be done, as Dr. Jacobsen points out in his Stanford U. study.  We don’t say ‘turn out the lights’.

If all those in this column who say “renewables are not practical” and who have no other suggestions other than “wait and see, maybe the climate scientists are exaggerating”, the wind would be howling throught these comments, like through a ghost town.

Paul Lindsey's picture
Paul Lindsey on March 1, 2014

The other little fly in the soup is capacity factor and reliability of power. For example, even if you could provide the process heat for a concrete kiln using only electricity, what happens when the power dips and the temperature drops? 

Before you convert to a 100% renewable, don’t forget to use some of those evil fossil fuels to mine, refine and form all the copper wire you’ll need for the 300% (NREL) increase in electrical power lines!

There is another source of high temp process heat besides solar ovens: HTGR. Oops, I said a bad word: reactor, as in nuclear.

jan Freed's picture
jan Freed on March 1, 2014

What is the EROI for a 2 mw wind turbine? What fraction of its life span?

 

What is the EROI of a solar panel? What fraction of its life span?

 

 

Did anyone answer these questions?  Sorry, if I missed it?

jan Freed's picture
jan Freed on March 2, 2014

Cliff: 

Do you happen to know how many acres have been sacrified to coal?  I think I read something like 5 million, and you remove the ‘overburden’ (farms and forests, for example).  The acreage will only increase to get at more coal, whereas solar can be sited on roofs and in deserts, and cows can be grazed between wind turbines each with a small footprint (of the turbines, not the cows).

I wonder if the coal ash that is dumped in streams is counted as acreage?

Robert Bernal's picture
Robert Bernal on March 2, 2014

Here’s a pdf on the EROI concerning various different energy sources including nuclear, wind, CSP, hydro, etc. It offers hope as long as we are not doped into believing that we can either “do it all” with expensive renewables (or that FF’s will last forever with no side effects). I believe it suggests that wind is not capable to power its own production from both an EMROI and EROI sense.

http://festkoerper-kernphysik.de/Weissbach_EROI_preprint.pdf

Steve Frazer's picture
Steve Frazer on March 2, 2014

Roberts(both commenters), today there are about 80 million acres of prime US farmland used for the production of biofuels.  The largest slice of this of course is corn for ethanol at over 40 million acres.  Soy, cannola, safflower, peanuts, switch grass, etc., all are bring grown for biofuels – direct use or recycled.

Your posiition on biofuels is common and is based on the numbers and impact of 1st generation feedstock.  We lobby against corn ethanol AND soy for biodiesel.  We agree, these business models do not make sense from an environmental perspective.  What does make sense is biodiesel from 2nd generation feedstock. 

Let’s do the math.  Soy generates less than 50 gallons/acre/year with 4 passes of heavy equipment while 2nd generation feedstock generates 500-850 gallons/acre/year with a single pass of heavy equipment.  First gen feedstock is grown on prime US farmlands – again, corn, soy, etc., while 2nd gen feedstock grow on marginal lands in the southwest and cannot be grown in the American heartland.  We are pushing to return those 80 million acres of farmland to food production.

You mention low energy density of biofuels – we agree – ethanol has about 1/2 the BTU/gallon of petroleum diesel, however, biodiesel contains 97% of the BTU/gallon of petroleum diesel and the cost of production is about 1/2 of petroleum diesel today and dropping with economies by scale.

Also, 1st gen feedstock has been determed to have a significant carbon footprint, however, 2nd gen feedstock offers a significant negative CO2 footprint. When analyzing the EROEI of 1st gen feedstocks we see a disappointing 1:1.27 for ethanol and 1.5 for soy, however, hardwood 2nd gen feedstocks offer a 1:24 return on energy.  This is higher than wind and NG, a factor of solar and 8x tar sands petroleum. 

We can be producing 40 billion gallons of biodiesel per year within 20 years and within 30 years replace 100% of all petroleum used for transportation fuels – all from US lands and create tens of thousands of good paying jobs.  Speaking as an Analyst and having worked for the DoD, DoE and 2 universities as a Research Engineer, it is our only replacement solution for petroleum.

My firm has 385,000 acres in managment today with a 22,000 member partner organization.  We’ll get it done.  If you have additional questions – please ask – maybe it will help others to understand the future of transportaiton.

Steve Frazer's picture
Steve Frazer on March 2, 2014

Sir Richard Branson already uses biodiesel blends in his ships and planes.  We are helping him increase the % of biodiesel over the coming years.  All quite doable.

Steve Frazer's picture
Steve Frazer on March 2, 2014

Actually, while on the surface, nuclear might seem to offer a high EROEI, in fact, per our real history, it does not once the total energy consumption per the total energy produced is understood. 

Note: We receive a great deal of communication regarding the 1:10 for nuclear power.  This ratio has been researched in-depth. Most U.S. tax payers are unaware that the DoE spent $3.2B in 2012 to manage the nuclear waste material from the Manhattan Project (WWII – 1942-1946).  Projections suggest the U.S. will continue to pay billions of dollars per year for the next 50-100 years before we might have what can be considered a low-energy management solution for this need.  There is no insurance firm in the world that now underwrites nuclear power plants – all handled by governments.  This is a major statement on the status of nuclear power plants and their future.

Here is a well researched chart – explanations can be found on our website under Products – Biofuels.

1:100.0 Hydro 1:80.0 Coal 1:36.0 Willow 1:24.0 Yellowhorn 1:18.0 Wind 1:18.0 Natural Gas 1:10.0 Nuclear 1:10.0 Petroleum – Conventional 1:9.0 Palm Oil 1:8.0 Petroleum – Exploration 1:6.8 Photovoltaic (tracking) 1:6.2 Jatropha/Tallow/Moringa 1:5.2 Soy biodiesel 1:5.0 Ethanol sugarcane 1:5.0 Petroleum – Shale 1:3.0 Petroleum – Tar sands 1:1.9 Solar flat panels 1:1.6 Solar collector 1:1.3 Corn ethanol
Steve Frazer's picture
Steve Frazer on March 2, 2014

Cliff makes good points here.  We install solar panels and wind turbines and the resistence to these installations is amazing – people actually come out to picket the job sites and new project permits have a 50/50 chance at best.  The renewable energy revolution has certainly stalled. 

Petroleum is real today and will be real for 50 more years and I doubt that all the coal plants will go away in the next 50 years in some areas of our nation. 

Then again, a 5% reduction in fossil fuel use is better than nothing and the economics of renewables is an inevitibility so the migration continues.

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