Can You Make a Wind Turbine Without Fossil Fuels?

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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

THIS POST ORIGINALLY APPEARED AT THE ENERGY COLLECTIVE

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27 thoughts on “Can You Make a Wind Turbine Without Fossil Fuels?

    Barry Woods said:
    June 11, 2015 at 11:36 am

    Each windturbine has quite large quantities of rare earth metals as well, the motor/magnets, etc?

    do you have any figures for these components?

    Like

      Robert Wilson said:
      June 11, 2015 at 11:45 am

      You are the one saying they are “quite large”, so on that basis I’m assuming you have actually read some figures in the past, otherwise you wouldn’t be asking me to provide you with them.

      Like

      Ulenspiegel said:
      June 14, 2015 at 1:11 pm

      The finest onshore wind turbines are built without rare earth metals.

      Like

      Dimitri Harakidas said:
      June 16, 2015 at 10:28 am

      To be clear in a couple of things. The question here is on how to be powered by renewable sources and not a particular source. Basic engineering says that the fewer the moving and/or overall parts the more efficient. Every one should think and make up their minds about it. Logic can not be defied though.
      Secondly, maybe we should change the model. Rather than forcing the consumption side of the economy to be renewable energized, effort to make the production side of the economy renewable powered? Imagine that as much heat required to run any kiln could be produced by a solar electric government facility near by? Imagine converting their power source to renewable? And everyone is happy 🙂

      Like

    duffer70 said:
    June 11, 2015 at 12:19 pm

    Maybe you missed the question mark at the end of Barry’s first sentence, Robert? Each megawatt of wind turbine capacity currently uses about 200 kg of neodymium, apparently. http://blogs.ei.columbia.edu/2012/09/19/rare-earth-metals-will-we-have-enough/

    Like

      Robert Wilson said:
      June 11, 2015 at 12:42 pm

      Yes. Rare earth use. The latest in a long line of pseudo-reasons to oppose wind turbines. The golf club bores of the internet.

      Like

    Mark said:
    June 11, 2015 at 3:20 pm

    Robert-loved the picture of the engine that will power a ship.

    The value of energy dense materials to power the equipment that let us accomplish tasks was brought home for me last year in my little corner of globe. My gold rush founded town doubled in size in less than 4 days last summer during the King Fire- that ended up burning close to 100,000 acres of mostly National Forest lands in the American River watershed. 10,000 personal got to my town via the fastest way they could get here- using FF powered transportation. Many of the tasks needed to combat the fire entailed using human powered tools such as shovels and rakes. The FF powered tools/equipment such as chain saws, generators, helicopters, fixed wing fire aircraft, and hundreds of fire trucks of various configurations put a bit of a strain on our local infrastructure of roads, and refueling capabilities.

    One of these days I need to head over to my little airport to verify my supposition that more aviation fuel was sold during the week aircraft were used to fight the fire than any other similar time frame in the 90 years the airport has been in operation.

    Like

    Mark Brinkley @slopingsite said:
    June 11, 2015 at 7:24 pm

    Isn’t syngas the answer? http://en.wikipedia.org/wiki/Syngas

    Like

      Robert Wilson said:
      June 11, 2015 at 7:34 pm

      People put it forward as answer. But I remain very skeptical.

      If you are creating a carbon based synthetic fuel where does the carbon come from? If it comes from capturing co2 from fossil fuel combustion, then what’s the true benefit? Big efficency loss in the original power plant. And anyway, if we capture the carbon dioxide, why not just bury it instead of going to the effort of converting it to another fuel?
      Then there is efficiency. Let’s say the synthetic gas is replacing directly used natural gas for heating, whether in industry or to heat homes in houses. This will be woefully inefficient and likely mind bogglingly expensive. Just compare the current price of a kWh of natural gas with a kWh of electricity from a wind turbines. What is it? A quarter of the price? Ok. So you then convert this wind electricity into synthetic gas. At best that’s a 50% efficient process. This makes it 8 or so times more expensive than old fashioned take it out of the ground methane. This ignores the costs of the kit to do the conversions. It would also ignore the fact this kit would have to run at a fairly similar load factor to wind farms, which would make them a disaster.

      So no, I’m not so sure syngas is the answer.

      Like

        Mark Brinkley @slopingsite said:
        June 12, 2015 at 4:08 pm

        To answer your first point, surely the aim of syngas would be to suck carbon out of the atmosphere. It would be performing the same trick that biofuels are designed to do, only forcing the process using electricity rather than relying on photosynthesis.

        It would be ruinously expensive if compared to today’s relative costs of natural gas and renewables. But this only works as an idea if we are able to create far more electricity than we actually need to run the planet’s power networks and to be able to dump the surplus power into manufacturing. If the power is genuinely surplus to requirements, the cost would fall to incidental levels and the efficiency arguments would fall by the wayside too. IE It simply wouldn’t matter if the process was inefficient if the power supply was over abundant. You could even design plants to run only when surplus power was being generated.

        Another way to look at the problem is to ask “Expensive compared to what?” You could argue that burning fossil fuels is ludicrously expensive if the true costs were to be charged.

        Like

        Robert Wilson said:
        June 12, 2015 at 4:40 pm

        Lots of issues here, and we could debate all day.

        Cost. I haven’t seen any economic analysis on whether storing excess renewables in this way is smart from a mitigation point of view.

        But let’s say you had two choices. One, you can spend money on kit to store excess wind energy. Two, you can spend money on more wind farms. Is there any reason to automatically assume the first choice is cheaper?

        The key thing to make it work would be cheap and preferably predictable low carbon electricity. So, I can imagine it working best with desert solar or nuclear. Maybe there will be a future where Germans import synthetic gas produced using Chinese nukes. Who knwos.

        But until this stuff is tested and costed it’s hard to see whether it would be anything other than a pipe dream.

        Like

    Enviro Equipment, Inc. said:
    June 11, 2015 at 7:31 pm

    Wow. I knew that it was ridiculous to suggest that the world could be”fossil fuel free” in the next several decades but until I read this article I didn’t realize just how ridiculous that claim was.

    I wish there was a realistic estimate of how many barrels of oil, tons of coal or cubic meters of natural gas it takes to produce one average size windmill or 10 solar panels.

    Like

      Robert Wilson said:
      June 11, 2015 at 7:36 pm

      What really matters is that it takes much less fossil fuel to make wind electricity than is in an equivalent amount of fossil fuel energy. The aim to take things to zero is a distraction from the aim to reduce.

      Like

        RenewableFanatic said:
        June 17, 2015 at 5:30 pm

        I wish that you had also stated this in the article. I mean if we are using fossil fuels to manufacture windmills and solar panels, what we are ultimately doing is using fossil energy to displace fossil energy via renewables. Kind of like treating sewage water and making it drinkable (or at least usable for non-drinking purposes).

        Like

    Bobbi Fox said:
    June 12, 2015 at 5:41 am

    There are two elements that aren’t mentioned in this evaluation. One is industrial wind turbine operating capacities; Germany, as an example, saw a 14.8% of rated capacities for its’ series of turbines for 2014. The second, even more important in my estimation, is the lifespan of the turbines themselves – estimated to be 20-25 years (a figure replicated in ‘break even’ fiscal points, if some wind power investors are to be believed). Both of these add questions: would 14.8% of an energy source keep one warm at -40 in a Canadian winter, and is it an acceptable process to have to repeat all of the above processes every 20-25 years, to prevent ‘failure’ of operating turbines? Just a thought. Thank you for your work – valid points.
    Germany – 14.8% rated capacity in 2014:https://wryheat.wordpress.com/2015/02/12/german-wind-power-fails-a-cautionary-tale/
    Engineering and Lifespan data: http://www.windpowerengineering.com/construction/projects/windpower-profitability-and-break-even-point-calculations/

    Like

      Ulenspiegel said:
      June 14, 2015 at 1:20 pm

      Bobbi, Bobbi,

      most German wind turbines are quite old, this gives an low avarage capacity factor. However, to use this number for projections is very stupid propaganda because the old turbines are being replaced with modern ones.

      What is the capacity factor of modern German onshore wind? it is in the 25-40% range. The yield would be better in northern America.

      BTW You could use heat pumps to get higher efficiency.

      There is no doubt that modern wind turbines offer a affordable solution.

      Like

        Robert Wilson said:
        June 14, 2015 at 3:51 pm

        Please provide evidence for these claims. How is anyone to know if either of you is talking sense?

        “It is in the 25-40% range”. This is amazingly vague quantification.

        Like

      Bobbi Fox said:
      June 15, 2015 at 4:03 am

      Mr. Wilson: Please note that I provided a link to the exact study which cited the percentage of overall annual rated capacity in Germany in 2014. I do not make ‘generalized’ claims, nor ones that are not backed by data, as some have.

      If anyone reads German, here is the study and its’ calculations/methods: http://www.eike-klima-energie.eu/news-cache/baden-wuertemberg-kann-alles-ausser-windkraft/
      Or as an alternative, here is yet another English version/interpretation of the results of the above study – all citing 14.8%:
      http://notrickszone.com/2015/02/07/germany-2014-report-card-is-in-its-25000-wind-turbines-get-an-f-averaged-only-14-8-of-rated-capacity/

      Please do not mistake me for those who challenge statements without providing a data source. Thanks again for your efforts to help bring understanding of the above issues.

      Like

    John Weber said:
    June 12, 2015 at 10:08 am

    It would be elegant if wind and solar energy capturing devices could actually maintain a modicum of the wonderfully rich lifestyles many of us live. I believe this is a false dream and that BAU (business as usual) is not sustainable or “green” nor really desirable for the future of the earth or even our species.

    I have researched the energy requirements and the CO2 emissions for just the rebar and concrete used for the base of a 2.5 megawatt wind energy capturing device (wind turbine). Notice also all the equipment needed throughout the process of making and installing; these in themselves have an input of energy the materials. There are charts and pictures. It is sobering.
    See charts and data at: http://sunweber.blogspot.com/2014/11/prove-this-wrong.html

    Like

      Robert Wilson said:
      June 12, 2015 at 10:10 am

      This sounds more like an advert for your blog than a comment.

      Please provide an actual comment.

      Like

        Tony Phillips said:
        June 15, 2015 at 10:53 am

        As those of us who work with energy (especially the geologist’s, and yes I’m one too) can see that the replacement (of fossil fuel with renewables) and a business as usual consumption scenario is impossible; especially in one fell swoop. So we must reduce consumption (probably by orders of magnitude) and yes this will drastically reduce mining for iron and fossil fuels; and may imply a virtual shut-down of mining activity in spurious mining such as gold which is not necessary at all.

        Is it really necessary to be that rude about Mr Weber’s comment. It is right on topic (as I’m sure you’ve seen) and 3.8 million new wind machines is impractical.

        Like

    Robert Callaghan said:
    June 12, 2015 at 11:22 am

    ► Wind turbines produce 25% of their rated energy 90% of the time.
    ► It takes 10X more intermittent electrical energy to displace one unit of fossil electrical energy.
    http://www.nature.com/nclimate/journal/v2/n6/full/nclimate1451.html?WT.ec_id=NCLIMATE-201206
    ► We can’t replace billions of wind turbine systems every 30 years and save earth.
    http://www.fastcoexist.com/3044467/a-periodic-table-of-elements-that-the-world-is-running-out-of
    ► Recycling their alloys is difficult and uses more energy than mining.
    ► 40% Green Energy requires 200% more copper says John Timmer of Ars Technica.
    http://arstechnica.com/science/2014/10/making-lots-of-renewable-energy-equipment-doesnt-boost-pollution/
    http://www.climatecentral.org/news/renewable-energy-needs-huge-mineral-supply-16682
    ► Peak copper hits 2030 – 2040 says Ugo Bardi.
    http://energyskeptic.com/2013/ugo-bardis-the-universal-mining-machine/
    ► Post peak copper production cannot accelerate at any price says Dave Lowell.
    http://www.mining.com/web/peak-copper/
    ► This is true of any post peak mineral production.
    ► There is no real substitute for copper says Mat McDermott of Motherboard.
    http://motherboard.vice.com/en_ca/blog/there-are-no-substitutes-for-the-metals-in-your-smartphone
    ► We mined 50% of all the copper in human history in just the last 30 years.
    ► 100% green energy requires 500% more copper.
    ► Peak minerals includes more than just copper.
    ► By 2050, expect to be past peaks for tin, silver, nickel, zinc, cadmium and more.
    http://www.chelseagreen.com/bookstore/item/extracted:paperback
    ► Most new hi-tech green energy exotic mineral requirements are energy-cost prohibitive.
    ► We move some 3 billion tons of earth per year to get 15 millions tons of copper.
    ► We can’t afford to mine 500% more copper at ever lower concentrations.
    ► We cannot recycle it into existence.
    ► We cannot conserve it into existence.
    ► Substituting aluminum for copper wire takes 5X the energy and is a brittle fire hazard.
    http://www.fastcoexist.com/3044467/a-periodic-table-of-elements-that-the-world-is-running-out-of
    ► Google’s own Stanford Phd, green energy experts, Ross Koningstein and David Fork, tell IEEE Spectrum why … green energy “simply won’t work” and is a “false dream” without major lifestyle changes.
    http://www.theregister.co.uk/2014/11/21/renewable_energy_simply_wont_work_google_renewables_engineers/

    Like

    howgreenisthis said:
    June 12, 2015 at 8:15 pm

    Reblogged this on How Green Is This.

    Like

    wili said:
    June 16, 2015 at 6:14 am

    Are you familiar with this work? http://www.monbiot.com/books/heat/
    He claims that cement or a reasonable equivalent can be made that will not be a net producer of CO2.
    Aren’t some large mining machines run now on electricity?
    Can we start repurposing/recycling steel for such uses? Does it all have to be newly made?

    These points aside, I think your overall point is very valid. Green BAU is a pipe dream. We can’t continue our industrial society at its current frenetic pace. We have to reduce our economy to a level where it is making minimal impacts on the climate and other vital systems of the earth, even as we continued to work toward the most efficient and sustainable forms of energy generation.

    Few want to face up to this fact. Thanks for trying to make it clearer.

    Like

    Grant (NZ) said:
    June 30, 2015 at 5:47 am

    Are oil and natural gas “fossil fuels”? is there any evidence of a biotic past to crude oil?

    Like

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