Nobel Prize winning biochemist says ALL biofuels are “nonsense.”

February 25, 2012

Similar posts from ClimateSanity
Taking Measure of Biofuel Limits 9/24/2009
Biofuels Leading to Disasters 12/28/2011

Hartmut Michel

Hartmut Michel

Hartmut Michel won the Nobel Prize in Chemistry for his work on photosynthesis.  So, it is fair to say that he knows a thing or two about energy transport and storage in plants.  Today he is director of the Molecular Membrane Biology at the Max Planck Institute for Biophysics.

He recently penned an editorial in Angewandte Chemie International Edition in which he hammered the use of biofuels for alternative energy.  Note that Angewandte Chemie International Edition has the world’s highest impact factor of all chemistry journals.  His simple but pointed criticism condemns all varieties of biofuels and supports my previous posts on this subject.1, 2

The problem is the inherent inefficiency of photosynthesis.  He points out…

“The photosynthetic pigments of plants can only absorb and use 47%(related to energy) of the light of the sun (“photosynthetic active radiation”). Green light, UV, and IR irradiation are not used…

Photosynthesis is most efficient at low light intensities. It is already saturated at 20% of full sunlight and 80% of the light is not used…In addition, high light intensities lead to photodamage of a central protein subunit of the photosynthetic apparatus…3.5 billion years of evolution have not been long enough to develop a mechanism for preventing the photodamage….

The dark reactions are limited by an insufficient discrimination between CO2 and O2 by the enzyme RuBisCO, which inserts CO2 into ribulose-1,5-bisphosphate. One third of the energy of the absorbed photons is believed to be required to remove the product of the O2 insertion…[and] photosynthesis depends on the availability of sufficient amounts of water, a condition that is not met during much of the day.”

Current biofuel technologies

Taken as a whole, conversion efficiency of sunlight to usable chemical energy in biofuels for commonly used technologies is extremely low.

“For German “biodiesel” which is based on rapeseed, it is less than 0.1%, for bioethanol less than 0.2%, and for biogas around 0.3%.”

But is it actually much worse than that when you consider

“… these values even do not take into account that more than 50% of the energy stored in the biofuel had to be invested in order to obtain the biomass (for producing fertilizers and pesticides, for ploughing the fields, for transport) and the chemical conversion into the respective biofuel.”

Michel confirms what I have pointed out before, biofuels of all stripes put a great burden on arable land.  He says…

“Taken together, the production of biofuels constitutes an extremely inefficient land use. This statement is true also for the production of bioethanol from sugar cane in Brazil.”

“Second Generation” biofuels

Some people hold out hope for “second generation” biofuels where the whole plant is utilized.  Michel explains that this is an illusion because the energy input for these types of processes in ever greater than for first generation processes.  For example…

“in the production of biodiesel by the Fischer–Tropsch process, hydrogen has to be added because syngas obtained from biomass contains insufficient amounts of hydrogen.”

More distant possibilities

“Hydrogen production by photosystem II would reduce the number of photons required by more than 50%.  However, this protein engineering task appears to be insurmountable at present.”


“Microalgae have been advertised as the ideal candidates for biofuel production. There are many unsupported claims about their efficiency, some even exceeding the theoretical limits of photosynthetic efficiency…the existence of photoinhibition and a poor RuBisCO will limit the advantages of microalgae together with the demands for growing and harvesting them.”

But biofuels will save us from CO2

Sorry, no.

“The production and use of biofuels therefore is not CO2-neutral. In particular, the energy input is very large for the production of bioethanol from wheat or maize, and some scientists doubt that there is a net gain of energy. Certainly the reduction of CO2 release is marginal.”


“Clearing rainforests in the tropics and converting them into oil palm plantations is highly dangerous because the underlying layers of peat are oxidized and much more CO2 is released by the oxidation of organic soil material than can be fixed by the oil palms…it would be even much better to reforest the land used to grow energy plants, because at a 1% photosynthetic efficiency, growing trees would fix around 2.7 kg of CO2 per square meter, whereas biofuels produced with a net efficiency of 0.1% would only replace fossil fuels which would release about 0.31 kg CO2 per m2 upon combustion!”

His conclusion

“Because of the low photosynthetic efficiency and the competition of energy plants with food plants for agricultural land, we should not grow plants for biofuel production. The growth of such energy plants will undoubtedly lead to an increase in food prices, which will predominantly hit poorer people.”

Read the entire editorial in context here (The Nonsense of Biofuels, Hartmut Michel, Angew. Chem. Int. Ed. 2012, 51, 2–4)

Here is a video of Michel making the same point.

His Noble Prize was for the determination of the three-dimensional structure of a photosynthetic reaction centre, as seen here


  1. Reblogged this on pindanpost.

  2. It’s possible to produce almost 60% H2 syngas with almost 2:1 H2:CO. So it may be economical to convert various bio-wastes to fuel.

  3. […] Nobel Prize chemist Hartmut Michel debunks the value of biofuel as the green gold rush picks up […]

  4. Hartmut is spot on. I would, however counter with the example of 1,2,4 trinitrobutane where a biological semisynthesis allowed for the elimination of borate waste streams (and therefore a huge decrease in cost to synthesize). There are some opportunities in specialty fuels for biology to produce a better or cheaper product.

    • excuse me, butanetrioltrinitrate.

  5. Dr. Michel may be right or not about the overall issue, but presenting the low efficiency of photosynthesis as a central argument is incorrect. Since the amount of solar energy available is practically limitless, the efficiency of the converter, by itself, doesn’t tell us anything. What matters is the efficiency of *producing* converter units.

    For instance, would you prefer to heat your house through a fictitious 90%-efficiency solar heating unit that would cost $10,000/year to acquire/maintain, and would hardly cover your needs, or would you prefer to collect free wood in a forest surrounding your house? (I’m not saying this example is realistic, or that collecting wood is the solution, I’m just exagerating the qualitative differences to show that the proposed quantification cannot be right)

    The real question is the efficiency of growing and collecting plants usable as biofuel. Dr. Michel touched this issue in his video, but very superficially, since this is obviously outside of his area of expertise.

    • What matters actually is the resources required for each unit of energy. In this case, it is the amount of land, fertilizer, water (especially from aquifers), and the amount diverted from food production. “Presenting the low efficiency of photosynthesis” is in fact central to the point. You have to calculate what resources are to be expended for each unit of energy produced. The efficiency of photosynthesis puts an upper limit on the unit energy per unit resource ratio.

      Burning wood, for example, is most definitely not a viable solution for replacing a significant protion of a modern society’s fuel. I have calculated this before (perhaps a blog post would be appropriate). As I recall, the entire wood consumption for all uses would have to be doubled to yeild about 1% of our total energy usage. It would not take long to consume all the trees in the country to get a small amount of our total energy.


  6. https://plus.google.com/u/0/115056313943520401920/posts/H4NSNV6K6ah

    (Will not reply here further, fwiw.)

  7. Hemp, the genius forgot to mention hemp.. And it’s not nonsense.

  8. Using propane it costs roughly $700/month to heat my home.. I switched to wood heat, now costs $120/ month, and it burns much hotter… For the last 2 years I have heated my home for free using fallen trees that fall during storms..

    Hemp as a biofuel makes much sense.. It grows pretty much unattended, it’s very low maintenance, not to mention the fact that other goods can be made from this same WEED.. Makeups, Medicines, Textiles, Concrete, Food, etc etc etc…

    The man is apparently anti-Hemp.. Drill Baby Drill! What the fuck ever!

  9. Reblogged this on Eliot Pearson on WordPress and commented:
    I’m not sure if food prices would increase if certain plants are used for biofuels. However, I don’t have a noble prize.

  10. The Nobel must look at agave, bamboo, opuntia… awesome yields
    One hectare of agave can yield over 10,000 gallons of ethanol per year (average, since agave takes 6-8 years to mature) or over 50m3 of biogas per tonne. CAM plants use light, soil and water most efficiently amongst all plants!

    • The “promise” of agave has yet to be realized.

      But let’s make the (very liberal) assumption of 10,000 gallons of ethanol per acre per year. Ethanol has an energy content of 24 kilowatt-hours per gallon. So that works out to 240,000 kilowatt-hours per acre per year.

      The same Mexican acre with PV would yeild about 1,500,000 kilowatt-hours.

      But a kilowatt-hour of electricity from PV is much more useful than a kilowatt-hour of energy content of ethanol because of the high losses that occur on converting the chemical energy of ethanol to useful work.

      I hope that I am wrong, but I do not have high hopes for agave.


      • No plant on Earth converts more than 3-4% of the sunlight into carbohydrates. None. Solar cells covert between 12 and 30% of sunlight into electricity. So an acre of solar cells in Iowa will produce 3-10 times more energy than an acre of corn. Simple physics. Conversion of the corn to alcohol is energy intensive, so that 3% of sunlight captured gets whittled down pretty quick. Add in the 30% efficiency of ICE engines…and well, 0.1% sounds about right.

        Here is a thought problem. Since ethanol distilleries make ethanol, a fuel, how many use the ethanol they make as a heat source to make more ethanol? I mean they have their own fuel source to utilize. The answer is…none. Most use coal to generate the heat they need to distill the ethanol. That tells you all you need to know – corn ethanol is simply a roundabout way of using coal to power cars. Stupid.

  11. […] who miss chemistry class can read the ClimateSanity post here, but the CliffsNotes version will say that Michel believes it’s a bad idea to depend on […]

  12. I did a rough calculation of how much solar PV it would take to run an EV 15,000 miles per year (the number of miles the EPA uses for it’s annual cost estimates) and I compared it to the amount of land it would take to grow enough corn to make enough corn ethanol to fuel an E-85 vehicle. It takes about 2 acres of corn for the E-85 car and 24 square meters of PV for the EV. That’s a ratio of about 350 to 1. This is just a ballpark number but…. WOW!!!

  13. Budhist monks who sit immobile and fast for days under the shaded trees are best photosynthesis efficiency model for mankind to emulate as the world will get overcrowded and the need for energy and food will far exceed the world population. Stop driving fossil fuel engines. Stop traveling on jet planes. Stop consuming beef, pork, chicken, eggs, milk, bread, rice. Cows and chicken are the worst photosynthesis energy transfer media.

    Zero emission of CO2.
    Zero consumption of foods.
    Zero population growth.
    These are ideal goals for a sustainable planet earth.

    • John,

      Thanks, but this is not exactly the solution to our problems that I am looking for.

      Best regards

    • Haha, this is a joke right???

      Tell you what, go and practice what you preach and we’ll talk later…or maybe not! Idiot!

      • My Buddhist monk’s comments to show how you can derive to any finality when pushing your theory to the limits. Harmit Michel concluded that because the lower photosynthetic efficiency all biofuel plantings are “nonsense” This is because he is not a specialist or an agronomist, or an inventor in creating new species of feedstocks where fuel and food can and will coexist. People who laughed at the US dependency in OPEC oil, within the past few years, are now at awe at YS fracking technologies to will make the US energy independence and a top oil producer.

  14. […] Flickr de Andrew Stawarz | Flickr de tonrulkens Via: Autobloggreen Fuentes: Climesanity | Artículo original de Hartmut Michel En Tecmovia: Biocombustibles: ¿problema o […]

  15. The ‘requirement’ for bio-fuels becomes mute when you discover that Hydrocarbons are a natural compound throughout the Universe. The banker controlled faux democracies have a three-prong Carbon war….Carbon climate forcing….sustainable ‘green’ energy….and finite fossil fuel. The reason there is Methane under every rock you frack is that it is in constant production by the planets fission process. See “Fracturing the Fossil Fuel Fable” at Faux Science Slayer, along with “Fractional Reserve BAnking Begat Faux Reality”. When your banking system is a Ponzi scheme, then your ‘leaders’ MUST lie. Find and share Truth….it is your duty as an Earthling !

    • I am certain that methane is not produced by fission.


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: