algae biofuelsLast week, Frank Ciampa, posted Algal Biodiesel: Pros and Cons, his response to Could Algae be the New Corn?, written by Julia Verdi.   This week, Eamon Keane, responds to Julia’s post, explaining why he does not feel that algae biofuels is a good alternative to oil.

by Eamon Keane

I thought this title was actually going to critically analyse algae. Instead there were no figures, just word based arguments. You will be aware of the study which came out in January which showed algae to have significantly higher emissions than diesel. Also, the non-solar energy invested in algae is the same as the energy contained in algae (EROI=1). Then there’s the small matter of cost, far north of $10/gallon. The DOE says they are at least 10 years away, and if you read their document there are so many issues involved, I don’t hold out much hope.

American presidents have been promising for decades to wean Americans off foreign oil. Obama is the latest, with $44m recently allocated to what’s widely regarded as the ideal solution – algae.

Algae aren’t new, they’ve been studied for over 80 years. In 1978 Carter launched the Aquatic Species Program to get oil from algae. It was defunded in 1996 by Clinton without any noticeable success.

Recently, a paper by the University of Virginia undertook what is essentially the first Lifecycle Analysis (LCA) of algae for biofuels. The paper, which I’ve read, is behind a $30 paywall but the supporting info (.pdf) with all the calculations is not. The results are not good. The study only accounts for the energy and emissions for the algae biomass before processing to get a liquid biofuel. I’ve adjusted the results assuming 50% lipids which reveals the following comparison:

Co2 MJ of Diesel vs Algae

Figure 2 shows the energy invested over the lifecycle versus the energy in the algae biomass:

Energy Return on Investment

Energy Return On Investment (EROI) is critical to understanding new energy sources. In the past oil required almost no energy expenditure to extract – you just pricked a hole about 15 feet deep and out it gushed.

Figure 3 shows the EROI for other energy sources:

maximum energy return on investment

If recoverable oil reserves are 2 billion barrels but it takes 1 billion barrels worth of oil energy to extract them, then you’ve actually only got 1 billion barrels of reserves.

So clearly algae aren’t the sort of ‘free energy’ from the sun as they might be portrayed. The energy inputs break down approximately as follows:

Sources of Energy Output

The study assumed the CO2 was a pure gas which accounts for the large energy input. The suggestion is of course that you would co-locate it with say a coal plant and feed the flue gas, however this results in an average drop of 50% in yield. You can quibble about the energy inputs if you like, but take, for example this quote from the DOE’s June 2009 Algae Biofuels Technology Roadmap (.pdf):

Nonetheless, this analysis shows that any harvesting/extraction scheme involving dry algae is energy prohibitive, requiring at least 60% of the energy content of algae. There is thus a need to develop strains of algae with much higher energy content than available today.

Furthermore take a look at the process flow diagram and all the times energy input is required:

algal biofuel value chain

This was for an open pond environment, the energy inputs for a photobioreactor would be much higher. In every report I’ve read, they’ve been dismissed as impractical and much more expensive than open pond. The former head of the Aquatic Species Program refers to them as bizarre contraptions.

So open ponds are the only show in town. The problem with them is that they’re open to the atmosphere and thus invasive species. Take this quote from an algae expert (.pdf):

Although large scale microalgal culture has now been undertaken for over 40 years, our experience is still limited to a few species, and even for these, our understanding of their ecology is still very incomplete.

Not exactly inspiring considering there are millions of algal species and viruses.

You can talk about using manure from farms or using wastewater to supply the nutrients. The problem with manure would be the energy needed to collect, transport and extract nutrients from it, and also the fact that most of it is already left on fields as natural fertilizer. Furthermore algae require the exact right ratio of nutrients for optimal growth, which may not be forthcoming from manure.

Using algae to clean wastewater of nutrients is actually a good idea, but it’s not going to yield commercial quantities of algae, and if you wanted to scale it up you’d still have to add lots of nutrients.

It is thus quite difficult to assign any confidence for the future of algae. Because of the harsh realities, you’ll never find a life cycle assessment in an algae biofuel press release. However, quelle surprise, the algae biofuels association disputes the findings and says it is using “outdated data”. Show us the new data, then.

© 2010, Eamon Keane. All rights reserved. Do not republish.

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Author: Eamon Keane (1 Articles)

  • Gregory Xedis

    The world needs food fuel and shelter (peace) All products like wafer and particle board weighs twice as much as there counterparts by the time you get through manufacturing shipping them the cost is to much. We all know that most things that come from Washington always have not for profit they need to cut this now. They have not supported the algae research like the independents have invested their own money into the best product to hit the market in decades and leave this to these people to create. Ethanol will fall in place as needed without government pushing it. There is three processes in the works now dry, tar like and wet extraction that is all useable that will determine if Ethanol is needed. If they built a true Diesel engine we would be using algae oil instead of Vegables oil or petroleum by now and skip the cracking that causes all the Rif. if you need proof of this google Algae in google alerts or short cut

  • Steve Gunn

    Take a look at Origin Oil, most of the above problems have already been solved.

  • Eamon

    Hi Steve,

    I have looked at Origin Oil, and am not convinced. One of their inventions is a frankly ridiculous photobioreactor which uses artificial light! They have not released a lifecycle assessment of the energy costs. Where I first posted this article (, an algae grower chimed in with the comment below. It reveals the science behind why Origin Oil’s efforts to have algae secrete oil are likely to be unsuccessful.

    From ddugger:
    “There is thus a need to develop strains of algae with much higher energy content than available today.” DOE’s Algae Biofuels Technology Road Map.

    This is where a large amount of proprietary capital investment has gone in algae oil R&D. Several things make this conclusion laughably naive – algae only increases lipid production under stress during which their population density dramatically decreases as does the net lipid yield. Secondly, even if you could genetically modify algae to produce higher lipid levels – in order for a plankton algae to produce algae above it’s naturally selected optimized natural levels – the algae has to increase it’s density of non-lipid cellular components to offset the added buoyancy of the lighter than water lipids it’s producing. This ballasting metabolism has is very finitely limited. Otherwise the algae float and die before they ever come close to peak optimal production.

    The only way by these biological limitations is using macrophyte attached algae plants – which tend to be more two dimensionally limited photosynthetically and probably less efficient lipid production wise than terrestrially higher evolved plants. Coincidentally, terrestrial plants are producing biofuel at far lower costs than algae, but still more than a 100% over petroleum costs.”

  • Ben Lubbon


    Take your pessimistic knowledge and turn it into can-do optimism. Be part of the solution…

    OriginOil has released a lifecycle assessment of the energy costs.
    This data was produced from the first stage of their CRADA with the DOE Idaho Laboratory.

    OOil CEO Riggs Eckelberry gives a great response to the UVA study at…

    And, do consider most co-location sites have enormous heat sources. Heat creates energy to power up onsite needs and produces another revenue stream in selling energy offsite. I’d tell you how yet it’s proprietary.

    Steve and Gregory, keep up the support; sooner than later, OriginOil will prevail.


    Ben Lubbon

  • Eamon Keane

    Optimism for optimism’s sake isn’t helpful.

    I had viewed that Origin Oil presentation before. Unfortunately it does not have what I was referring to by ‘energy costs’. A lifecycle energy input vs energy output yields an Energy Return on Energy Invested (EROI). Like, you have to add up the energy needed to make the plastic photobioreactor and so on.

    I’ve no doubt they’ll be able to pony up to some industrial site and get some waste energy. The document says nothing about how they’re going to get the electricity for the light in the helix photobioreactor. It just says ‘waste energy’. That is in the form of heat. It will more than likely be low grade heat, because if it’s high grade heat then the facility should already be recycling it to cut down on fuel bills. If the industrial site had large heat and power loads, then they should already be using a Combined Heat and Power (CHP) unit and using the leftover heat from power generation for the site’s thermal load.

    So, they’ve got some waste heat, probably at less than 300 degree celsius. Your efficiency at generating electricty from that is going to be rather low and it would also be expensive. If it was cost effective, the industrial facility would already be doing it. That will keep the algae warm at night and keep them from canabilising themselves, but will not generate the light needed to grow the algae.

    So the electricity will have to come from the grid, mainly from fossil fuels one suspects. Then I’d like to know what efficiency the generated light is absorbed at by the algae. There is no mention of that in the linked presentation.

  • Ben Lubbon

    Excellent points; you obviously know your technology.

    Yet, rather than being a gatekeeper to “NO;” your valuable insight could provide solution.

    Are CHP units already being deployed?

    Regardless, with a bit of engineering can-do, the waste heat may be redirected by great thinkers like you.

    By the way, what’s the EROI in scrubbing oil off a pelican?

    And, what’s the EROI re your can’t do punditry?

    Accentuate and enhance the positive. For if negative attitudes prevailed in civilization’s short brief history; humanity would have never discovered fire or the wheel!

  • John Lees

    It is not pessimism to debunk overreaching claims. Allocating scarce resources, like R&D funds, water, and high-insolation land to unproductive technologies will not help anybody. We have to be coldly rational, I’m afraid.

  • Dehran Duckworth

    Speaking of food, clothing, shelter, and peace………..Our silver bullet solution is right under our noses and has been as long as we have been on the planet. Intelligent people, take notice.
    Can anybody guess what the answer to these questions is?

    1. What plant produces more biomass, fiber, oil, and protein per acre per year than any other plant.

    2. What plant absorbs more co2 from the atmosphere than any other (one acre in one season absorbs the same amount of co2 as an acre of trees in 10 years)

    3. What plant requires limited fertilization and can survive from from Canada to Venezuela on limited water if need be?

    4.What plant, if planted on all of America’s fallow ground, could produce enough biomass for our electricity generation needs (replacing coal without retrofits), enough biodiesel feedstock oil to make America energy independent, and produces some of the highest quality protein on the planet that could effectively feed humans and animals all over the world without disrupting the current food chains?

    5. What plant’s oil can be used to produce high quality bio-plastics, industrial lubricants, and clean burning engine fuel, effectively replacing petroleum all together with a completely non toxic alternative that would flood our country with jobs and clean our air?

    6. What plant has no psychoactive or narcotic properties but remains scheduled federally as an illegal drug and federally prohibited for industrial use under the guise of the misinformation that it is the same plant as its close cousin that does have mild psycho-active properties?

    7. What plant can still be found growing prolifically in the wild all across the country and the world, left over from a time when all farmers were required to cultivate it?

    Hints; It was a threat to big oil (e.g.Standard Oil) and synthetics (e.g. DuPont) at the dawn of the industrial revolution, and lobbied into total obscurity and even criminality by those corporate interests, along with alcohol at a time when bootleggers were using and selling their ever-clear as fuel for cars, decentralizing the energy chain.

    Henry Ford fabricated an entire vehicle with it, and Rudolf Diesel used its oil in his original engine design citing the need of the common man to have a machine to work his land that could run off of the fuel he could grow in his back yard (Standard oil did not concur, Rudolf Diesel took a swim).

    American farmers once paid taxes to the government with this crop instead of money.
    Parachutes, uniforms, American flags, and original Levi Jeans were once made with this plant material, George Bush Sr. in fact owes his life to one of these very chutes.
    The sails and ropes that carried the first settlers to the new world and beyond were made from this plant.
    Wake up America, give your kids a tall glass of chocolate Gulf water, go to the beach and play in the oil, quit fishing and eating seafood, take the kids outside for a deep breath of filthy air, let them chew on toxic petro based plastic toys, let them play by the refineries and get cancer.
    If we continue with fossil fuels our children have no future While Dick Cheney and BP and the other oil companies reap unprecedented profits at our expense. How long do we let the likes of them control our lives and environment? The time is now, wake up America!

    • Rohan Choukkar

      Hemp, by any chance?

  • Chris Younger

    I agree Mr. Duckworth. I think this plant you speak of is such a threat owing to the inability to control it.
    I don’t expect this old money system to lay down and die either, they’ve been fairly effective in keeping it underground and shrouded by fear for longer than you and I have been alive.

    Not to mention the money put in the pockets of legislators to keep this …product out of the market. Paid for, ironicly, by the sale of the plant illegally and/or the large amounts of money to be made by keeping the supply of crude limited, thus the price nice and high.

    It would be wonderful to think that people might be waking up to this reality a little with the gulf being ‘chocolate milk’, But (pardon the little joke) I wouldn’t hold my breath.
    Be well bro