Another thought on Algae

I occasionally write about the potential advantages that might come from growing algae as a source of biodiesel and other liquid fuels. However I have also tried to point out that it is not something that will allow you to drive your truck for ever on the green slime that is growing in your pond, starting tomorrow afternoon.

There is a long process of validation and scaling up that will be required to construct a viable productive industry, large enough to make a significant contribution to the nations supply. And by significant I mean in and around the million barrels a day mark. In an earlier post I tried to delineate some of the technical issues, and in another post the reasons why it will likely take between ten and twenty years before we see that level of success.

To get into that process will, of course, require some initial ideas with promise, and a significant amount of investment (for example General Atomics, Exxon, BP and Boeing - to name but four of the companies involves with very large investments in the potential of the technology). However it is often not clear how far along these developments are, relative to the hurdles that they have to overcome.

However, there has been an article by Emily Waltz in Mother Jones that recently pointed out to possible investors in the technology that they need to do at least the usual levels of due diligence before investing in the technology. It points out that there are something on the order of 200 companies worldwide that are working on the topic, but that it is not yet possible to purchase commercially available oil from any of them. It cites, in fact, the journey of one individual who visited apparently 40 of the companies in the United States, and concluded that he was better off starting up his own company than going to work for any of those that he had visited.


I remain convinced that there is a considerable potential for the process to become viable. However there are a considerable number of hurdles that have to be crossed before that point can be reached. An immediate rush to large scale trials can gloss over some of these problems with unfortunate results, not only for that individual project, but also for the reputation of the technology as a whole.

This is perhaps most recently demonstrated by the fate of Greenfuel Technologies about whom the above article does not stint its scorn:

The company insisted it could produce oil at the equivalent of more than 44,000 gallons per acre per year. Venture capitalists ponied up more than $33 million between 2005 and 2008, a sizable amount for an energy startup of its size.

GreenFuel's pilot project proved twice as expensive as projected, and the company folded in May. "They had no technology—nothing except PR for outrageous claims repeated often enough to sound believable to some poor souls who bought into their fibs," says John Benemann, a former researcher at the University of California-Berkeley who now works as an algae consultant.

Part of the problem that arises is that there is not always enough scrutiny given to the ideas that are proposed, where fancy computer created pictures of possible future plants hide the reality of the thinness of the ideas and the lack of comprehension of the scale of the difficulties that must be overcome in a number of different fields, if the technology is to come to fruition. The article continues:

Whether the algae charlatans will be exposed before the DOE sinks taxpayers' money into their companies is another question. Curtis Rich, a renewable energy attorney, says he believes the DOE's review teams will be "able to determine those projects based on press releases and those based on sound research." But Benemann is not so sure. The week GreenFuel folded, the DOE awarded an Arizona utility $70.6 million to scale up the firm's technology.

Outside of the major efforts that are being carried out, there are also a considerable number now of smaller programs that Universities such as ours are getting into, to further explore the technology. Algae have benefits not only from the oil that some varieties can form in sufficient volume to appear attractive, but also because they can adsorb significant quantities of carbon dioxide as a part of that photosynthetic process. Thus there is a potential for their use in reducing the carbon dioxide output from power plants and other gas producers. Often these experiments don’t get a lot of light, but occasionally even efforts such as ours catch a little attention.

There are some successes that have been reported on some of the subsidiary problems that have to be overcome on the way to generating a sufficient volume of oil to be realistically useful. These include ideas that relate to harvesting and separation of the different constituents of the mix. However, one of the difficulties in writing about a subject that is part of my day job, is that some of the more interesting current work cannot, at this stage, be published – for a variety of reasons – some obvious.

So let me stop before I get into too much trouble and merely note that the technology has already shown promise and some answers, but that I do not believe that it will provide the rapid response to the developing peak in oil production in sufficient time to have any impact on that situation.

Cost viability and algae

Robert Rapier recently drew attention to the demise of GreenFuel Technologies, the company founded on ideas from MIT and Harvard and supported by millions of dollars in venture capital funding. One of the creative ideas that the company has was to located their plant at existing power stations so that the carbon dioxide generated in the flue gas could be fed into the bio-reactors holding the algae, with the gas also keeping the algae at an optimal growing temperature. It was a company that was in the vanguard of promoting the use of algae in both carbon dioxide collection and liquid fuels production.
The company, however, ran into problems in raising more money in the current climate, and with the technology.

Getting the whole thing to run smoothly, though, was tougher than expected. GreenFuel could grow algae. The problem was controlling it. In 2007, a project to grow algae in an Arizona greenhouse went awry when the algae grew faster than they could be harvested and died off. The company also found its system would cost more than twice its target.

It is that latter part of the paragraph that is the more telling. When folk first consider using algae as a future fuel source, it is often because, when tabulated, algae can produce more fuel per acre per year, than any other crop.

(Source Biodiesel - Growing a New Energy Economy - Greg Paul, Chelsea Green Publishing Company, 2005, 281 pages)
However, getting what has been achieved in the short term, into a production mode that sustains the same yield for year after year is not that easy. Nor is simply finding the best algae the only solution required for the problem.
Given the collapse of GreenFuel, it is perhaps useful to look at some of the things that need to be considered, if you are going to have a shot at a viable algae operation.

First you need to select an algal species. This is not as simple as it sounds, because the initial thought might be to screen all the thousands of algae types that exist around the world to find the ones that (a) hold the most oil and (b) grow fastest. Algae grow by multiplication and so the common metric for the latter is the time it takes to double the volume of algae in a container, with less than a day being a good place to start. And a species that has 50% lipid content (the oil component) is also the sort of ballpark we are looking for. There are a number of candidates that meet (or come close to meeting) these criteria. One of the benefits of the program that the NREL review of algae produced was a filter of the thousands of candidates, that gave data from which to select some of the more productive.

Let us, for the sake of discussion, call one candidate AA, another BB, and a third CC. One of the early things you discover is that some of the better ones grow in salt water (seawater) rather than in river/lake conditions. That makes a little difference, particularly if you are interested in putting your algae operation (we’ll call it a farm) out in the middle of the country many miles from an ocean. So that if you need that water you can either make it or import it, neither cheap.

And speaking of cheap, one of the first steps is to decide how you’re going to contain your algae and growing medium (nutrient). GreenFuels used plastic tubes, but as Fireangel pointed out over at The Oil Drum these are very expensive and he concluded

That leaves gross profit of $3.00. That means at current prices it would take 50 years to just cut even on their investment. That is clearly not feasible. For one thing these polycarbonate sheets take a lot of UV damage and their useful life is almost always less than 15 years (usually 10 years).

It seems that at a recent algal biofuels meeting it was concluded that the large flat race-track type of layout is the only one that stands the chance of financial viability.

But that selection brings its own concerns. For the light to reach the algae throughout the water column in adequate quantity, the water can only be around 6-inches deep. This means that the ponds have to be large, (bringing in construction and other land costs). It also limits the species that can be grown, since the conditions are more tempered by local conditions and survivability. This almost mandates, for open systems, that the local conditions select the algae, rather than picking the best. (Which helps explain why we chose a confinement strategy based on facilities constructed for other purposes and paid for, but that is another story).

So having selected the algae and the farm, the next cost is for the nutrient that the algae needs, and to supply the carbon dioxide. Here the potential for beneficial selections should be considered, some algae for example can use sewage as the nutrient, and if cap and trade comes along, then some of the income can come from the carbon captured and used by the algae. (Proper distribution of the gas, and keeping the right quality and concentration also costs, as may the supply and its transport)

Having grown the algae, the next step is to harvest it and separate out the algae. There are some interesting new concepts (bearing in mind that the algae are a very small percentage of the pond volume).

One way of reducing the costs of separation by using an algae, such as botryoccocus, that weeps oil rather than creating it internally.

Another, Phycal, is trying to harvest oil from algae without killing the algae. Instead, Phycal bathes the algae in solvents which can suck out the oil. Some strains of algae can go through the process four times or more.

There seem to be two snags to the process, the first being that the algal productivity seems to decline with cycle number, and the other is that the biomass itself, once the oil is removed, may have value.

Costs from Solix for example:

Algae biofuel startup Solix, for instance, can produce biofuel from algae right now, but it costs about $32.81 a gallon, said Bryan Wilson, a co-founder of the company and a professor at Colorado State University. The production cost is high because of the energy required to circulate gases and other materials inside the photo bioreactors where the algae grow. It also takes energy to dry out the biomass, and Solix uses far less water than other companies (see Cutting the Cost of Making Algae by 90%).By exploiting waste heat at adjacent utilities (one of our favorite forms of energy around here), the price can probably be brought down to $5.50 a gallon (see Will Waste Heat Be Bigger Than Solar?). By selling the proteins and other byproducts from the algae for pet food, the price can be brought to $3.50 a gallon in the near term.

OriginOil noting that

“The energy cost of extracting algae is 10 times the energy cost ofextracting soybean oil,” Riggs Eckelberry, CEO said.

has a video on their site showing a cheaper way of getting the oil out.

The process also generates glycerin and oxygen as byproducts that could be collected and become part of the saleable product.

Alternately the algae can be used to generate natural gas ) as suggested by Genifuel

It works like this. Algae is grown in ponds and, while it is still wet, is it placed in gasifiers with a chemical catalyst that allows it to cook at relatively low pressures and temperatures, said president Jim Oyler. It cooks at 350 Celsius versus 700 Celsius.

The cooking produces a synthetic gas that is 65 percent methane, or CH4, and 35 percent carbon dioxide along with some other trace materials. The carbon dioxide is then pumped into algae ponds as food. It will be more expensive than natural gas pulled from the earth, but it will require lower subsidies than liquid algae fuel to be competitive with its fossil fuel equivalent. It yields 0.55 liters of gas per gram of dry material, Oyler claimed.

There are thus a lot of considerations (I really did not get into efficient light use, correct fluid temperatures, and secondary processing) which led to the conclusion some time ago that this has to be addressed as a system problem, and set of solutions, rather than piecemeal. Profits and income streams from as many sources as possible have to be included, since without them, as with GreenFuels, the concept is not enough to be sustainable. And to develop the systems approach needs a lot of different inputs.