BIO World Congress Cellulosic Ethanol Panel: The Latest on Commercialization Progress

by David Glass (D Glass Associates) One of the morning sessions at the Tenth Annual BIO World Congress on Industrial Biotechnology put four of the companies in the forefront of commercial development of cellulosic ethanol on the same panel. Although friendly rivalries popped up from time to time, what was more striking were the similarities between certain aspects of the technical strategies and business models pursued by these four companies.

The first speaker was Dr. Andre Koltermann from Clariant, who described the company’s SunLiquid® technology which can be used for production of either biofuels or chemicals from cellulosic feedstocks.

The process, which is feedstock-flexible, is claimed to be energy-neutral and nearly carbon neutral (95% reduction in greenhouse gas emissions relative to fossil fuels). It is also distinguished from some of its competitors by the way it integrates the use of enzymes in the process – Clariant uses a small portion of the inputted feedstock to grow the microorganisms that produce the enzymes used by the process, essentially alongside the main ethanol fermentation. Koltermann said that this approach, coupled with optimization of the enzymes for the intended process, yields enzyme costs that are much lower than the company’s competitors.

Clariant has operated a pilot plant with 1 ton ethanol per year capacity since 2009, and in 2012 began operations at a 1,000 ton/year demonstration plant in Straubing, Germany. The demo plant has used both wheat straw and bagasse as the cellulosic feedstock.

Clariant has begun a program of licensing the integrated process in a package which would include the rights to use the entire integrated process technology, including Clariant’s proprietary technology for ethanol separation, along with a supply agreement for the starter microbial cultures not only for ethanol fermentation but also those needed to produce the enzymes key to the process. The company expects to have its first licenses completed this year.

The next speaker was Ghansham Deshpande from Praj Industries Ltd. Praj, a company established in 1984, began pursuing cellulosic ethanol as early as 2006 because of its attractiveness in view of certain features of the fuel market in India and the abundant availability of cellulosic feedstocks in that country. The company has been operating a pilot plant and in 2013 it broke ground on a demonstration plant in India, which it plans to have online in 2014 and fully validated by 2015.

The process includes a highly efficient, low-energy pretreatment step, preparing cellulosic substrates such as bagasse, cane trash, corn stover or corn cobs for fermentation. Praj says it can use enzymes from any vendor, but they have developed a novel reactor design and an improved method for feeding substrate into the reactor, which it says improves efficiency.

The process as currently practiced uses separate fermentations for the C5 and C6 sugars, although a co-fermentation process is under development. The process also utilizes a proprietary method for ethanol recovery, which Deshpande said required low capital and operating expenses. The demonstration plant is located near a sugar mill in Pune, India, and is targeted to have a capacity of 25,000-35,000 liters of ethanol per day.

Oliver May of DSM was the next speaker. After a brief summary of the company’s research activities, much of the talk covered DSM’s cellulosic ethanol joint venture with POET, Project Liberty, which has broken ground on a commercial demonstration plant co-located within POET's Emmetsburg, Iowa biorefinery.

It’s planned that the demo plant would use corncobs, leaves, husk, and some stalk as feedstock, with a capacity of 20-25 million gallons of ethanol per year. DSM contemplates global roll-out for the process during the present decade, including the siting of plants in the U.S., Brazil and Europe.

Much of May’s presentation focused on the areas in which DSM is still innovating to continue to improve the efficiency and economics of the process; in particular striving to improve enzyme performance and the robustness and efficiency of the yeast strains used in the process.

Michele Rubino of Beta Renewables was the final speaker. Describing their PROEA® technology, Rubino stressed that their process is at commercial scale, offers solid, profitable economics, and offers their partners guaranteed performance. Beta has developed this technology with its sister company Chemtex providing engineering support, and in partnership with Novozymes, supplying enzymes and related technology.

The company has been working on cellulosic ethanol since 2006, with a pilot plant coming on line in 2009. Construction began in 2011 on a commercial-scale plant in Crescentino, Italy, which is now operational. The PROESA method uses pretreatment technology that relies only on steam and mechanical treatment, with no added chemicals. The process is designed to be flexible on feedstock, with the plan being to tailor the process to whatever local feedstock is available at each plant site.

The process is first being demonstrated on cellulosic ethanol, but the company is actively exploring its use on other endproducts, such as butanol (working with Gevo) and 1,4-butanediol (working with Genomatica). The targeted cost for ethanol produced from cellulosic feedstocks is less than U.S. $1.50 per gallon ($0.40 per liter). Beta is beginning to offer license packages to the technology, which would include process engineering expertise from Chemtex and the needed enzyme supply from Novozymes. The first license was granted last year to GranBio for a plant in Brazil, and Beta is also planning a project in North Carolina under a USDA loan guarantee.

Together, these talks gave a strong indication that the cellulosic ethanol industry is at last on the verge of producing commercially-relevant quantities of cellulosic fuels, although challenges remain.

What was also striking were the common trends shared by many or all of the four presenters. One that jumped right out is “feedstock flexibility” – a catchphrase that was on the lips of almost every presenter I’ve heard so far at the conference. Particularly for technologies utilizing cellulosic feedstocks, it is essential to have the flexibility to use whatever input material is most readily available, and/or most economical, at any given plant location. While this seems like an obvious strategy, implementing it on a commercial scale poses challenges for both biology and engineering.

Not surprisingly, another common feature of these companies’ business plans were their interests in expanding the process beyond ceullosic ethanol to the production of other bio-based chemicals using cellulosic feedstocks.

Among other common threads were the ongoing efforts to continually improve enzyme performance and the efficiency of the microbial production organism (in most cases being yeast). This is of course triggered by the need to drive the production costs as low as possible, through overall improvements of process efficiency.

It was also striking that at least two of these companies had developed proprietary improvements to the processes for recovering and separating ethanol – although many may assume that established distillation or other separation techniques can suffice for this downstream stage of the process, the reality is that this is a process step that could easily become yield-limiting, and which is ripe for technological improvements that could yield economic benefits.

Finally, it is also interesting that two of the companies (Clariant and Beta Renewables) are pursuing business models that feature licensing, and that they’re both offering complete licensing packages that include enzyme supply and engineering support. This may be an effective way to address global markets without committing major company resources, while also generating revenues in license and consulting fees, and it is a reflection on the complexity of the processes that are being developed.