Next Generation of Liquid Biofuels

At first glance, Canada's liquid biofuels industry would appear to be just in its infancy.  Only a couple of years ago, ethanol and biodiesel production was restricted to a scattering of mostly small-scale plants.  True, recent federal and provincial subsidies and renewable fuel policies have helped kick start the construction of some eight new facilities, capable of easily doubling Canada's production of ethanol and biodiesel.  Still, biofuel production in both Canada and the United States remains but a drop in the bucket compared with conventional gasoline and diesel supplies.

Despite this fledgling status, the biofuels industry is already moving swiftly towards its next generation of production facilities.  And the viable establishment of these new technologies, at commercial levels of production, is not that far away.

"It's no longer a question of technical barriers that have to be overcome," says Richard Adamson, manager of the Southern Research Institute's Carbon-to-Liquids Development Center in North Carolina.  "It's just a matter of proving out these technologies in going from pilot plants to commercial production.  I expect the first commercial facilities in North America will be built within the next 12 months and operational within 18 months."

Moving beyond crop-based feedstocks

The current generation of biofuels facilities, including those still under construction, rely on feedstocks of agricultural crops such as wheat, canola, corn, sugarcane, soybeans and palm oil, as well as animal fats.  In Canada, the primary feedstocks are wheat and corn for ethanol and canola and animal fats for biodiesel.  While they are all quite energy efficient and substantially reduce greenhouse gases - when compared with traditional fossil fuels - they compete, to some extent, with conventional food markets and, in the case of crop-based feedstocks, use only the grain to produce fuel.

The next generation of biofuels will come from a much wider variety of feedstocks, especially those now considered waste products.  These include corn stovers, plant straw, forestry residues, municipal solid wastes and livestock manure.  Specialty energy crops are also being developed such as switchgrass, fast-growing shrubs and trees and even faster-growing algae.  For many of these crops, next-generation technologies will allow nearly the entire plant to be used.  For example, a corn crop could provide both food for humans and livestock as well as stover (leaves and stalks) for ethanol production.

Increased emissions reductions

Next-generation technologies also promise further reductions in greenhouse gas emissions.  According to a European Commission study, ethanol from cellulose could produce 75 per cent less carbon dioxide than regular gasoline, versus 60 per cent less for ethanol from corn or sugar beets.  Biomass-to-liquid biodiesel could produce 90 per cent less emissions than conventional diesel, versus 75 per cent less from conventional biodiesel.

"The next-generation technologies are getting to the point where about the only things coming out of the process are carbon dioxide and ash," says Adamson.  "Everything else is converted to a fuel product."

A third potential benefit is that some specialty grasses and woody feedstocks could be grown in soils too poor and climates too cold to support conventional grain and oilseed crops.  "But a lot of lands are marginal for a reason.  It's hard to get more productivity out of Mother Nature," says Mark Stumborg, section head of Applied Science and Technology Transfer with Agriculture and Agri-Food Canada in Swift Current.  "It's quite possible biomass yields on marginal lands will be low and costs relatively high."

Until recently, the biggest barrier to next-generation biofuels has been developing technologies capable of efficiently and cost effectively breaking down ligno-cellulosic plant materials and converting them into fuels.  In attempting to resolve this problem, research efforts have taken two basic approaches.  The biochemical approach uses enzymes to help convert the cellulose into glucose and then ferments the glucose to produce ethanol.  The biomass-to-liquid, or thermo-chemical, approach - which more and more second-generation biofuels companies are now pursuing - gasifies the feedstock material to produce synthetic gas, which is then cleaned and converted to liquid fuels.

Overcoming technical barriers

Today, many of these technical hurdles are being overcome, at least in the lab and in a growing number of pilot plants.  Ottawa-based Iogen Corporation, for example, has developed a method - combining innovations in pre-treatment, enzyme and fermentation technologies - to economically convert feedstocks like straw and corn stover into cellulosic ethanol, while reducing greenhouse gases by up to 90 per cent from conventional gasoline production.  Iogen has been testing and refining these technologies since 2004 in a development-scale facility in Ottawa and will soon be embarking on a proposed commercial-scale plant, near Prince Albert, Saskatchewan, with an initial production capacity of about 94 million litres of ethanol per year, primarily from wheat straw and perhaps, later, hard woods.  Eventually, Iogen plans to build much larger commercial facilities in Canada, the United States and Europe.

"No one has ever built a commercial plant of that size before," says Jeff Passmore, executive vice president of Iogen, now 50 per cent owned by Royal Dutch Shell.  "There are a number of technical and financial challenges whenever you're commercializing a new technology.  For one thing, we have to integrate all the processes, from pre-treatment to distillation."

Of course, other challenges await the economic arrival of next-generation technologies.  One is building the necessary new infrastructure needed to harvest, transport, store and refine all the biomass feedstocks.  For example, transportation costs - which already account for a large portion of the feedstock price of conventional biofuels - could be somewhat higher, given the bulky nature of most biomass sources.

Improvements in next-generation technologies have brought the price, per litre, of cellulosic ethanol much closer to that of grain ethanol.  In fact, given the soaring price of food crops recently, the initial cost of waste biomass may be somewhat cheaper.  But the cost of building commercial-scale cellulosic plants remains considerably higher.  A 2007 Iowa State University study estimated the capital cost of building a 150-million-gallon cellulosic facility (using advanced Fischer Tropsch technology) could be $854 million, compared with $111 million for a conventional grain ethanol plant of the same size.

Commercial production on the horizon

Still, a growing number of companies, besides Iogen, are preparing to take that final step to commercial production.  Indeed, Range Fuels has already begun construction of North America's first commercial-scale cellulosic ethanol plant, which will use a two-step thermo-chemical process to convert forestry residues, grasses and corn stover into ethanol.  When completed in 2009, the Georgia plant will produce 76 million litres of ethanol and other alcohols per year, with an eventual capacity of 380 million litres per year.  Meanwhile, Vancouver-based Lignol Energy Corp. is teaming up with Suncor Energy to build in Colorado a commercial-sized demonstration facility, which will produce about 10 million litres a year of ethanol from hard and soft woods and agricultural waste.

In June, Toronto-based GreenField Ethanol signed a 25-year agreement with the City of Edmonton to build the world's first industrial-scale facility to produce ethanol from solid waste.  The $70-million plant is expected to initially produce 36 million litres of ethanol per year and reduce carbon dioxide emissions by more than six million tonnes over the project's life.

The City of Edmonton and the Alberta government are contributing $20 million to the project.  That's another sign Canadian governments are backing the transition to next-generation biofuels.  In 2007, the federal government committed $500 million to Sustainable Development Technology Canada towards establishing large-scale demonstration facilities for next-generation biofuels.

More than one technology winner

While various North American companies are pursuing different approaches to producing cellulosic biofuels in commercial quantities, Adamson doesn't expect there to eventually be just one technology winner.  Instead, he sees a number of successful niches being established.  For example, one plant could convert a wide variety of biomass feedstocks into large quantities of biofuels, while a smaller-scale facility might transform nearby sources of just corn stover or wheat straw into ethanol.  And Stumborg foresees small pre-treatment facilities located close to biomass sources as one solution to overcoming high transportation costs.

"I think there will be lots of players and lots of different technologies and successful models in the cellulosic ethanol field.  We expect to be one of them," says Iogen's Passmore.  "People and governments around the world are anxious to see successes in second-generation biofuels."

In the longer term, these next-generation technologies might just be a stepping stone to a whole new generation of biofuels.  Indeed, Adamson says that by as early as 2015, ethanol could begin to be supplanted by "other fuels that are completely synthetic or derived from other sources."  For example, advanced technologies could convert biomass into mixed alcohols - with higher energy content than ethanol - usable by conventional vehicle engines.  And many of tomorrow's plants could be multi-faceted operations, with the biomass converted into not just fuels but also into biochemical products and power for running facilities.

"We're just on the cusp," says Adamson, "of some tremendous changes."