Gasoline From Grass

Biofuel Grassoline – Gasoline From Grass
Gioietta Kuo
Augusr 8 2009
Senior Fellow, American Center for International Policy Studies  amcips.org

It present 25% of world energy is  consumed by transport  using mostly oil.  As oil is on the wane, new echnologies are appearing both in the kind of motor car we drive and the fuel we use.

It is true to say that most technologies  are  market driven, which in turn is determined by demand.  However, there are pitfalls in rushing headlong into  production with a  certain technology without some cool headed  long term analysis of the viability and  basic contradictions that might exist in the route  taken by the market.    For example the market may change or new technology may become available,  so that the production just initiated  becomes short lived  with the result that the capital put into production  cannot be recovered.

A good example of just this phenomenon is the rush into first generation biofuel over the last several years.  In other words the world’s rush into production of ethanol from corn and soya  beans in the US  and sugarcane in Brazil.    In many respects this has been regrettable,  not to say a  mistake for it has done  the world some harm.   It is understandable how it all came about.   Given the sharp rise in oil prices, producing  ethanol may provide a cheaper transport fuel.   It was also driven by  the Bush Administration’s wish to be independent of foreign oil, thus farmers  were given huge government subsidies to produce  ethanol from corn.   Already there are 180 refineries processing corn into ethanol using around 30 % of US corn production in the US.    However, even if all the corn produced by US is processed into ethanol, it would satisfy only 20% of US transport needs,

What is a grave  mistake is that food stuff : corn and soya bean in the US and sugarcane in Brazil are processed for ethanol  for transport and thereby the world’s energy market became tied to the food market.  As a consequence,  grain prices on the world market shot up by 50% or more in 2007,  causing hardship and hunger for the poor in countries which import US corn like Mexico, China, India and parts of Africa.  It may be laudable that Brazil has become independent  of foreign oil by using  sugar produced ethanol.  However it has come about at the expense of cutting down Amazon forests to produce arable land to grow sugarcane.  Environmentally this is very undesirable.

It is obvious that we cannot go on using food to produce oil since the world’s demand for food  is insatiable as the world’s population soars.  It is logical to decouple food from energy which means discard first generation biofuel.     Instead we should use second generation cellulosic biofuel,  which is liquid  fuels made from dozens of sources.  Basically   this consists of inedible parts of plants:  agricultural leftovers like wood, sawdust  corn stalk, wheat straw,   Then there are specially grown   ‘energy  crops’  – fast growing  grasses like  switchgrass.  Basically the oil derived from this cellulosic material is what  we call ‘grassoline’.

The advantages of this second generation biofuel are that the feedstocks are cheap : about $10 -$40 per barrel of oil energy equivalent, abundant and independent of foreign sources.   Most important of all,  it does not interfere with food production.  Most of these cellulosic material can be salvaged from plant wastes.  Energy crops can be grown on marginal lands which would not otherwise be used as farmland.

Annually 1.3 billion dry tons of cellulosic biomass can be harvested  in the US without interfering with the food chain.  Globally, there is enough cellulosic biomass with an energy content equivalent to between 34 to 160 billion  barrels of oil a year, exceeding  the world’s consumption of  30 billion barrels of oil.

Now for the difficult part.   While  fermenting corn kernels is relatively easy,  breaking down tough stalks of cellulose is hard.  Nature has made cellulose the backbone of plants to  support  the plant’s vertical growth.  It is rigid and very difficult to decompose.  Cellulose is made up  of thousands of glucose molecules strung together.  To release the chemical energy inside these sugars, one must untangle the molecular knot that make the cellulose beams.

There are numerous ways scientists are developing the technology to break down the interlocking molecules.  Basically they consist of  deconstructing the solid biomass into smaller molecules by heat, acids or bases,  choosing a method that will most likely be commercially competitive with petroleum.

One method (AFEX) cooks cellulose at 100 degree C with concentrated ammonia under pressure. Enzymes then convert the cellulose into sugar which then turns to ethanol.   AFEX has the potential to be very cheap : approximately $1 per gallon of equivalent gasoline energy content, could be selling for $2 at the pump.

Technology is progressing at a furious pace.  A stimulus bill from US government signed this year provides $800 million funding for the Biomass program as well as $6 billion loan guarantees for ‘leading edge biofuel projects’.   So a number of demonstration plants are already on line and first commercial biorefinery projects will commence  construction by Oct 2011.    But the technology will take 5 to 15  years to be on the market.

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