Ethanol to Hydrogen, A Double Duty Fuel

What a load of BioMass!!! If you go to the trouble of making ethanol, why urinate away the gain in a wasteful proccess of making hydrogen????

The growing of crops to produce either EtOH or biodiesel for U.S. transportation needs is not rational. Subsequent conversion to hydrogen would only compound the error. Using the most generous assumptions, i.e., * 150 bushels of corn/acre * 2.8 gallons of EtOH per bushel * 0.67 energy ratio relative to gasoline A fossil fuel-based (petroleum and natural gas inputs) ethanol economy would produce the equivalent energy of 122.4E9 gallons/year of gasoline if all the arable land in the United States were used to grow corn. A biodiesel system would be substantially worse. As of October 8, 2004, U.S. gasoline consumption was 137E9 gallons/year. However, in the absence of any significant supplies of petroleum and natural gas (circa 2100), a self-supporting ethanol system would require about 11 times the arable land in the U.S., or more than twice the total land area of the nation. Biomass-based energy would be a waste of land and resources. The current subsidies for corn and ethanol mask the realities.

Agreed Russ. A biomass system can at best only meet 10 -15% of present demand unless some breakthrough in algal biodiesel etc. occurs. It is better to use more efficient solar technologies like photovoltaics, thermal electric, wind, hydro etc.

However, a biomass system could only meet a fraction of our demand if it were fuelled by fossil energy. The net energy would be insignificant. Biomass energy is a non-starter without fossil energy and material inputs. By 2050, U.S. per capita petroleum supply could be less than half the present leve. Note that corn yields per unit area could drop by a factor of 2-3 without the fertilizers that are synthesized (Haber process) from natural gas and atmospheric nitrogen at high temperature and pressure. The feedback loops in this system are killers.

Typo: line 5 should read "present level"

If I was looking in a rear view mirror I would agree with Russ and Sheldon. But those of us who are looking ahead have identified 20-30 different technologies with capabilities to make biofuels out of number of biomass resources including agriculture and forestry crops and residues, rights of way, forest, yard and garden trimmings, the biomass fraction of municipal wastes, human and animal wastes -- and if we run short then, we can turn to aquatic biomass. In terms of fertilizers to grow the crops and trees, we can produce biobased fertilizers as part of the process of producing biofuels from wastes. Russ and Sheldon, keep looking in the rear view mirror, 10 years from now you will see 40 billion gallon/yr biofuels production capacity -- ethanol, biomethanol, other alcohols, biodiesel, biooils and biohydrogen. And, by the way, we will be contributing to national, energy and homeland security, creating thousands of new basic industries and millions of quality jobs, reducing fossil fuel pollution and improving public health, and making major contributions to greenhouse gas stabilization. If you want somebody to ride with you, invite David Pimentel from Cornel. By the way, be sure you fuel up on biofuels during your next stop – we need the business.

Question--the net energy ration on biodiesel is more favorable than ethanol--why would it be worse? Comments on the mismatch between biomass production and our fuel appetites are correct. But for reasons relating to our climate, we need carbon neutral strategies. We will have to reduce our consumption of whatever energy source to match the solar generation rate (or we will be forced to do it) but once we do, the option of biofuels becomes clearer. And as the last post notes, we won't be talking about any one source, but rather a medley of sources. One size fits all is a thing of the past.

Looking ahead is a fine thing to do, if done well. That requires consideration of the amounts of energy that will be needed and the amount of energy, materials, and land required to produce them. Until all these variables are evaluated, the fact that we convert crops, residues, trimmings, wastes, and algae in eutrophic ponds into energy is little more than marketing and promotion. If such systems cannot meet demands without the energy and materials provided by petroleum and natural gas resources, they are useless. The United States does not have enough arable land to produce enough of any one of the proposed biomass energy crops, or any combination of them. Absent fossil resource inputs, a self-sustaining corn-ethanol system would require 11 times the amount of arable land in the U.S., or more than double the total U.S. land area. By any standard of judgment (and choice of "mirrors"), this would appear to be a rather significant constraint. As for the favorable biodiesel energy ratio, the oft-cited energy and mass balance did not consider the requisite "feedback" amounts and net production rate for a self-sustaining system. Biodiesel would require even more land than that of the corn-ethanol system. Naturally, the use of all arable land to produce a small fraction of our energy needs would tend to diminish our food supply. Eventually, the concomitant population reduction by mass starvation could drive the entire system to a new equilibrium state. For a "forward" look at future energy supply, not including biomass, consider the first two papers in the published proceedings of the NEA/OECD meeting of October 2003 (NEA No. 5308).

Russ, et al, I'm sticking by my guns. We don't need to put more crop land into the production of biofuels feedstocks -- its the waste streams and the enormous amount of land that can be put into the production of trees that we need to tap. We could also plant and harvest biomass feedstocks on CRP lands in a manner that would increase the organic matter in the soils of these protected lands. Don't think crops; think all kinds of biomass and organic waste streams and trees. Ride the train from Boston to Richmond and look at all the wasted land that would look much better with well cared for and periodically harvested coppicing trees. Take a similar ride in Europe and take note. Hike a power line rights-of-way, and think of all the trees that could be grown, managed and harvested, think of the wildlife habitat -- all of which could be managed, and would save the utilities money if it was done right. Think or the CO2 that could be sequestered. Today, a good portion of biodiesel is made from used cooking oil, yellow and trap grease. Tree oils are another source of biodiesel feedstocks. In terms of studies -- when we launched the ethanol and biodiesel industries, we did not study much of anything. We just did it, and it worked. Look at those red states and evaluate the political support that is available for biofuels. Of course we have to be smart, but some smart guys should quantify all the externality costs that keep us hooked to fossil fuel pipelines. We could then evaluate the comparative merits of biofuels versus fossil fuels. Read the National Defense Foundation Study on this issue for starters. Of course we need all the options in play now, as well as a wise and cost effective process to transition, over the next 20-50 years, from a fossil to a renewable energy economy. Think of your kids and my grandchildren/great grandchildren, and don't forget greenhouse gases and the 2 to 3 billion citizens that don't have the needed calories, electrons and Btu to meet their basic needs in a modern world. We have now, or will soon have, all the technologies to meet the basic needs of those folks and the environmental needs of this planet. Watch our smoke (not our tailpipes, ain’t no smoke there). If you would like a copy of our draft National Security Action Plan, send me an email -- biorefiner@aol.com. Would appreciate your comments and edits. We not-so-smart guys need all the help we can get.