Myth: Biomass—plants—can be a major source of liquid fuels
This myth comes up frequently, and it has been rather thoroughly explored through various projects and proven to be a myth. A variety of plants including greasewood in the arid Southwest U.S., sugar cane, sugar beets, trees in general, seaweed, and seeds have been cited as important possible sources of liquid fuel for the future. In 1979, an article in a widely read U.S. magazine states: "Myriad forms of natural organic matter can provide heat or be converted into gas, oil, or alcohol. Wood holds the most immediate promise."(9)
Reality:
In regard to wood as an alternative liquid fuel, a final report on a U.S. government-sponsored project on the conversion of wood to a liquid fuel stated as a conclusion: "Investigations to date have led the authors to be optimistic about the possibilities of oil from biomass. While difficulties in bringing the current facilities on-stream have somewhat limited information to date, it is felt that a vigorous activity in the future can eventually provide a new source of energy for the country in the form of oil from biomass."(6) A translation of this statement might be that "the project didn't turn out very well, but maybe in the future a lot of research could improve results." That may or may not be true. The project involved wood-to-oil conversion, and one conclusion was that "Information gained here should provide the means to be commercially competitive by approximately 1990."(6) The project was abandoned in 1981. No wood anywhere in the world is now being converted to liquid fuel.
There are several reasons why converting growing plants to oil will not be a significant substitute for oil obtained from wells. These have been touched upon in other chapters. Briefly they are:
The energy conversion efficiencies are low, in some cases as with ethanol from corn, it is negative.
The energy cost of harvesting and transporting the materials is high relative to the energy produced. In the case of wood, cutting the trees and loading and hauling them to a processing plant would be energy intensive even before processing into a liquid.
The volumes of plant material available are not sufficient to yield large amounts of oil, given the low energy conversion efficiencies.
The degradation of the land growing these materials by continuing harvesting without returning the fiber to the land is severe.
If wood is considered, there is already a scarcity of wood in most of the world. In the form of wood waste (little is wasted now) there is insufficient raw material from this source to provide significant amounts of feedstock to convert to liquid fuel.
The best land is now under cultivation for much needed human food supplies. If plants were used for raw material for liquid fuel conversion they would either have to displace food crops from present agriculturally developed land, or put marginal lands (thin soil, steep hillsides) into production which would greatly increase land degradation by erosion, and also have serious downstream effects, including silting up of reservoirs.
In final view, the Energy Research Advisory Board of the U.S. Department of Energy stated in 1981 (U.S. population then was 258 million compared with 267 now), that the 258 million Americans used 40 percent more fossil energy than the total amount of solar energy captured each year by all U.S. plant mass. Current annually available biomass volume is no significant replacement for the large storehouse of organic energy accumulated over millions of years in the form of coal and petroleum.
In summary, biomass, at least considering the size of world population today which has to be supported by crops, cannot be diverted from food supplies in significant quantities to be important as a liquid fuel, and at best energy conversion efficiencies from biomass to oil are low. The environmental impact of using biomass for conversion to liquid fuel on a large scale would be severe and unacceptable. Biomass is not a potential source of significant quantities of liquid fuel.
Copyright 1997, Walter L. Youngquist -- Posted with permissionfrom GeoDestinies, by Walter Youngquist PhD & Chair Emeritus,Department of Geology, University of Oregon;National Book Company, 1997; ISBN 0894202995
Reality:
In regard to wood as an alternative liquid fuel, a final report on a U.S. government-sponsored project on the conversion of wood to a liquid fuel stated as a conclusion: "Investigations to date have led the authors to be optimistic about the possibilities of oil from biomass. While difficulties in bringing the current facilities on-stream have somewhat limited information to date, it is felt that a vigorous activity in the future can eventually provide a new source of energy for the country in the form of oil from biomass."(6) A translation of this statement might be that "the project didn't turn out very well, but maybe in the future a lot of research could improve results." That may or may not be true. The project involved wood-to-oil conversion, and one conclusion was that "Information gained here should provide the means to be commercially competitive by approximately 1990."(6) The project was abandoned in 1981. No wood anywhere in the world is now being converted to liquid fuel.
There are several reasons why converting growing plants to oil will not be a significant substitute for oil obtained from wells. These have been touched upon in other chapters. Briefly they are:
The energy conversion efficiencies are low, in some cases as with ethanol from corn, it is negative.
The energy cost of harvesting and transporting the materials is high relative to the energy produced. In the case of wood, cutting the trees and loading and hauling them to a processing plant would be energy intensive even before processing into a liquid.
The volumes of plant material available are not sufficient to yield large amounts of oil, given the low energy conversion efficiencies.
The degradation of the land growing these materials by continuing harvesting without returning the fiber to the land is severe.
If wood is considered, there is already a scarcity of wood in most of the world. In the form of wood waste (little is wasted now) there is insufficient raw material from this source to provide significant amounts of feedstock to convert to liquid fuel.
The best land is now under cultivation for much needed human food supplies. If plants were used for raw material for liquid fuel conversion they would either have to displace food crops from present agriculturally developed land, or put marginal lands (thin soil, steep hillsides) into production which would greatly increase land degradation by erosion, and also have serious downstream effects, including silting up of reservoirs.
In final view, the Energy Research Advisory Board of the U.S. Department of Energy stated in 1981 (U.S. population then was 258 million compared with 267 now), that the 258 million Americans used 40 percent more fossil energy than the total amount of solar energy captured each year by all U.S. plant mass. Current annually available biomass volume is no significant replacement for the large storehouse of organic energy accumulated over millions of years in the form of coal and petroleum.
In summary, biomass, at least considering the size of world population today which has to be supported by crops, cannot be diverted from food supplies in significant quantities to be important as a liquid fuel, and at best energy conversion efficiencies from biomass to oil are low. The environmental impact of using biomass for conversion to liquid fuel on a large scale would be severe and unacceptable. Biomass is not a potential source of significant quantities of liquid fuel.
Copyright 1997, Walter L. Youngquist -- Posted with permissionfrom GeoDestinies, by Walter Youngquist PhD & Chair Emeritus,Department of Geology, University of Oregon;National Book Company, 1997; ISBN 0894202995
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