
                         Roanoke Times
                 Copyright (c) 1995, Landmark Communications, Inc.

DATE: TUESDAY, June 1, 1993                   TAG: 9306010237
SECTION: EDITORIAL                    PAGE: A-6   EDITION: METRO  
SOURCE: RICHARD GODFREY
DATELINE:                                 LENGTH: Medium

LOOK AGAIN AT HEMP AS A PRIMARY FUEL

AT MY ADVANCED age, it's not good for me to read letters such as Edward Spears' critique (May 23, "A good idea goes to pot") of the May 6 letter to the editor by Curtis Douglas ("Marijuana to the rescue of the planet"). When I start laughing, it's hard to stop.

If any of Spears' conclusions could survive close scrutiny, I would have to dispose of half my engineering library as obsolete.

He blissfully assures us that paper-making with a wood-pulp feedstock is not environmentally destructive. He obviously lives upwind, upstream and a long way from a paper mill and from silt-laden streams emerging from clear-cut forests - and that's not a magic wand being waved over the pulp tanks, it's sulfite liquor, old buddy.

Spears blandly asserts you cannot make ethanol from cellulose. Engineering faculties of state universities throughout the South will be astonished and dismayed to hear the revolutionary news. Spears' theory of ethanol production invalidates their research of the past two decades.

If he were capable of distinguishing fact from fantasy, he would know that (a) warm-season grasses, such as switchgrass, big bluestem, Eastern Gamagrass, etc., produce biomass at less than one-third the cost of any kind of grain; and (b) their cellulose, when converted to ethanol, produces more than 400 percent more energy than is consumed in the process.

Contrast this with erosion-causing alcohol from grain, which produces anywhere from a net loss of energy to 20 percent more than is consumed in the process, and it is evident grain alcohol can and will be produced only as long as the present $46 trillion farm-subsidy program continues. When this subsidy declines or vanishes, as it will, if there is any marketplace or military security demand for ethanol, it will be a product of cellulose, not grain.

A steam-acid-catalytic or bacterial reactor is stupid. It doesn't distinguish between cellulose from wood chips, bagasse, grass or Douglas' hemp. Soil, climate and terrain will dictate the most appropriate source of cellulose in any particular locality - somewhat modified by the short-term thinking of farmers who have to cope with mortgage holders who want to be paid annually - not at the 10- to 600-year growth cycles of various tree species.

The problems of burning hemp or more common grasses as primary fuel would not constitute an intellectual challenge to anyone but the sandbox crowd.

Grass briquets are drier and denser than wood, and contain two-thirds the BTU content of an equal volume of coal, and are burned or gasified the same way as coal, without the ashes and with drastically-reduced pollution-control requirements. The Iowa Department of Natural Resources is conducting industrial-scale tests of their use this year.

Richard Godfrey of Catawba is a retired manufacturer.

Memo: ***CORRECTION***

by CNB