Friday, February 21, 2014

Another Kind of Energy or ComPost-Modernism

PERMACULTURE HAS ITS GENESIS in the visionary work of J. Russell Smith, J. Sholto Douglas, Robert Hart, and others less well known, who, two generations ago and more, realized the urgency of transforming the basis of agricul­ture through the use of trees and other perennial crops. They saw the progressive devastation of land that followed the plow and knew that only by integrating forestry and farming could man's impact on the Earth be tempered and hope for humanity's future be secured into the next century.

Following the revelations of ecologist H. T. Odum (I) on the problem of energy, a third leg was added to this vital synthesis as David Holmgren so trenchantly expounds in his essay Energy and Permaculture (2). It was for Holmgren, a young student of design at Hobart. Tasmania, and his unlikely mentor, Bill Mollison a bushman turned university professor, to set forth a systematic and practical approach to implementing these new understandings. Permaculture emphasized redesign of the domestic landscape or self-reliance, building the genius of the local and the individual into this triune and revolutionary shift.

Though widely accepted by both traditional and post-modern peoples around the world, permaculture has been largely ignored by governments and institutions, to which its essential message is anathema. The vacuum of official support has obscured the scope and extent of this revolution in man's relation to the land. It is important therefore, for those of us promoting permaculture concepts and systems to realize that the elaboration of the permaculture design system, though original to Holmgren and Mollison, was neither isolated nor unique, but contemporary with a range of parallel creative work in other western countries.

Rummaging my bookshelf for inspiration on energy in preparation for this issue, I came across evidence for a similar ideation in a slender thesis by Ida and Jean Pain, Another Kind of Garden. First published in 1973 and in a fifth edition by 1979, this little book documents the work and methods of M. Pain with brushwood compost.

A Little-Known Visionary

Pain was a citizen scientist in Occitania, that fabled and historic region in the south of France, whose political fate has long been submerged within the French state, but whose spirit is still restive. Contemporary with Bill Mollison. Pain was concerned with the devastation of the Mediterranean forest by fire, a terminal process of dehumification of soils that began thousands of years ago with the introduction of grazing animals and cereal cropping. He experimented with the production of compost from brushwood thinnings of the garrigue, France's sclerophyllic (dry loving) southern forest. By progressive applications of this compost and careful mulching to retain moisture, Pain demonstrated and recorded in great detail that high quality vegetables could be grown without irrigation in these dry soils. He further speculated that the forest itself could he regenerated by selective use of the same material.

What sets Jean Pain apart from Sir Albert Howard or other advocates of compost for gardening are two important elements, First. Pain placed the source of humic material in the forest and not in agriculture. In this way Pain pointed to a way of making productive the vast scrubland and dry forest regions of the sub-temperate and sub-tropic regions, areas of the planet blessed by abundant sunshine and long occupied by humans, but whose soils were exhausted before the modern age. Second, motivated by a profoundly post-modern understanding of global resource limits, he concerned himself with the production of industrially useful energy from this basic earth resource. In this way he offers a bridge between traditional livelihoods based in shifting cultiva­tion or nomadic herding, and a more modern, prosperous, and settled way of life. He also shows westerners a way out of the dilemma of dependence on fossil fuels.

Why then have we not a better knowledge of this important man and his work? The answers are several and should surprise us little. Jean Pain worked independently in a rural region. He was affiliated with no university or government. Though French is a world language, it is no longer the leading tongue of science and has been eclipsed by English as the lingua franca of cultural innovation. Pain's small, didactic volume was self-published, and its translation into English was awkward, the text difficult to read. Though Pain networked with other researchers in francophone Europe and in California, the extent of his outreach appears to have been limited. He was essentially an agronomic scientist and inventor, without the personality which might have enabled him to publicize and propagate his ideas. And, more broadly, his creative work, like so much innovation in energy technology, was marginalized by the worldwide conservative reaction of the l980's which sought to deny the implica­tions of the oil shocks of the previous decade.

Let's look at Jean Pain's methods and try to assess what sort of legacy he has left us as we enter the 21st century.

Pain lived in Provence and realized the limitations of what Alan Savory (3) has called "brittle environments," those charac­terized by extended seasonal drought. Absent herds of large animals to process the biomass into a form available to soil organisms, organic matter tended to cycle more often through fire than through earth, exaggerating the loss of carbon from soils already depleted and subject to high temperatures for much of the year. While Savory, and his intellectual predecessor Frenchman Andre Voisin, emphasized intensive grazing by herd animals, Pain faced a dry mountainous landscape where resinous plants were dominant. Unsuitable for most grazing animals, the brush-wood, which amounted to as much as 50 ton / hectare (20 ton / acre) was a huge reservoir of volatile fuel for an ever-increasing number of human-caused fires scourging the Mediterranean littoral (seashore).

A modern Prometheus, Pain sought to domesticate this demon for human use. His studies had revealed the essential mystery of humus and its role in soil fertility. The creation of long-chain carbon molecules by a biological alchemy made soils and the environments based on them, more supple, better capable of holding magic substance could be "cultured" by providing supportive conditions for bacteria and fungi to digest plant material: ample mois­ture, controlled atmosphere and temperature and the continuous diffusion of oxygen into the mass were sufficient.

But though the raw material was abundant in the Provencal forests, its collection required chainsaws and motorized transport, and its processing required grinding to increase the surface area and hasten break­down. Collection and grinding required industrial fuels and machinery, albeit simple: trucks, tractors, power saws. How then to close this economic and energy loop? By capturing energy from the composting process.

Alternate Energy Paths

Jean Pain articulates two basic biochemistries: a familar one, that in the presence of oxygen, cellulose and lignins in woody material break down (or build up) to humus; and one less familiar, that suspended in water, anaerobically, and held at 36°C (97°F) the same woody material will support bacteria that produce methane gas. (Only slightly different processes are required to yield wood alcohol, yet a third useful substance.)

Methane--natural gas--is an industrial fuel. It can provide combustion energy for cooking and space heating, but it can also run motors. Convenience in transport and for vehicle use dictates compressing the gas, but this too is possible with methane-generated electricity and simple compressors. The nimble French inventor set out to link all these processes by the necessary technical elements.

Since his first aim was the rejuvenation of the soil, Pain devoted himself first to the perfection of the compost pile. Manual preparation of the material required that it be selected from small branches (less than 8mm thickness) and leafy matter. The presence of chlorophyll (and we know also enzymes and other nutritive substances) enhanced decomposition to humus (4). In the case of industrialized composting a smaller thickness was desired (less than 1mm), with long thin fibers preferable to short thick pieces. He reports that machinery that shaves rather than chips the branches and limbs is preferred.

Obviously, powerful machinery is required to macerate small tree trunks and limbs, and Pain spent considerable attention developing prototypes. One of these, a tractor-driven model, was awarded fourth prize in the 1978 Grenoble Agricultural Fair. The brushwood shavings must then be saturated with water. A cubic meter of woody material will absorb up to 700 liters of water over three days if continuously moistened. Mindful of conserving this precious resource, Pain dug trenches before building his piles in order to drain away excess water which he then pumped hack into the process. A large heap (75 cubic meters, about 50 tons) of this material could be obtained from a hectare of careful forest thinnings (35-40 tons). This would both improve the health of the forest while providing humic manure sufficient to one hectare of cereal cultivation.

Compost piles properly made, of course, heat up. Reaching 60°C (140°F), a heap of this volume would ferment for up to 18 months and provide (through a simple plastic coil embedded in the pile) heated water for domestic use throughout the run of the reaction. Pain reports that he heated his five--room house of 1000 square feet (100 m2) and provided hot water (at a rate of 4 liters! minute) for its occupants from a 50 ton pile for six months, but that a 12 ton pile maintained that output for a full 18 months.

After testing horizontal and vertical coils. Pain concluded that a circular coil or series of concentric circular coils was the best design for extracting heat from a compost consistent with ease of constructing and deconstructing the pile.

Jean Pain continued to refine his technologies. The shredder he devised was later fitted with a recirculating chute for ease of handling the brushwood shavings while obtaining the fineness required. Having proven the utility of heating water (and spaces) with brushwood compost, he experimented with heating air for greenhouses.

And to make a completely honest farmer of himself, Jean Pain insisted on meeting the energy requirements of his harvest and processing machinery, so he turned his attention to the production of gas by methanogenesis. Referring to the work of Ducellier, Isman, John Fry, Sauze, and others, Pain touches only lightly on the technical aspects of gas generation, preferring to report his findings relative to the brushwood source material. Five kilograms of finely shredded brushwood compost yield about 1 cubic meter of methane--about 5,500 kcaI--equivalent to about half a liter of high-grade petrol in energy content. The gas generated by the fermentation of brush-wood requires a simple filtration--which he does not explain but which is presumably referenced in the literature--before it can be compressed and applied to motorized transport (a simple carburetor adjustment for a standard gasoline engine) or electricity generation. As the photos in his book attest, Jean Pain in fact developed or adapted machinery to run from this fuel.

An important development in technique for methane produc­tion was to embed the gas-producing tank (a sealed plastic tub of 4m3 volume) surrounded by coiled plastic pipe, in a Compost heap. The plastic coil conducted water around the gas tank while serving as a heat exchanger. By regulating the flow of water, the temperature of the gas reactor could be regulated to optimize gas production, which in this example was about 1300 liters per day. The now warmed water of course was used for heating the house. Jean Pain connected this supply to a storage reservoir of 36 innertubes. These in turn fed the domestic cooking devices and supplied gas to a compressor run on electricity from a methane ­powered generator. The compressed gas supplied motive power for the farm truck, while the generator also ran lights in the house.

The results are impressive. From a hectare of fire-prone and unproductive forest, 50 tons of agricultural fertilizer can be derived along with the energy equivalent in fluid form, of 4000 liters of high-grade petrol. This energy can he channeled to the harvest and processing of the woody material, and the whole can be accomplished while providing paid employment and a modest profit from the sale of gas and humic manure--by any measure a true permaculture!

Pain calculates the economics of a theoretical 1000 hectare unit managed according to his methods and estimates that process energy required is 12% of energy yield, while counting in all inputs, ores, metallurgy, wood, implements, and so on, 26%; that equipment can be paid for in five years and the financing, including interest, retired within 10. All the while 16 people will be employed at good wages.

Some Caveats

Pain continued innovating and refining his methods through at least 1979 (when the fifth edition of his hook was published). He inspired the creation of a technical center in Belgium (5), and reported pending contact with municipal officials in Seattle, Washington who were interested in applying his methods to process urban wastes. A cooperative enterprise had been formed for the manufacture of brushwood shredding machinery, but interestingly its address has been scratched out from my copy of the book. What has become of him and his work is unknown to me. In the course of 15 years he learned a great deal of the technical requirements of his art, all directed toward increasing the yields and efficiencies of the process, hastening the cycle from cutting of brush to application of compost to soil, recycling material internally (he used aged compost to generate methane, then recycled the residue to soil).

His aim throughout was improvement of forest health. Though I have emphasized in this synopsis the technical aspects of his invention and the industrialization of brushwood compost, Pain himself stresses the importance of sensitive harvesting of the woody material: careful pruning, thinning, and felling are essential to a successful result. In his own words: "This research, then, which was begun in 1964 in the Central Var district and which was aimed primarily at enabling a family of extremely modest means first to get by and then live normally in the forest, has today led to the production of energy in the form of electricity obtained by means of simple techniques, this not being our purpose at the outset."

Pain's work points out the need for further innovation and elaboration of techniques for producing methane and alcohol from woody material. Implied are an array of methane or alcohol-driven motors of various sizes for everything from power tools to generators, transport vehicles, and farm and earthmoving machinery. These are simple fuels, easily derived horn organic materials and thus capable of widespread production and use They are ready substitutes for most of the liquid petroleum-based fuels now used by industrial civilization, and as such arc compatible with a smooth transition away from centrally controlled energy. Though wind and solar will play an important role in a gradual shift of energy sources, there is little promise of either the major revolution in motive technology or of a rapid restructuring of the built environment that would allow us to shift our heavy dependence on transport to these well developed renewable energy sources.

Much interest of late has gone towards the process of converting waste cooking oils into biodiesel. While this is interesting and creative, it seems inherently limited in its applications, primarily because of the relative scarcity of the source material. Nothing like a sufficient quantity of spent cooking fat is available to provide adequate transport energy for the entire population, even at vastly reduced levels of energy use. Also, the production of industrial cooking oils is primarily monocultural and inherently devastating to enormous areas of the planet. Biologically, production of oils requires a more complex and less efficient energy pathway than plant production of cellulose and ligneous material.

There will always be many hundreds, if not thousands of times more woody material than oil produced. In addition to the basic phytochemistry, there is the geographic argument: many millions of acres of land are unsuitable for arable crops, are degraded forest of low yield, or are wastelands wrecked by agriculture­ or toxic chemicals. We need technologies for deriving economic yield from the rehabilitation of these lands. We also need simple technologies to break the monopoly of the fossil fuel industries.

It was the genius of Jean Pain to grasp the essential problem of the age and throw himself into finding simple and appropriate technical solutions for it (even if, by his admission, he did not know all of what he would do at the outset). That these solutions find their most efficient application at a modest and very local scale is a boon to the world and has everything to do with Pain's original intent. The social and labor arrangements, capital financing, and technology­ required to yield useful and commercially valuable energy and fertilizer for individual and community-scale application from restorative forestry are within the reach of large numbers of people and groups throughout the world.

What is needed now is for significant numbers of people to realize and take responsibility for our continued use of liquid fuels in transport, energy for domestic heating and hot water, and to realize that the stable and successful transition to a sustainable economy requires us to develop locally controlled and biological sources for these energies, based on simple, widely available and applicable technologies.

Notes

1. Odum, Howard.T. and Eugene C. Odum. The Energy Basis for Man and Nature. McGraw Hill, 1981.

2. Holmgren, David. "Energy and Permaculture." Permaculture Activist #3 1 May, 1994.

3. Savory, Allan. Holistic Resource Management. Island, 1989.

4. Celine Caron. "Ramial Wood Chips," Permaculture Activist #29/ 30, July, 1993.

5. Jean Pain Committee International, 18, Avenue Princesse Elizabeth, 1030 Brussels, Belgium tel. 32-2241-08-20 or 32-52-30-01-66.

The author admits to no great familiarity with either the production or use of biogas, only a keen interest based on need. He would like to thank Emilia Hazelip for her timely suggestion to investigate the subject, and offers his sincere appreciation to Ida and Jean Pain for their pioneering efforts.

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