POINTS OF VIEW

FOREST ENERGY or WOOD ENERGY?

Below are some of the comments we have received on this theme, which we launched in FEF 4 and FEF 5. The first is in answer to Mr Hulscher's comments on this subject in FEF 4 and Mr Hulscher's reply.

I have been wanting to write to you for quite some time. I am reading Forest Energy Forum No. 4 and am finding it difficult to resist.

I found the "Forest Energy or Wood Energy?" Points of View quite interesting. I consider both of them are quite different in the context of Asia, especially in the Indian context. At the same time I feel that the statement, "most of the wood energy comes from non-forest land" is also not very true. In fact, both issues are interrelated and are directly governed by the closeness to or distance from the forest, socio-economic status of the family and, occasionally, by the family size also.

I must accept that I do not have any primary data at this stage. In fact, I was thinking of writing to you for a small research grant for 12 months to conduct a study on this theme. (Dr Rekha Singha, Indian Institute of Forest Management, Bhopal, India)

Mr Hulscher's reply:
"Not all fish comes from the sea, not all chilies come from Chile, and not all woodfuels come from forests." This is a quotation from RWEDP's Regional Study on Wood Energy Today and Tomorrow in Asia (published in 1997 as Field Document No. 50). Many foresters are not yet aware of the primary data which show that typically two thirds of all woodfuels in Asia come from non-forest land. For India such data have been available at least since 1985, the year when the National Council of Applied Economic Research (NCAER, I. Natarajan) published a study entitled "Domestic fuel survey with special reference to kerosine". This was summarized in the famous book by Gerald Leach, Household energy in South Asia (Elsevier Applied Science, 1987). For instance, the data show that in both rural and urban areas in India more fuelwood is collected from roadsides alone than from forest land. In fact, from all fuelwood collected in 1978-79 (close to 69 million tonnes) only 35 percent comes from the forests, and the balance from non-forest land.

I should also refer to RWEDP's Field Document No. 37b, page 31, published in 1993, for an overview of data. The more recent data from India are based on a publication by the Forest Survey of India (FSI) of the Ministry of Environment and Forests, Fuelwood, timber and fodder from forests of India (1996). This report shows that out of 172.5 million tonnes of woodfuel in 1991, 70.5 million tonnes came from forests, which is equivalent to 41 percent. The actual share will be less, because scrap wood as a source of fuelwood had been ignored. An important and related issue is the following quotation from N.H. Ravindranath and D.O. Hall: "All the available evidence shows that the rural fuelwood requirement does not seem to lead to deforestation", (in Biomass, energy and environment: a developing country perspective from India (Oxford University Press, 1995).

Woodfuel is a legitimate product from forest land, and even more so from other land. A highly interesting study by N.C. Saxena, The woodfuel scenario and policy issues in India, was published by RWEDP in 1997 as Field Document No. 49. Woodfuel is also an important product; RWEDP has estimated that the annual economic value of woodfuel in India is equivalent to about US$10 billion. Further studies on non-forest land as sources of wood are currently being undertaken by the FSI. I would suggest that scholars interested in the subject contact FSI and/or NCAER, in order to avoid duplication of efforts. (Wim Hulscher, RWEDP, Bangkok, Thailand)

I would like to respond to the definitions given for "Forest Energy" and "Wood Energy".

I am an electrical engineer and have an interest in learning and getting information related to energy from biomass. The purpose of this communication to give my view(s) as far as the above terms are concerned. I think that for a clear and precise definition of the two terms, and to figure out the difference between them, it is necessary to examine the three key words: "Forest", "Wood" and "Energy". The simple scientific definition of energy (the ability to accomplish work). For definitions of Forest and Wood, you can help me there.

The point that I would like to make is that wood energy is part of forest energy and not vice versa. From my observations, Forest Energy is a wide subject, which involves all forms of energy from forest. For instance, the food we eat is one form of energy which the body uses. Still, you can get food from the forest.

And when you consider wood energy as the energy obtained from woodfuel, then the forest must not be looked at as the only source for this. Other sources include bush and shrubs (I think these might not only be part of the forest), stem remaining from some plants, e.g. cassava, sorghum, maize (this is very common in my country - Uganda) and others. (Al-Mas Sendegeya, c/o University of Oldenburg, Germany)

Raising the profile of household energy

The last issue of Forest Energy Forum (FEF 5) had an interesting article on household energy including health issues written by Dr Grant Ballard-Tremeer with comments provided by Miguel Trossero. Although at first sight their views seem opposed, some further "investigations" show that both may have a point.

The global burden of disease (Murray and Lopez, 1996) provides an overview of various burdens of diseases from environmental causes measured as Disability Adjusted Life Years or DALYs. This overview shows that there are considerable variations depending upon area. While inadequate water supply and problems with sanitation are the largest threat to human health in almost all regions, indoor air pollution is the second largest factor which affects human health in most areas with the exception of Latin America (including Argentina), the former socialist economies of Europe and the established market economies.

Although biomass energy use is certainly not the only source of indoor air pollutants, at the same time there is no doubt that it is an important factor that affects indoor air quality. Efforts to alleviate the impact of biomass energy combustion on indoor air quality should therefore receive sufficient attention. In fact, it should be considered as important as addressing fuelwood shortages, etc. This is also evident from work on a new World Bank Environmental Strategy which indicates that critical environmental health issues should be integrated in the operations of relevant sectors. This work cites as one of the examples the need for integration of indoor air pollution in energy operations (Lvovsky, 1999).

At the same time all this does not imply that the sustainable use of biomass as a source of energy is not good or should not be supported. It is rather that conversion equipment like stoves and furnaces need to be improved.

References
Murray, C.J.L. and Lopez, A.D., eds. 1996. The global burden of disease. A comprehensive assessment of mortality and disability from diseases, injuries and risk factors in 1990 and projected to 2020. Harvard School of Public Health, Harvard University Press.

Lvovsky, K. 1999. Health and Environment in Environment Matters 1999. Annual Review July 1998-June 1999. Environment Department, World Bank.

(Auke Koopmans, Wood Energy Conservation Specialist, FAO-Regional Wood Energy Development Programme, Maliwan Mansion, 39 Phra Atit Road, Bangkok 10200, Thailand; fax +66 2 280 0760; E-mail [email protected] ; www.rwedp.org ).

Experiences as a volunteer

I started my assignment as a volunteer in the Swedish Volunteer Programme with FAO's Wood and Non-Wood Products Utilization Branch (FOPW), on 23 November 1999 and finished on 15 March 2000. During that period I worked in the Wood Energy Programme under the supervision of Miguel A. Trossero.

The aim of the Swedish Volunteer Programme is to promote the recruitment of young Swedish female academics in international organizations, such as FAO. With the contacts that I made during my work as a volunteer, I have now been recruited as a consultant in the Research and Technology Development Service (SDRR) of FAO's Department for Sustainable Development.

My main activities were to revise the existing wood energy statistics and collect information and data from bibliographic and statistical sources at international and regional agencies, in addition to national figures when available, on the utilization, production, export and import of wood for energy purposes in the Near East countries, which amounted to 28 countries. The resulting data were presented using the Unified Wood Energy Terminology (UWET) framework, definitions and factors. Similar regional studies have previously been carried out on wood energy use in OECD-countries, Latin America and the Caribbean, Asia and Africa.

I also assisted in other activities such as bibliographic research on "the contribution of forest products for the mitigation of climate change".

I found the work of the division challenging and stimulating and as such it has provided me with valuable and important work experience in an inspiring multicultural working environment. I was included in the activities of the Wood Energy Programme, giving me a significant insight into the work done. I am grateful for the great warmth that I received from all the colleagues in the division and I appreciate all their help with the necessary practical arrangements. Thank you all. (Hazme Akyol)

Charcoal

Charcoal has many drawbacks - but it has been the principal fuel of humans for 20 000 years and we have learned to work around these disadvantages.

Making wood into charcoal typically gives yields of 30 percent in industrial processes and 15-20 percent in developing countries where it is still one of the few simple fuel options. Thus, 70 to 80 percent of the wood's energy is wasted in simple charcoal manufacture.

Professor Mike Antal at the University of Hawaii has developed a process for making a 45 percent yield charcoal from wood. I hope he will take this opportunity to give us all an overview of where that stands now. What fraction of the original wood energy is captured?

Charcoal is a necessary product of wood pyrolysis and pyrolysis is a necessary step in wood gasification and combustion. By properly gasifying the charcoal intermediate during gasification, it is possible to make very low tar and ash producer gas, so we in gasification need to pay attention to the charcoal. (Source: Tom Reed, Stoves network E-mail list, [email protected] )

Charcoal gasifier

The following exchange from the gasification E-mail list expresses an interesting point of view.

... I was considering a micro scale, in the absence of an electricity grid with cooking taking place on "idd" woodstoves (essentially small hybrid pyrolyser/gasifiers with a large char residue) the char being utilized in cheap small gasifiers with no (or small) problems of gas cleanup in standard spark ignition engines to produce power. (AJH)

I think this is worth a closer look. Let's start with all our usual optimistic assumptions about fuel, technology and sociology. In a mythical village of 100 people where each household cooked with a pyrolyser stove and produced 0.5 kg of charcoal, at roughly 60 percent of the fuel value of gasoline. If the charcoal gasifier was 60 percent efficient, our village might accumulate the equivalent of 18 kg of gasoline, or roughly 25 litres per day.

It is easy to produce charcoal from the "right" fuel, while producing useful heat and low emissions. Check out www.ikweb.com/enuff/public_html/Turbo/Turbo.htm for one example of a pyrolyser/charcoal-making stove and www.ikweb.com/enuff/public_html/aburner/td1.htm for a recent experiment of mine, based on the same principle.

Perhaps someone could tell us how much simpler it is to make a charcoal gasifier than a wood gasifier for a spark ignition engine?

Let's try and compare this example with, say, that of a diesel unit running on Jatropha oil. Aside from electrical generation, why not use the torque to grind grain? For Jatropha, an hour spent pressing oil can save many hours grinding grain. Can an hour spent resizing fuel for a pyrolyser stove save as many grinding grain?

Current and forecasted oil prices should provide the necessary "spark" to reignite the gasification and biodeisel folks into action. (Alex English, RR 2 Odessa, Ontario, Canada K0H 2H0; fax: +1 613 386 1211; E-mail: [email protected])

(Source: gasification list [ [email protected] ])

Noah built his ark before the flood. Today we need to build an ark by planting trees and other energy crops and constructing the facilities needed to produce solid and liquid fuels from them before the oil needed to do so runs out. If we wait it will be too late!

(Source: Thomas J. Stubbing, HEDON E-mail list)

The classic wood-burning cookstove

The more I mess around with stoves the more I am impressed with the importance of really dry fuelwood. If you let it age for two years the fires will be hot, smoking will be greatly reduced and problems with creosote lessened as well. How you use the stove is very probably more important than what kind of stove you use.

We try to cut the fuelwood into smaller split pieces of kindling and feed them into the fire more frequently. If you meter the fuel there is almost no smoke. When you throw a big cold log on the fire smoke starts to pour out of the chimney until the combustion chamber can climb back up to 500�C and burn up the harder-to-combust gases such as methane.

In my opinion, a well-insulated house, with less than one air exchange per hour (being tight is more important than the super insulation, air leakage really loses BTUs) does not need a heavy stove. Get the house warm and it stays warm. Insulation and diminished air exchange takes the place of thermal mass. Either extends the length of time the house will stay hot. Insulation works better, I think.

Burn the wood hot, meter the fuel, keep exit temperatures below 150�C. An old cooking stove can do that quite well. (Source: from a comment by Dean Still on the Stoves List, [email protected] )

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