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mission:log:2012:02:03:is-burning-wood-bad [2012-03-28 22:31] – [How much is that in trees?] chrono | mission:log:2012:02:03:is-burning-wood-bad [2023-04-19 13:58] (current) – [How much is that in area] chrono | ||
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+ | ====== Is burning wood bad? ====== | ||
+ | So called " | ||
+ | |||
+ | In order to avoid disastrous deforestation, | ||
+ | |||
+ | ===== ===== | ||
+ | |||
+ | To find a more rational answer to this question, the best approach is to look at it from a standpoint of data, trying to assess the past, present and future situation worldwide and make a reasonable distinction between facts and common " | ||
+ | |||
+ | ===== Domestic fuelwood consumption worldwide ===== | ||
+ | |||
+ | Wood used to be the traditional primary energy source of all people for Millenia until the industry nations started to rely heavily on coal, followed by the electrification of households. On the other hand, many " | ||
+ | |||
+ | **Estimations of world fuelwood consumption made during the 1990s (million m³ p.a.)** | ||
+ | |||
+ | ^Source^ | ||
+ | |FAO (1995)| | ||
+ | |FAO (1997) (Scenario 2 - medium economic growth) )| 1.890 | 2.050 | | ||
+ | |Apsey & Reed (1995) (Consumption projection)| | ||
+ | |Zuidema et al. (1997)| | ||
+ | |Nilsson (1996)| | ||
+ | |Brooks et al. (1997) (Lower GDP growth; f. Higher GDP growth)| | ||
+ | |Brooks et al. (1997)| | ||
+ | |||
+ | |||
+ | **Actual & projected fuelwood consumption, | ||
+ | |||
+ | ^ ^ 1970 ^ 1980 ^ 1990 ^ 2000 ^ 2010 ^ 2020 ^ 2030 ^ | ||
+ | |South Asia| 234.5 | 286.6 | 336.4 | 359.9 | 372.5 | 361.5 | 338.6 | | ||
+ | |Southeast Asia| 294.6 | 263.1 | 221.7 | 178.0 | 139.1 | 107.5 | 81.3 | | ||
+ | |East Asia| 293.4 | 311.4 | 282.5 | 224.3 | 186.3 | 155.4 | 127.1 | | ||
+ | |Africa| | ||
+ | |South America| | ||
+ | Source: FAO, 2001 [[http:// | ||
+ | |||
+ | |||
+ | **Actual & projected fuelwood consumption, | ||
+ | |||
+ | ^ ^ 1990 ^ 2005 ^ 2020 ^ 2030 ^ | ||
+ | |Asia| | ||
+ | |- //South Asia// | ||
+ | |- //East Asia// | ||
+ | |Africa| | ||
+ | |South America| | ||
+ | |North & Central America| | ||
+ | |Europe| | ||
+ | |**World**| | ||
+ | Source: MEAD, 2005 | ||
+ | ==== How much is that in trees? ==== | ||
+ | |||
+ | The consumption volume of fuelwood is commonly expressed in cubic meters which allows comfortable comparison to other scientific publications. Unfortunately, | ||
+ | |||
+ | Michael Matuschek, Head of Forest-District 6 in Munich, suggested an average tree, 25m in height and 25cm DWH (Diameter Waist Height) at roughly 1 m³ harvest volume. Using the same data, the DENZIN model, commonly used by forest scientists, estimates the average harvest volume for one tree at 0.63 m³. To keep the estimation as accurate and fair as possible, the factor is averaged evenly (1 tree = 0.815 m³): | ||
+ | |||
+ | **Parameters and formula (DENZIN extended)** | ||
+ | |||
+ | <columns 100%> | ||
+ | |||
+ | * Height in m (h): 25 | ||
+ | * Norm-Height in m (nh): 25 | ||
+ | * Diameter Waist-Height in cm (dwh): 25 | ||
+ | * Volume Correction Percentage (vcp): 3% | ||
+ | |||
+ | < | ||
+ | |||
+ | <m 12> | ||
+ | v = ( {dwh^{2}}/ | ||
+ | </m> | ||
+ | |||
+ | </ | ||
+ | |||
+ | ---- | ||
+ | |||
+ | <columns 100%> | ||
+ | |||
+ | **Average usable wood volume (m³) for one tree** | ||
+ | \\ | ||
+ | \\ | ||
+ | <m 15> | ||
+ | ( {25^{2}}/ | ||
+ | </m> | ||
+ | |||
+ | < | ||
+ | |||
+ | **Number of trees** | ||
+ | \\ | ||
+ | \\ | ||
+ | <m 17> | ||
+ | {1605000000}/ | ||
+ | </m> | ||
+ | |||
+ | </ | ||
+ | |||
+ | <WRAP round important> | ||
+ | ==== How much is that in area ==== | ||
+ | |||
+ | Assuming 1 average tree occupies an area of 20m²: | ||
+ | |||
+ | <m 17> | ||
+ | 1969325153 * 0.000020 km^2 \approx 39386 km^2 | ||
+ | </m> | ||
+ | |||
+ | This is equivalent to the size of Switzerland. | ||
+ | |||
+ | ==== How much is that in people? ==== | ||
+ | |||
+ | **Actual & projected number of people depending on traditional biomass (millions)** | ||
+ | |||
+ | ^ ^ 2004 ^ 2015 ^ 2030 ^ | ||
+ | |Sub-Saharan Africa| | ||
+ | |North Africa| | ||
+ | |India| | ||
+ | |China| | ||
+ | |Indonesia| | ||
+ | |Rest of Asia| 489 | 521 | 561 | | ||
+ | |Brazil| | ||
+ | |Rest of Latin America| | ||
+ | |**Total**| | ||
+ | Source: IEA, 2006 | ||
+ | |||
+ | ==== Analysis ==== | ||
+ | |||
+ | Although newer data indicates, that the consumption levels are lower than the 1990 projections, | ||
+ | |||
+ | ===== Consequences ===== | ||
+ | |||
+ | Because of travelling long distances to collect fuelwood, women and children are often left with limited time for other activities resulting in low agricultural productivity and inadequate time to pursue educational opportunities. Living on the brink of survival also doesn' | ||
+ | |||
+ | {{ : | ||
+ | |||
+ | Right now, while you read this, there are over 2.5 billion people cooking their food on open fires or simple stoves using only wood as primary fuel. And while they have no choice but to burn wood, they also have no technology to help them making the process more efficient. It's easy to say " | ||
+ | |||
+ | {{ : | ||
+ | |||
+ | A fuel-efficient [[lab: | ||
+ | |||
+ | < | ||
+ | |||
+ | ===== Alternatives ===== | ||
+ | |||
+ | Experiments with alternative biomasses like pellets made out of sawdust (byproduct of saw-mills), crop residue, fruit seeds and dung cake to minimize the need to cut down trees even further. | ||
+ | |||
+ | |||
+ | ===== Additional Benefits ===== | ||
+ | |||
+ | {{: | ||
+ | |||
+ | Adding biochar to the soil also increases the water and air holding capacity of the soil, and it promotes the proliferation of mycorrhizal fungi and other beneficial soil microbes. Biochar improves the cation exchange capacity of the soil and prevents nutrients from being washed away. When biochar is incorporated into the soil, we see a 50% to 80% reduction in nitrous oxide emissions, as well as a reduced runoff of phosphorus into surface waters and a reduced leaching of nitrogen into groundwater. | ||
+ | |||
+ | ~~CL~~ | ||
+ | |||
+ | < | ||
+ | ]]</ | ||
+ | |||
+ | ===== Dangers & risks ===== | ||
+ | |||
+ | Use of biomass as primary energy source for households in itself is not a cause for concern. However, when resources are harvested unsustainably and energy conversion technologies are inefficient, | ||
+ | |||
+ | The environmental impacts of inefficient fuelwood use are not really new. Burning wood has contributed to the deforestation of numerous regions of the world. Even at the early stages of industrialization, | ||
+ | |||
+ | One of the biggest risks for the success and good reputation of sustainable biomass energy systems comes from the industry nations: If a considerable amount of primary energy is shifted from oil, coal or gas to biomass, the consequences could be serious. Going " | ||
+ | ===== Conclusion ===== | ||
+ | |||
+ | Burning wood is neither good nor bad. The systematic tendency of " | ||
+ | |||
+ | The goal in biomass fuel and energy conversion research should be to find ways to support households and people in developing nations, who have been traditionally relying on wood as primary energy source and currently have no means to help themselves protecting their health or environment. Simple, cheap and easy to build open-resource hardware like [[lab: | ||
+ | |||
+ | People in industry nations, who statistically need significantly more power per person than developing nations and //choose// to burn wood in an environment, | ||
+ | |||
+ | Burning biomass must not become a simple and cheap way to relieve the political and industrial dependency on oil, coal and gas by firing big industry operated grid-power plants with biomass. | ||
+ | |||
+ | There is also still much potential in wood/ | ||
+ | |||
+ | {{tag> | ||
+ | |||
+ | |||
+ | ~~DISCUSSION~~ |