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| Index_Cambodia |
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| CHAPTER 1. |
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| CHAPTER 2. |
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| CHAPTER 3. |
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| CHAPTER 4. |
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| CHAPTER 5. |
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| CHAPTER 6. |
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| CHAPTER 7. |
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CHAPTER 3. | ||
| Supply Potential of Feedstock/biofuel and Present Status of Utilization | |||
| 3.1 Biomass resources in Cambodia | ||||||||||||||||||
Biomass resources such as wood and agricultural residues are abundant in Cambodia. It is estimated that biomass fuel accounted for some 80% of the national energy consumption (MIME 2001) but biomass fuel used for power generation is limited for a few small-scale projects and negligible amount among the total national power production. Woody biomass accounts for more than 95% of the biomass energy used in the country.
According to our initial survey, rice husk and some other agricultural residues, old rubber wood occurred as the result of new planting and forest wood from plantations and managed natural forests are high potential energy source for electricity generation. The status of those high potential biomass resources is described below: (1) Rice Husk The rice husk is the outer cover of the rice and on average it accounts for 20% of the paddy produced, on weight basis. The average lower heating value of the rice husk is about 13-16 MJ/kg and this is about one-third that of furnace oil, one-half that of good quality coal (Natarajan et al. 1998). Rice is by far the most important staple food of Cambodia. Rice occupies 90% (IRRI and others) of the total agricultural area and is the major agricultural item in terms of area, volume and income. In 2003, rice was cultivated in 2.3 million ha of the field and 4.7 million ton was produced (MAFF 2003). This means nearly 1 million ton of rice husk was produced in the country in 2003. One million ton of rice husk is sufficient fuel for generating 60 MW power (many small scale, 20-100 kW, electricity generation scattered around country) to over 100 MW power (a few large scale, 10-100 MW, electricity generation) for a whole year. 
Prey Veng province produced highest amount of rice, 639,452 t (14%) and followed by Takeo (13%), Kampong Cham (10%), Battanbang (9%) and other twenty provinces (Figure 3.1.1). Only 19% of rice is produced in dry season but those high productive provinces produce fairly good amount even in dry season (27-31% of total production) except Battambang (1%). Rice husk is assumed to be available all year around in most high productive provinces. Prey Veng and Takeo Provinces have also high production per capita basis (0.62 and 0.69 t). Svay Rieng, 6th productive province and produces 7% of national production, produced 0.59 ton per capita which is 4th highest in the country (Figure3.1.1). It can be assumed that the area with high production per capita has better chance for excess rice husk. Generally wood is preferred to rice husk as domestic energy source. Where wood is sufficient it might have more excess rice husk available. Forest cover of top eleven high rice production provinces is below national average of 60% (DFW 2003). Prey Veng and Takeo, the highest two rice production provinces, are the least two forest cover area (2%) but Battambang (4th rice production) province is covered more than 45% by forest and presumed more wood materials are available for energy use. 
International Rice Research Institute reported that about 2.5 million hectare was planted to rice in the 1960s in the country. It declined remarkably during the long continued turbulent history. Both area rice planted and annual production have been dramatically increased in last 10 years (Figure3.1.2). It is expected that rice production continue to increase through expanded area and technical improvement. As results, rice husk production is expected to be increase too. But rice husk is generally utilized well as the main energy source for household cooking and cottage industries such as brick factories. Using rice husk for generating power might affect seriously to energy supply of local communities. On the other hand, some researchers for rural development, agriculture and energy sector or NGO officers told us that there are some excess rice husk in some particular area. We visited a village where 14 rice mills standing nearby in Battambang Province. The village people said there are excess rice husk burned at the field and they want to use it to generate electricity. It is very important to conduct full research for current use of rice husk before introducing electricity generation system using rice husk. It is also worth to conduct survey of excess rice husk of provincial or country level. The COGEN3 program which is funded by European Commission to promote the use of cogeneration in ASEAN countries has conducted a pre-investment study for a potential biomass-fired cogeneration project of 1.5MW electrical capacity at the Angkor Kasekam Roongroeung rice mill just outside Phnom Penh (Williamson 2004). But COGEN3 decided not to invest it at this stage (Williamson personal comm.). Currently there is no electricity generated using rice husk in Cambodia. (2) Cashew Nuts Shell The cashew Anacardium occidentale is a tree in the flowering plant family, Anacardiaceae. Cashew nut is the single seed of the cashew fruit. Cashew nuts trees have been planted 37,140 ha in Cambodia (MAFF 2004) and the number of grower is increasing. They are mainly planted in Kampong Cham province (17,136 ha, 46%), Rotanakiri province (6,505 ha, 18%) and Kampong Thom province (6,371 ha, 17%). Fruits are produced three years after planting. Full production is attained by 10th year and continues to bear about 30 years old. Farmers get R1,500 to 2,000/kg for their sun-dried fruits in Cambodia. Cashew nut shell represents 70% of the fruit total weight, while the remaining 30% is the nut itself. The High Heating Value (HHV) of cashew nut shell is 18.84 MJ/kg (Gaur & Reed 1995) and suitable for direct combustion for producing steam and generating power. The suitability for gasification is not known well. There is no statistical data for cashew nuts production. The average yield of other tropical countries is said to be 800-1,000 kg/ha. The production in Cambodia would be 14,000 t/yr if we apply this figure and nearly 10,000 t of shell is able to be produced annually. But currently most of sun-dried raw nuts are sent across to Vietnam in an informal border trade (Mathew 2003) for processing therefore actual cashew nut shell production would be much lower than the potential. The potential for generating electricity using cashew nuts shells is not high at the moment but installation of electricity generation unit using the shells should be considered when cashew nuts processing factory is planned to be built. (3) Other Agricultural Residues Bagasse is the residue of sugar processing from sugarcane. It represents 30% of total sugarcane weight and its HHV is 15.68 – 19.50 MJ/kg (Graboski & Bain 2002). Direct combustion power generating system has been widely introduced to the sugar processing factory in the major sugar production countries. Cambodia produced 330,649 t of sugarcane in 2003. There is no information about sugar processing factory. The possibility of installation of biomass electricity generation to the factories not only supplying electricity for the factory itself but also for surrounding villages should be assessed. Coconut husks, cassava stems and mulberry stems were tested with the 9 kWe capacity gasification electricity generator at Centre for Livestock and Agriculture Development in Kandal province. Those agricultural residues were all suitable for gasification and their fuel efficiency was 1.3-1.5 kg/kW (Phalla unpublished data). The production of cassava in 2003 was 330,649 t and the area of coconut farm was 27,054 ha. The productions of coconut and cassava residues are not known. The peanut production in 2003 was 18,483 t. Peanuts shells represent approximately 30% of the total weight of the peanuts. The HHV of shell is 18.84 MJ/kg (Gaur & Reed 1995). It can be used for electricity generation if there are large processing factories. (4) Old Rubber Tree There are about 40,000 ha of rubber plantation in Cambodia (JAFTA 1995) and 40,000 t of rubber block, also known as rubber resin crepe rubber, are annually produced, and almost all of them are exported to the countries such as Malaysia, Singapore, and Vietnam (Marubeni Corporation 2004). The rotation period, when the trees are cut down for replanting, is 25-30 years. This suggests that about 3-4% of the planting area is cleared annually and about 180 t of woody biomass are obtained per hectare (Prasertsan & Krukanont 2003). It is estimated that about 25,000 t old rubber trees are harvested annually in Cambodia. Those harvested rubber trees are said to be utilised well as the fuel for brick kilns and household. The excess wood availability is not known well. (5) Woody Biomass from Forests Cambodia’s forest remains generally much better status compare to other Southeast Asian countries. However serious deforestation has been occurring last several decades. In 1960, forests covered 73% of the total land area of the country. It has been decreased to 58% in 1998 (MOE 2002). It is expected to be decreased further to 50–56% in 2010 (FAO 1997). The reduction has been attributed mainly to commercial logging and agricultural encroachment. The 95% of population is dependent on woodfuel for cooking (NIS 1999) and the biomass energy covered 86% of the total national energy supply (ADB 1996). The total fuel wood consumption was estimated about 6 million m3, while log production estimated 1.5 million m3 in 1995 (World Bank and others 1995). Cambodia’s population is increasing rapidly. The annual growth rate is 2.5% (MOE 2002). The fuel wood consumption in 2010 is estimated 40% more to 1995 level (ADB 1996). It is concerned that vast fuel wood consumption might cause further forest destruction. Top et al. (2004) reported that fuel wood consumption to forest biomass increment was only 0.02 in Kampong Thom province and concluded that fuel wood consumption does not cause deforestation. But fuel wood consumption might cause degradation of forest near villages where most fuel wood collection is concentrated. The degradation of high diverse Cambodian forests is the international concern. The increase of flooding in recent years also arrests people’s attention to forest conservation. The fuel wood for biomass electricity generation has to be supplied only from the forest under sustainable management to avoid causing any natural forest degradation. Plantations, tree farming and community forests are the ideal fuel wood resources for biomass power generation. (6) Plantations There are total 11,125 ha of forest plantations mainly with Acacia spp. and Eucalyptus spp. in Cambodia (DFW 2003). The purpose of plantation of most case is production of wood chip materials for export. The selling price for woodchip companies is about $23/t according to DFW. If the plantation wood is supplied for biomass power generation with the same price, the cost is estimated $0.03/kWh and this is about one fourth of the fuel cost of diesel power generation, $0.12/kWh. We have observed the operation of Mear Nork plantation (Figure 5.2.3) in January 2005. The thinned stems and branches were brought to the road and burnt for prevention from forest fire (Figure 5.2.4). Those woody residues are perfectly suitable for electricity generation. There are about 2.5 million ha of grassland and scattered trees area in Cambodia (JAFTA 1995). There are still lots of land available for forest plantations. Using woody biomass of forest plantations has high potential not only for rural electrification but also for main grid electricity supply. 
Figure 3.1.3 Acacia sp. (front) and Eucalyptus camadulensis 3.5 year old stand at Mear Nork forest plantation in Kampong Chhnang Province. 
Source: JICA Study Team Figure 3.1.4 Thinned waste woods were carried to road then burnt for preventin from forest fire at Mear Nork forest plantation in Kampong Chhnang Province. (7) Tree Farming Tree farming of fast growing species is an appropriate method of supplying biomass for village level electrification. Anlong Ta Mei Community Energy Cooperative in Battambang province, the only biomass electricity generation operating in practical manner in Cambodia uses tree farming system for fuel supply. We roughly estimated that 2.5 ha of tree farming is sufficient to supply the average size (140 households) rural villages (estimated using following assumptions; 10 kWh/HH/month and 10 t/ha biomass productivity). The area can be fragmented. Trees can be planted on roadside, at garden edges, in fallow land, with cash crops as agroforestry or any land not suitable for agriculture such as steep slopes. Some legume species such as Cassia spp., Gliricidia spp. and Leucaena spp. are nitrogen fixing trees. They can grow well on the nutrient poor soils and prevent from soil degradation. The two to three centimetre diameter of stems and branches are big enough to be used as fuel therefore harvesting can be started only one year after planting. They are also called multipurpose tree species. Their foliages, flowers, fruits and seeds are often very good source for fertilizers, multi, stock feed and even tasty nutrient rich food for human. Village people are benefited not only biomass fuel but also many other aspects from growing these trees. (8) Community Forestry Community forestry (CF) is recognized as an important strategy to manage the forest at sustainable manner in Cambodia. The majority case of CF activity is managing existing primary or degraded forest rather than reforestation by planting. They are organized by the government (MOE for conservation area and DFW for production area) or NGOs. The methodology varies a lot depending on the forest status and social environment. Some are only zoning forest for human activities such as fuel wood collection and timber harvesting. Some carries out forest management practice such as thinning, weeding and enrichment planting. A technical advisor of Concern Worldwide (NGO) told us that they carried out thinning at one of their CF site and they harvested 60 ox cart, 12 t fresh weight (6-8 t for dry) woody biomass waste from 1 ha. Village people refuse to conduct further thinning practice after some hectare of operation because they cannot utilise so much of wood. Such excess wood residues of forest management practice can be used for electricity generation. |
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| 3.2 Current Biomass Electrification used in Cambodia | ||||
There are only three biomass fuelled electricity generation facilities in Cambodia. Two of them are introduced mainly for research purposes and only one system is operating for practical use. The details are described below. (1) Centre for Livestock and Agriculture Development (CelAgrid) CelAgrid is the institute conducting various research on rural development mainly based on agricultural technologies. There are 17 academic staff and 40 students working in the institute. They purchased a 9 kWe (gross) biomass gasification electricity generation system from Ankur Scientific (India) in September 2004 (Figure 3.2.1). Mr. M. Phalla is currently conducting a research on comparing different biomass such as coconut husk, cassava stem, mulberry stem and Cassia tree for suitability and efficiency for gasification. |
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Source: JICA Study Team Notes: The orange body at the back is the gasifier and the front green part is the generator unit. Figure 3.2.1 The 9 kWe Woody Biomass Gasifier Installed to Centre for Livestock and Agriculture Development |
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| (2) Anlong Ta Mei Community Energy Project Anlong Ta Mei village (Bannan District, Battambang Province) community energy cooperative project is the only biomass electricity supply system operated profitable base rather than research. The project introduced a 9 kWe biomass gasification electricity generation system (same model as CelAgrid) and set up a mini grid. They use planted Leucaena branches for the fuel. They started the operation in February 2005 and currently supplying electricity to 70 households for 7 hours (4:30-11:30 pm) a day. (3) NEDO SV and Biogas Hybrid Power Generation Project In December 2003, Japan’s NEDO completed the construction of a hybrid electricity generation system consist of a solar photovoltaic (50 kW) and 2 x 35kWe duel fuel biogas engine near Sihanoukville. The biogas is extracted from cattle excrements from a farm. The system is currently operating but the project is considered to be mainly a demonstration and research venture and would not economically viable yet. |
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