Potential for rural electrification based on biomass gasification in Cambodia
Abstract
Around 76% of the 10,452 villages of Cambodia will still be without electricity in the year 2010. We examined the potential of biomass gasification fuelled by alternative resources of agricultural residues and woody biomass to increase rural power supply, using geographic and social economic databases provided by the Royal Government of Cambodia. About 77% of villages currently without electricity have sufficient land available for tree planting for electricity generation based on a requirement of 0.02 ha per household. Among 8008 villages with sufficient land, we assumed that those villages that had greater than 10% of households owning a television (powered by a battery or a generator) would have both a high electricity demand and a capacity to pay for electricity generation. Those 6418 villages were considered appropriate candidates for mini-grid installation by biomass gasification. This study demonstrated that while agricultural residues such as rice husks or cashew nut shells may have high energy potential, only tree farming or plantations would provide sufficient sustainable resources to supply a biomass gasification system. Cost per unit electricity generation by biomass gasification is less than diesel generation when the plant capacity factor exceeds 13%. In order to ensure long-term ecological sustainability as well as appropriate tree-farming technology for farmers, there is an urgent need for studies aimed at quantifying biomass production across multiple rotations and with different species across Cambodia.
6. Conclusion
Tree farming for biomass production by local farmers is likely to be the most sustainable method of fuel supply for biomass gasification electricity generation for a rural mini-grid. More than 60% of the villages in Cambodia expected to be still without electricity in 2010 are potential candidates for biomass gasification mini-grid in terms of land availability for tree planting and ability to pay for electricity by villagers. Biomass gasification is economically competitive compared with diesel generation. The cost for unit electricity generation of biomass gasification becomes lower than diesel generation when the plant capacity factor exceeds by 13%. The largest cost associated with power generation via biomass gasifier is the depreciation, which could be reduced if gasifiers were manufactured locally. However, there are few accurate estimates of the productivity of plantations and tree farms in Cambodia. In order to ensure long-term ecological sustainability as well as appropriate tree farming technology for farmers, there is an urgent need for further studies that quantify biomass production across multiple rotations and with different species across Cambodia.
Acknowledgements
This study was conducted as part of a project funded by the Japan International Cooperation Agency (JICA): ‘The master plan study on rural electrification by renewable energy in the Kingdom of Cambodia’. The authors thank SME Cambodia for providing data about the Anlong Ta Mei biomass electrification project. Khieu Borin and Miech Phalla of the Center for Livestock and Agriculture Development provided biomass fuel efficiency test for gasification. Nakorn Worasuwannarak of The Joint Graduate School of Energy and Environment and King Mongkut's University of Technology Thonburi, Thailand provided the ultimate analyses of biomass samples. Ung Chanpisey and Takeshi Okamura of the JICA study team provided logistical support. We also thank three anonymous reviewers for their valuable comments and criticism.