Assessment of the biomass energy potentials and environmental benefits of Jatropha curcas L. in Southwest China
Introduction
As an important renewable new energy, biofuel (including biofuel ethanol and biodiesel) has attracted extensive attention of governments and enterprises throughout the world [1]. To safeguard national energy security, to reduce greenhouse gas emission and to promote the living standard of peasants are the major causes driving the rapid development of biofuel industry [2]. At present, developed countries in Europe and America and some developing countries have formulated the plans to develop biofuel, and large-scale development is underway. China is one of the major producing countries of biofuel, ranking the fifth in the world in 2009 in terms of total production [3]. However, due to the scarcity of China's farm land resources, Chinese government issued a policy in 2007, to restrict the expansion of biofuel using grain as raw material in order to safeguard food security. Meanwhile, the development focus is shifted to the biofuel made from other raw material other than grain. Forestry biodiesel has the advantages of “not using the grain intended for human consumption and not occupying the land intended for grain production”, thus attracting the attention of many developing countries including China [1]. Jatropha curcas L. (JCL) is considered to be the most promising tree species used to produce biodiesel [1], [4]. Southwest China has the richest land resources suitable for energy plants development and with concentrated distribution. Moreover, because of its better meteorological conditions of temperature, precipitation and humidity, Southwest China is the major area for the development of JCL [5]. The local government has established development plan for JCL. For example, Yunnan, Sichuan and Guizhou have come up with such plan since 2006, attempting to plant 1667 thousand hectares of JCL using marginal land resources in the next 15 years.
China's biodiesel industry using JCL as raw material is witnessing rapid development. However, the development of biodiesel industry is still faced with many uncertainties, among which the accurate estimation of the potentiality of raw material supply, net energy production and greenhouse gas (GHG) emission reduction is the most crucial issue. Currently, the appraisals of biodiesel supply potential of JCL, i.e. the researches on the quantity and quality of land resources suitable for JCL plantation, have been many [1], [5]. The analysis of regional energy potential of JCL is mostly limited to this aspect, while the appraisal outcome of net energy production potential of JCL is rare. The appraisal of GHG emission reduction potential is little more than rough estimation in most cases, without the quantitative estimation based on scientific statistics and approaches. Therefore, operable techniques and approaches should be developed so that the accurate appraisal of supply potential of raw materials, net energy production potential and GHG emission reduction potential in the exploitation and utilization of biofuel from JCL can be achieved. It is hoped that this appraisal will provide statistical support for the formulation of environmental protection policy, GHG emission reduction policy and related industry policy by national and local government.
In the appraisal of net energy production potential and GHG emission reduction potential, life cycle analysis (LCA) has been proven to be a feasible method [6], [7], [8], [9], [10]. LCA is a method to appraise and analyze the environmental impact and energy consumption of a product or system in the entire life cycle from the acquisition of raw material, production, usage to post-usage treatment [6]. LCA has been widely applied in the appraisal research on bioenergy impact [7], [8], [9], [10]. At present, the researches on life cycle net energy and GHG emission reduction of energy plants cultivated on marginal land resources of different suitability degrees remain to be conducted. Moreover, the researches on the estimation of regional total net energy production potential and GHG emission reduction potential by integrating marginal land resources suitable for energy plants cultivation with LCA are also rare.
Five provinces in Southwest China, including Yunnan, Guangxi, Guizhou, Sichuan and Chongqing, are taken as the study areas in this paper. First, the potentiality, degree and spatial distribution of marginal land resources suitable for planting JCL are determined. Next, LCA-based analytical model of net energy production potential and GHG emission reduction potential of biodiesel produced from JCL is established. By this means, the analysis and appraisal of maximum net energy amount and GHG emission reduction potential of biodiesel from JCL in Southwest China can be achieved, thus offering technical methods and typical cases for analysis of development potentials and environmental benefits of biofuels derived from energy plants.
Section snippets
Method
The research is conducted in the following procedures:
- (1)
Identification and appraisal of marginal land suitable for JCL planting: multi-factor comprehensive analysis is adopted to identify marginal land resources suitable for JCL planting and conduct suitability appraisal. By this means, their spatial distribution, suitability degree and total amount are obtained.
- (2)
LCA net energy and GHG emission reduction capacity of biofuel from JCL: LCA is used to study the life cycle net energy amount and GHG
Results of suitability appraisal of land resources for JCL planting
Multi-factor comprehensive analysis is conducted (Section 2.1) to calculate the amount of land resources suitable for large-scale development of JCL. The results are shown in Figs. 2, 3, and Table 4, from which the following conclusions are reached:
- (1)
Generally speaking, the area of land suitable and moderately suitable for JCL planting is 1.99 × 106 ha and 5.57 × 106 ha, respectively, among which the suitable land resources are predominated by sparse forest land and grassland.
- (2)
Suitable land
Conclusion
Through the combination of multi-factor comprehensive analysis and LCA, the marginal land resources, total net energy production and GHG emission reduction potential of the JCL biodiesel are estimated in Southwest China. Following conclusions have been achieved:
- (1)
The area of land suitable and moderately suitable for JCL planting is 1.99 × 106 ha and 5.57 × 106 ha, respectively, among which the suitable land resources are predominated by sparse forest land and grassland. Suitable land resources
Acknowledgments
This research was supported and funded by the Chinese Academy of Sciences (Grant No. KZZD-EW-08) and State Key Laboratory of Resources and Environmental Information Systems of China.
References (23)
- et al.
Assessment of bioenergy potential on marginal land in China
Renew Sustain Energy Rev
(2011) - et al.
Life cycle assessment, part 1: framework, goal and scope definition, inventory analysis, and applications
Environ Int
(2004) - et al.
Energy efficiency and potentials of cassava fuel ethanol in Guangxi region of China
Energy Convers Manag
(2006) - et al.
Life cycle inventory and energy analysis of cassava-based fuel ethanol in China
J Clean Prod
(2008) - et al.
A GIS-based approach to evaluate biomass potential from energy crops at regional scale
Environ Model Softw
(2010) - et al.
Environmental assessment: (LCA) and spatial modelling (GIS) of energy crop implementation on local scale
Biomass Bioenergy
(2011) - et al.
Potential land for plantation of Jatropha curcas as feedstocks for biodiesel in China
Sci China Ser D-Earth Sci
(2009) - et al.
Review of environmental, economic and policy aspects of biofuels policy research
(Sept.2007) Renewables 2010 global status report
(2010)A survey of the woody plant resources for biomass fuel oil in China
Sci Tech Rev
(2005)
Energy consumption and GHG emissions of six biofuel pathways by LCA in (the) People's Republic of China
Appl Energy
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