ارزیابی مبتنی بر GIS از منابع انرژی تجدید پذیر محلی گوناگون : یک مطالعه موردی منطقه Chigu از جنوب غربی تایوان

The issue of regulating greenhouse gas emissions of developing countries is one of the main reasons for the US's retreat from ratifying the Kyoto Protocal, and this deserves particular attention in order to ensure that a robust international climate policy exists in the future. Enabling developing countries to move toward low-carbon energy systems would enhance the feasibility for their participation in mitigating greenhouse gas emissions. This study evaluates wind, solar, and biomass energy sources in a rural area of Chigu in southwestern Taiwan by means of analyzing technical, economic, environmental, and political implications in order to establish an evaluation model for developing local renewable energy sources. The adopted approach evaluates local potentials of renewable energy sources with the aid of a geographic information system according to actual local conditions, and allows the assessment to consider local potentials and restrictions such as climate conditions, land uses, and ecological environments, thus enabling a more-accurate assessment than is possible with evaluations on an approximate basis. These results may help build a developmental vision for sustainable energy systems based on locally available natural resources, and facilitate a transition of national energy and environmental policies towards sustainability.

The issue of global warming is becoming a great challenge which the international community must face in this century. The latest report of the IPCC (Intergovernmental Panel on Climate Change) in 2001 indicated that development heavily relying on fossil fuel energies will raise global mean temperatures by about 4.5 °C during the 21st century. Only with a transition toward a low-resource-consuming economy and the use of clean energy sources and technologies will it be possible to mitigate temperature increases to about 2 °C (IPCC, 2001). In other words, cutting energy consumption and facilitating a transition of energy structures towards renewable energy sources have become necessary alternatives for humanity in order to stabilize the global climate system. This holds for both developed and developing countries. Substituting fossil fuels with renewable energy sources is regarded as a significant measure for cutting global carbon emissions (Brown, 2003; Houghton, 1997; IPCC, 2001). Full use of these sources can help mitigate global warming in environmental terms, meet energy needs in economic terms, and provide employment for rural areas in socioeconomic terms (Thothathri, 1999; UNCSD, 2002; Yue et al., 2001). All these indicate their sustainability for global and local development. In addition to a legislative framework set at the national level for their promotion, locally based evaluations for developing renewable energy sources can provide a vital basis for evaluations at the national level, and thus enhance political effectiveness. In this context, this study attempted to investigate the Chigu area of southwestern Taiwan as an example, and to establish a procedure for evaluating local renewable energy sources. With geographic information system (GIS)-based analyses, multifarious renewable energy sources were evaluated according to actual local land uses in order to provide more-integrated and accurate decision-making information for policy-makers and investors. The established model may help localities explore their exploitable resources, and this can possibly be expanded to conduct comprehensive surveys at the national level in order to estimate the entire potential of a country. These represent indispensable information for decision-making in order to build a sustainable energy system which enhances climate protection.

This survey of renewable energy sources in the Chigu area has reached the following conclusions. • The installation capacity of wind energy amounts to 2356 MW with a generation capacity of 3255 GWh annually in scenario R. For scenario W, installation capacity is calculated to be 2008 MW with a generation capacity of 2672 GWh. These demonstrate a far greater potential for the development than photovoltaics and biomass. This can to a great extent be attributed to the advantageous geographical conditions of a windy coastal area and of a low-density population distribution. • The installation capacity of photovoltaics of 52 MW with an annual energy output of 80 GWh is restricted to the application on rooftops rather than for extensive land areas under the consideration of reserving the limited land resources in Taiwan. Its potential is none the less greater than that of biomass. The introduction of this technology should, however, be promoted since its application can be expanded to building facades and other facilities on the one hand, and its electricity generation (supply side) is close to consumers (demand side) which enhances the value of the generated electricity on the other. • Biomass energy could be used to generate ethanol with energy values of 38 and 31 GWh for scenarios R and W, respectively, which could serve as fuels for motorized vehicles. In addition, about 22 and 18 GWh of electricity could be generated from fully using the bagasse in scenarios R and W, respectively. Despite the relatively lower potential, the production of this energy source is not subject to climate-induced fluctuations that would be imposed on energy from wind and photovoltaics. This makes biomass energy an ideal complement for energy produced from wind and photovoltaics. The approaches adopted in this study have the following implications for exploiting local renewable energy sources: • The GIS-based approach of evaluating local potential of renewable energy sources adopted in this study takes into account actual local conditions and restrictions such as climate conditions, land uses, and ecological environments which produces a more-accurate assessment than evaluations on an approximate basis. • The process of evaluating local renewable energy sources adopted in this study using technical, economic, environmental, and political analyses can serve as an example to investigate local and domestic renewable energy sources with vertical integration. The results of such surveys can help formulate local and national long-term energy and environmental policies. • The simultaneous evaluation of multifarious sources in this study could help combine various renewable energy sources with horizontal integration in order to provide complementary and more-sufficient power supplies, and consequently enhance their capability for supplying electricity. • The scenario analyses adopted in this study could be used to assess energy-economic and environmental implications of exploiting renewable energy sources under different considerations in the study area, whether prioritizing renewable energy or wildlife. This information is valuable for both governmental decision-making and political debate at the local level. • Based on the methodologies adopted in this study, other renewable energy sources and criteria of exploitation could be evaluated according to actual conditions at the local level. With the aid of GIS, an evaluation of multifarious renewable energy sources according to local real land uses is able to provide more-integrated and accurate decision-making information for policy-makers and investors. This approach can further be expanded to conduct a comprehensive survey at the national level in order to grasp the entire potential of a country. These implications may help build a developmental vision for sustainable energy systems based on locally available natural resources, and facilitate a transition of national energy and environmental development towards sustainability.