Environmental Impact Evaluation for Renewable energy: A Case Study for Biomass Pyrolysis Oil

[[abstract]]Owing to the limits of nature resources, the energy supply in Taiwan is highly dependent on imports. In 2009, 99.37 percent energy is imported from abroad. In the times that global fossil energy is getting exhausted, the uncertainty of energy supply will be considerably severe if the ratio of indigenous energy couldn’t increase in the near future. Besides, the consumption of traditional fossil fuels also produces considerable CO2 emission. For achieving the goals of sustainable development and CO2 reduction, the improvement of energy efficiency and development of locally low-carbon alternative energy has become the key issue for Taiwan. In terms of the achievability of dual objectives: disposal the waste and increase the energy production, bio-energy has received more attention in recent years.Wood pyrolysis is one of the earliest energy conversion forms. It was used to produce charcoal as fuel for iron and steel industry. Modern pyrolysis technology can be widely applied in many kinds of biomass, includes the extraction of volatiles, liquids as well as solid carbon. Depends on the energy carries (gas, liquid or solid), the pyrolysis technologies could range from slow heating to flash pyrolytic methods1. Fast pyrolysis is a process that organic materials are rapidly heated to 450~600oC in the absence of air. By fast pyrolysis technology, vapors, permanent gases and charcoal will be produced, and the vapors will be condensed into pyrolysis oil. In general, the conversion ratio is about 60 wt.%. Owing to the multiple advantages, including high rate of oil production, high tolerance for different raw materials, high cost-effective, whole crop usage as well as low system capacity demand, pyrolysis oil has great potential to become a viable alternative to fossil fuel. However, the fast pyrolysis technology is under development in Taiwan. There’s still a need to evaluate the energy efficiency and environmental impact for using biomass pyrolysis oil as an alternative energy. Hence, Life Cycle Assessment (LCA) technology was employed in the study to state the input and output flow among multiple stages, and further realizing the advantage, barrier and possible environmental impact brought from the development of biomass pyrolysis oil in Taiwan