Reduction of life cycle impacts of oil shale electricity caused by the shift to fluidized bed combustion technology

Abstract

In 2004–2005, the pulverized firing technology that had been used for decades was replaced with fluidized bed combustion in some boilers of two major power plants located in North-East Estonia. The objective of the current study was to identify the impact of this technology switch on the efficiency, resource use and environmental performance of oil shale electricity generation. The Life Cycle Assessment (LCA) methodology according to the International Organization for Standardization (ISO) 14040 series and the International Environmental Product Declaration (EPD) System standards was applied to analyzing the effects of the mentioned technology switch. In this study, the functional unit of the product system of oil shale electricity is 1 kWh of oil shale electricity transmitted to the Estonian customer. The specific oil shale electricity inventory data that can be used in life cycle assessments of other products are presented. The comparison of the life cycle environmental impact of oil shale electricity before and after changing the combustion technology is provided. Climate change caused by greenhouse gas emissions is the key impact to be tackled. The gain in electricity generation efficiency due to the change of the combustion technology had a remarkable positive impact on greenhouse and acidifying gas reduction. Also, the impact on creating ground-level ozone and eutrophication diminished. Reduction of ozone depleting gases, however, was minimal. The critical review of this LCA has been carried out by an independent expert.

Keywords

• estonian oil shale
• oil shale thermal power plant
• oil shale electricity inventory data
• life cycle assessment.