Life cycle assessment comparison of technical solutions for CO 2 emissions reduction in power generation

Abstract

An exergetic life cycle assessment (ELCA) and a classical environmental life cycle assessment (LCA) have been performed for three carbon dioxide low emission power cycles. The configuration of the power cycles are: a semi-closed gas turbine combined cycle with CO 2 reduction from the exhausts by means of amine solution chemical absorption; an integrated gasification combined cycle with CO 2 reduction from the synthesis gas by means of amine solution chemical absorption; and O 2/CO 2 innovative cycle where, burning methane in oxygen, CO 2 becomes the cycle working fluid, and the CO 2 excess, produced in the combustion, is removed in liquid phase without any additional system. The LCA is mainly focussed on CO 2 production during the three phases of construction, operation and dismantling of the plants. This is necessary to verify if the process is effective in terms of CO 2 reduction. Besides the classic LCA, also an ELCA was performed, whose aim is to assess the cost, in terms of exergy losses, of the life cycle of the plants. The CO 2 reduction is effective during the lifetime, and a sort of classification of the studied plant is obtained.