Making green technology greener: Achieving a balance between carbon and resource savings through ecodesign in hydropower systems

摘要

Renewable energy systems reduce the greenhouse gas (GHG) emissions associated with energy generation. However, we live in a world with depleting reserves of natural resources, and significant quantities of raw materials are often embodied within renewable energy infrastructure. This paper examines the potential for ecodesign measures to improve the GHG and resource balance of five small-scale hydropower case studies (50-650 kW). A life cycle assessment (LCA) approach compares two specific environmental impact categories: global warming potential (GWP) and abiotic resource depletion potential (ARDP). A number of ecodesign measures were examined for each installation: powerhouse structure, concrete selection, roofing materials, excavation work and transportation. Ecodesign led to cumulative savings of between 2.1% and 10.4% for GWP, and ARDP savings of between 0.1% and 2.6%, for the hydropower installations. Small savings were made with each ecodesign measure applied in all case studies. Furthermore, applying a 1% materiality threshold as outlined by LCA standards was shown to under-estimate the total project burdens, and to neglect opportunities for burden savings through ecodesign. Ecodesign can promote the use of locally sourced materials and some measures can lead to time savings during the construction process. The findings demonstrate the potential for ecodesign to modestly improve the carbon and resource efficiency of hydropower projects. (C) 2015 Elsevier B.V. All rights reserved.