Life Cycle Assessment of a Small Hydropower Plant in Iceland: A Case Study of a 9,9 MW Hydropower Plant

Abstract

In Iceland, the potential environmental impact of hydropower plants is categorized by their installed electrical capacity. Small hydropower plants have installed capacity of less than 10MW and are considered to have insignificant impacts on the environment. These hydropower plants are not included in the Master Plan for Nature Protection and Energy Utilization, nor are they required to undergo an environmental impact assessment (EIA), unless otherwise requested by the National Planning Agency. In recent years the number of small hydropower plants, scaled just below the 10MW limit, has been increasing. This is a potential concern as there is negligible supervision of these projects, which could risk losing overview of hydropower options feasible for utilization, and potentially result in significant and irreversible impact on the environment. In this study, the environmental impacts of a 9,9 MW hydropower plant in Iceland are quantified, using the method of life cycle assessment (LCA), but currently LCA is not integrated into the processes of EIA in Iceland. The functional unit is ‚1 kWh of electricity produced at any given time over a 60-year lifetime, in a 9,9 MW run-of-river hydropower plant in Iceland´. The results show a global warming potential (GWP) of 4 g CO2 equivalent per kWh. A sensitivity analysis was performed, exploring the impacts of extended lifetime, concrete dam, and reduction in capacity factor. Extended lifetime reduced the GWP to 3 g CO2 equivalent per kWh, while a concrete dam, and reduction in capacity factor sugessted increased burdens of all impact categories. The results were compared to previously conducted life cycle assessments of larger Icelandic hydropower plants, indicating a potentially higher impacts from small hydropower plants.