| Work Detail |
New research has shown that floating alpine photovoltaic systems can outperform lowland or ground-based systems in terms of energy efficiency and sustainability. Researchers at the Zurich University of Applied Sciences have analysed the environmental life-cycle impact of the worlds first high-altitude floating photovoltaic system and found that it has an energy payback period of just 2.8 years. The 448 kW system was built in 2019 by Swiss energy provider Romande Energie on the surface of Lac des Toules, a reservoir located at an altitude of 1,810 metres in the Swiss Alps. “The installation consists of 35 platforms equipped with bifacial photovoltaic panels. It covers 2% of the lake’s surface and has a total size of 2,240 m2,” the scientists noted. “The structure is anchored to the bottom of the reservoir. Between mid-June and mid-December, the installation is afloat, and the rest of the year it rests on a platform on the bottom of the reservoir.” They also explained that their Life Cycle Assessment (LCA) evaluation took into account all processes, from the extraction of raw materials used to build the system to the end of its useful life. They then compared the environmental performance of the facility to that of conventional and lowland systems, under four scenarios. “Primary data was provided by the energy company in question and includes data from all life cycle phases of the high-altitude PV installation,” they further explained. “Secondary data was collected through the literature, and focuses on the International Energy Agency (IEA) methodological guidelines and the Product Environmental Footprint Category Rules (PEFCR).” The analysis showed that the high-altitude floating array emits about 94 g of CO2-eq per kWh of electricity produced over its entire life cycle. The system was also found to have a lower impact on the environment compared to other types of systems, due to its higher energy efficiency and reduced land use. However, their “environmentally intensive” mounting systems were identified as a critical element that increases the environmental impact of the installation. These mounting systems require more elaborate foundations and are preferably double-piled, which implies a greater use of aluminum, which can be up to eight times higher than that of ground-mounted PV installations. Furthermore, the scientists stressed that reducing aluminium in the mounting system would not only have environmental benefits, but would also contribute to reducing the costs of the floating PV installation. “This can be done by reducing overall aluminium quantities, focusing on the use of recycled aluminium or replacing aluminium with an alternative material,” they added. The analysis also showed that the Alpine installation had a lower impact in six of the twelve categories analysed and a higher impact in the other six. “The demand for non-renewable primary energy amounts to 10,810 kWh oil-eq/kWp, which is equivalent to an energy payback period of 2.8 years,” the researchers stated. Sus conclusiones figuran en el artículo “Are alpine floatovoltaics the way Forward? Life-Cycle environmental impacts and energy payback time of the Worlds’ first High-Altitude floating solar power plant“, publicado en Sustainable Energy Technologies and Assessments. “This study adds to the limited knowledge on the environmental performance of floating photovoltaic systems and provides insight into the environmental impact of such high-altitude installations,” the scientists conclude. “The study thus identifies leading points for improving environmental performance, while highlighting the potential of this technology.” |
