Sustainable Off-Grid Hybrid Energy Systems: The Case of The Astronomical Telescope AtLAST

Production and use of hydrogen as a green and renewable fuel are increasingly considered as a central component in the transition to a green economy. Green hydrogen, i.e. hydrogen produced by water electrolysis with electricity from renewable energy sources, could abate CO₂ emissions and replace fossil fuel usage within transport, heating, stationary applications and various industrial processes. In this talk we will present our latest work on off-grid low carbon renewable energy-based systems (RES) setups for the newly planned Atacama Large Aperture Submillimeter Telescope (AtLAST) and compare them to business-as-usual diesel power generated systems. We consider systems built near the telescope on the Chajnantor plateau at ∼5000 m and systems at a Valley Site, 2500 m above sea level, near the town of San Pedro de Atacama (also off-grid).<br/>Technologies included in the designed systems are photovoltaics, batteries, and hydrogen technology, sizing them according to the telescope’s projected energy demand and reliability requirements, cost assumptions for the year 2030 and site-specific characteristics (including a particular interest on the effect of high altitudes on hydrogen-based components). We assess whether 100% RES scenarios are favorable from an environmental point of view in the categories climate change, mineral resource depletion and water use. The system boundary includes the production of components, their transport to the energy system site, and the operation and maintenance of the system.<br/>We find that 100% RES scenarios have a lower CO₂e impact than high-renewable scenarios, however, the latter lower the mineral resource depletion and water use by about 27% compared to 100% RES scenarios. Applying hybrid energy storage systems increases the water use impact, while reducing the mineral resource depletion.<br/>An additional aspect of interest in our study is the proposition of a socially accepted renewable energy system where we combine an energy system model with a participatory multi-criteria analysis.<br/>Results reveal that a renewable energy system supplying the telescope could also cover 66% of the nearby community’s energy needs of San Pedro de Atacama, without additional capacity. Stakeholders inputs show this as the most attractive solution by developing an energy system where all of them benefit. Replicating similar energy systems at nearby telescopes could reduce fossil fuel-based energy generation by 30GWh annually, cutting emissions by 18-24ktCO₂eq while contributing to acceptability of new infrastructures and energy justice.<br/><br/><br/><u>Acknowledgments</u><br/>This work received fundings from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 951815 (AtLAST project). Acknowledgments to the team of WP5 (Environmental Sustainability) at UiO, Isabelle Viole, Guillermo Valenzuela-Venegas, Marianne Zeyringer. Special thanks to our astronomy colleagues for the cooperation in the interdisciplinary project AtLAST.