The effect of solar energy on the environmental profile of electricity generation in Chile: a midterm scenario

Abstract

The Atacama Desert in Northern Chile features the highest solar radiation on continental soil worldwide, ranging within 2,500–3,400 kWh/m2/year, with UV-B radiation levels 65% above average European. This desert covers an extension over 105,000 km2 receiving more than 4,000 hours of sunshine yearly, and hosts large reserves of copper, lithium, molybdenum and other metallic and non-metallic minerals. Thus, the Chilean mining industry accounts for more than 30% of the total electricity consumption in the country. During the last 3 years major investments on solar photovoltaic (PV) plants have taken place at the Atacama Desert, driven by the drastic drop in the cost of PV technology, and incentives provided by the new Energy 2050 Roadmap set by the Chilean government, with view to fostering the introduction of renewable energy sources in the electricity market. The Chilean electricity system is composed of two connected grids, namely the Greater Northern Network (SING) and the Central Network (SIC), with a total installed capacity of nearly 21 GW. The SING network is mostly composed of thermoelectric power plants, whereas the SIC network features a significant share of hydroelectric plants, leading to different carbon footprint, namely 0.9 and 0.3 ton CO2eq/MWh, at SING and SIC, respectively. At the end of 2017, those grids were connected to meet the current 80 TWh/year national demand. Massive introduction of PV electricity generation plants at the Atacama Desert is foreseen in the near future, to reach a projected share around 25% by 2050. Within this framework, this paper presents novel results on the effect of solar energy on the environmental profile of electricity in Chile in a midterm scenario, using a life cycle assessment approach, under conditions of drastic reductions in water availability due to climate change. Results show that PV systems make a significant contribution to environmental impacts associated to electricity generation in the national mix by 2050, mainly in ozone layer depletion, abiotic depletion, global warming, acidification, and photochemical oxidation potentials impact categories, mainly from upstream transport and cell manufacturing. The extent of those impacts could increase significantly if the PV lifespan decreases due to cells degradation as a result of harsh environmental conditions, highlighting the need for reliable data on this key parameter.