Toward carbon neutrality: Projecting a desert-based photovoltaic power network circumnavigating the globe.

Carbon, the human's most reliable fuel type in the past, must be neutralized in this century toward the Paris Agreement temperature goals. Solar power is widely believed a key fossil fuel substitute but suffers from the needs of large space occupation and huge energy storage for peak shaving. Here, we propose a solar network circumnavigating the globe to connecting large-scale desert photovoltaics among continents. By evaluating the generation potential of desert photovoltaic plants on each continent (taking dust accumulation into account) and the hourly maximum transmission potential that each inhabited continent can receive (taking transmission loss into account), we find that the current total annual human demand for electricity will be more than met by this solar network. The local imbalanced diurnal generation of photovoltaic energy can be made up by transcontinental power transmission from other power stations in the network to meet the hourly electricity demand. We also find that laying solar panels over a large space may darken the Earth's surface, but this albedo warming effect is orders of magnitude lower than that of CO released from thermal power plants. From practical needs and ecological effects, this powerful and stable power network with lower climate perturbability could potentially help to phase out global carbon emissions in the 21st century.