A role for Renewables Toward Sustainable Energy Systems

Abstract

The use of fossil fuels causes not only the exhaustion of non-renewable resources, but also environmental problems such as global warming.The world needs to establish sustainable energy systems that are fossil fuel-free and fully renewable before the exhaustion of fossil fuels are or catastrophic climate change. To find the shape of the sustainable energy systems, the author has developed a global land use and energy model (GLUE). The model accommodates future global energy supply systems, considering cost minimization. The model includes overall energy resources, including fossil fuels and renewables, and overall energy conversion technologies, including a variety of technologies concerning power generation, gasification, and liquefaction. The global land use and energy model includes new technological concepts such as intermittent renewables (photovoltaic and wind) with small capacity storage and with large capacity storage. In the sustainable scenario in 2060, the dominant resource of primary energy supply will be photovoltaic directly connected with electrolysis, at the global level of 445 EJ/year. The second and the third largest resources are biomass and photovoltaic with large capacity storage at 332 EJ/year and 116 EJ/year respectively. At that time, the dominant energy resource for power generation connected with the electricity grid will be photovoltaic with largecapacity storage at 116 EJ/year in the world. Globally, BGCC (biomass gasifier combined cycle), hydropower, and photovoltaic with small capacity storage are greater than 40 EJ/year each. However, the energy system costs in the sustainable energy scenario will be at 19 trillion US$/year, almost three times as expensive as the costs in the base case.