The way to the energy sustainable world

Abstract The relatively short lifetime of fossil fuel resources, except coal, and the serious environmental impact of using them, demand new solutions to the world-growing primary energy demand. A proposed vertically/horizontally energy-integrated system (VHIES) with three main energy carriers: methane, methanol and electricity, and with sulphuric acid (as a product from flue gas desulphurization) for seasonal heat storage can be a solution for the future. The system is entirely compatible with the present one and will enable efficient accumulation of solar energy. At a certain time in the future, an energy and ecology equilibrium state will be reached on the planet Earth.