Solar-pumped solid-state lasers for magnesium-based energy cycling

The paper proposed a fossil-fuel-free energy cycle where energy is produced by a chemical reaction of magnesium (Mg) with water. Hydrogen and heat energy from the reaction of Mg with water can be used for engines and fuel cells. Magnesium oxide (MgO) which is reaction residue of energy production is reduced to Mg by solar pumped laser. It means that solar energy is stored as chemical energy of Mg. Since there is a Mg resource of 1800 trillion tons in the ocean, Mg can be an alternative to fossil fuel used worldwide at an annual rate of 10 billion tons.