Can we emulate nature to store energy as heat?  Think about the core of our planet.  It is a giant ball of molten rock, right?  This heat can be harnessed for energy production when it’s close enough to the surface.  So essentially the core is a giant battery right?  Can we make our own “giant batteries”?  Can we build solar collectors to concentrate the sun’s rays to super heat some sort of element that has efficient thermal properties?