The rapid growth of large-scale energy storage is driven by plunging battery prices , rising electricity demand and a recognition among operators, utilities and public officials that grids are less ...

De Forest put a metal grid in the middle of the vacuum tube. By using a small input current to change the voltage on the grid, De Forest could control the flow of a second, more powerful current ...

US company Brick It sells the metal grids and thin bricks which fit onto the grids. They're available in different colours and styles. Watch the video to see how they are fitted. Produced by David ...