Copper-based Solar Cells: Good for the Environment, Good for the Consumer Copper has long been used in solar heating/hot water systems, where it is commonly used in heat exchangers. Now, it promises to become equally valuable in photovoltaic (PV) systems. These systems produce electricity through the action of sunshine on certain semiconductors, including so-called thin-film materials and the currently most promising material: copper indium gallium diselenide or CIGS.
The Presidential Dollars Golden Collectibles or the Next Coin of the Realm? The U.S. Mint is betting it's got it right this time. The Mint placed into circulation the first of its new golden dollar coins featuring, for the initial issue, George Washington.