The large magnitude of solar energy available makes it a highly appealing source of electricity. The United Nations Development Programme in its 2000 World Energy Assessment found that the annual potential of solar energy was 1,575â49,837 exajoules (EJ).
Definition of IRONWOOD. 1. : any of numerous trees and shrubs (as a hornbeam or hop hornbeam) with exceptionally tough or hard wood. 2.: the wood of an ironwood.See ironwood defined for kids.ADVERTISEMENT.. : any of numerous trees and shrubs (as a hornbeam or hop hornbeam) with exceptionally tough or hard wood. 2. : the wood of an ironwood. See ironwood defined for kids.
Gray iron. Micrograph of grey cast iron. Gray iron, or grey cast iron, is a type of cast iron that has a graphitic microstructure. It is named after the gray color of the fracture it forms, which is due to the presence of graphite. It is the most common cast iron and the most widely used cast material based on weight.