effective heating area
41Europe, history of — Introduction history of European peoples and cultures from prehistoric times to the present. Europe is a more ambiguous term than most geographic expressions. Its etymology is doubtful, as is the physical extent of the area it designates.… …
42Solar hot water — is water heated by the use of solar energy. Solar heating systems are generally composed of solar thermal collectors, a fluid system to move the heat from the collector to its point of usage. The system may use electricity for pumping the fluid,… …
43art conservation and restoration — Maintenance and preservation of works of art, their protection from future damage, deterioration, or neglect, and the repair or renovation of works that have deteriorated or been damaged. Research in art history has relied heavily on 20th and… …
44Wood fuel — is wood used as fuel. The burning of wood is currently the largest use of energy derived from a solid fuel biomass. Wood fuel can be used for cooking and heating, and occasionally for fueling steam engines and steam turbines that generate… …
45radiation — radiational, adj. /ray dee ay sheuhn/, n. 1. Physics. a. the process in which energy is emitted as particles or waves. b. the complete process in which energy is emitted by one body, transmitted through an intervening medium or space, and… …
46steel — steellike, adj. /steel/, n. 1. any of various modified forms of iron, artificially produced, having a carbon content less than that of pig iron and more than that of wrought iron, and having qualities of hardness, elasticity, and strength varying …
47Carbon tax — Part of a series on Green economics Concepts …
48Sun — This article is about the star. For other uses, see Sun (disambiguation). The Sun …
49Soldering — For the song, see Soldering (song). For the product, see Solder. Desoldering a contact from a wire. Soldering is a process in which two or more metal items are joined together by melting and flowing a filler metal (solder) into the joint, the… …
50architecture — /ahr ki tek cheuhr/, n. 1. the profession of designing buildings, open areas, communities, and other artificial constructions and environments, usually with some regard to aesthetic effect. Architecture often includes design or selection of… …
