Ancient history is the aggregate of past events WordNet Search - 3.0, "History" from the beginning of recorded human history to the Early Middle Ages or the Postclassical Era. The span of recorded history is roughly 5,000 years, with Cuneiform script, the oldest discovered form of coherent writing, from the protoliterate period around the 30th century BC.see Jemdet Nasr period, Kish tablet; see also The Origin and Development of the Cuneiform System of Writing, Samuel Noah Kramer, Thirty Nine Firsts In R..
Cogeneration or combined heat and power ( CHP) is the use of a heat engine Cogeneration and Cogeneration Schematic, www.clarke-energy.com, retrieved 26.11.11 or power station to simultaneously generate electricity and useful heat. Trigeneration or combined cooling, heat and power ( CCHP) refers to the simultaneous generation of electricity and useful heating and cooling from the combustion of a fuel or a solar heat collector. A plant producing electricity, heat and cold is called a trigeneration or poly..
