The carbide production and the subsequent production of cyanamide was started in 1908 after the water power plant was operational and provided the necessary electricity for the arc furnaces. The plant was the largest in the world and remained operational till 2003 shortly after the plant was sold to Philipp Brothers Chemicals Inc. The Norwegian government tried to get the site recognized together with other industrial plants as a UNESCO World Heritage Site. In 2010 an international report stated: "What makes Odda smelteverk so important and central to the application of Norway’s hydro power sites and pioneer chemical industry as a World Heritage Site is the fact that here in an internationally unique way the physical remains of an early chemical production process are still present."