Shale oil extraction Energy estimates that the "ex-situ" processing would be economic at sustained average world oil prices above $54 per barrel and "in-situ" processing would be economic at prices above $35 per barrel. These estimates assume a return rate of 15%. Royal Dutch Shell announced in 2006 that its Shell ICP technology would realize a profit when crude oil prices are higher than $30 per barrel ($190/m), while some technologies at full-scale production assert profitability at oil prices even lower than $20 per barrel ($130/m). To increase the efficiency of oil shale retorting and by this the viability of the shale oil
History of oil in California through 1930 from $9.60 per barrel in 1860 to $0.25 per barrel in 1895. American oil companies including Union Oil Company became concerned with this development because oil prices had fallen too low for oil companies to maintain high profit margins. Union Oil Company and other oil companies lobbied local and federal governments to regulate the overproduction in the oil market. Their attempts, however, were futile and no regulation was passed. Oil prices remained around $1 through the end of the 19th century. At the turn of the century, oil production in California continued to rise at a booming rate. In 1900,