With the conversion of most oil refineries to processing and the increase in the demands by company managers to reduce the costs for oil refining, conservation of energy resources has become especially critical. For refineries with a low proportion of secondary processes, the costs of energy resources are 25-30% of the total costs for production of petroleum products, and when the proportion of secondary processes increases, these costs increase significantly and can attain 40% with a greater than 80% degree of oil refining.