Summary. Energy consumption of domestic oil transportation systems to ensure their energy efficient operation in terms of diversification of sources of hydrocarbons was studied.

Keywords: alternative sources of oil, Iranian oil, oil transportation systems, energy efficiency, energy consumption.

Summary:The article explores the effect of the heat of friction of the flow on the change of the temperature conditions of pumping high-viscosity oils through crude oil pipelines.

Keywords: heat of friction of the flow, full heat transfer coefficient , main pipeline,  high-viscosity oil, loss of the head due to friction.