Research on Substitution Path of Clean Energy for Production System in Oil and Gas Fields: A Case Study of Tarim Oilfield

Abstract Under the goals of carbon peak and carbon neutrality, oil and gas fields enterprises undertake the tasks of oil and gas production and energy conservation and emission reduction. It is imperative to accelerate low-carbon transition and green development. However, energy consumption of production system in Tarim Oilfield Company of CNPC is mainly composed of natural gas and electricity, accounting for 92% and 8% respectively. Moreover, total energy consumption continues to increase, and the trend of carbon emission is rising under the existing production mode. Thus, clean energy such as solar energy, geothermal energy, and waste heat are utilized to produce clean electricity and heat energy. But the proportion of clean electricity and heat consumed is still less than 6% in structure of energy consumption. This is far from the transition goals of CNPC. It is urgent to speed up the development of clean energy to replace fossil energy consumed of production system. The solutions and measures were determined after many discussions. Firstly, the demand of energy were reduced by energy-saving measures. Secondly, clean electricity and thermal energy were developed to increase the proportion of non-fossil energy in the energy consumption structure. Distributed photovoltaics and waste pressure of natural gas were utilized, and green electricity was purchased to decrease consumed grid electricity and natural gas. In order to cut down consumed natural gas, a method for selecting clean heating equipment was formulated, low-cost solar thermal equipment were developed and applied, and waste heat and low-temperature air heat were explored to recycle. Then, existing processes were electrified to build low-carbon oil and gas production system coupled with the characteristics of clean energy. The results of cleaner production are very significant in the Oilfield. Overall, energy consumption was reduced by about 74,000 tce(tons of coal equivalent) and natural gas was replaced by about 4×107 m3 in 2023. As for green and low-carbon transition, while oil and gas commodities increased, total energy consumption and total carbon emission declined by about 2% and 3.5% respectively year-on-year. The electrification rate increased by 10% compared with last year. As for clean substitution, the production capacity equivalent of clean energy reached 53,000 tce, year-on-year rises of 114%. Clean heat consumption increased to 16,700 tce, a year-on-year increase of 108%. At the same time, clean electricity consumption increased to 7.4×107 kWh(kilowatt-hours), which was 615 times than that of last year. Then, six low-carbon demonstration areas and 10 carbon neutral wellsites or stations were built. As these measures are gradually implemented, it is expected that the results will be more obvious in 2024.