Aspects of Energy Saving of Oil-Producing Enterprises

: Increasing energy efﬁciency is included in the UN Sustainable Development Goals (SDGs) to be achieved by the year 2030. Enhancing energy efﬁciency is also one of the priority areas for improving the operational efﬁciency of any oil production enterprise. The energy management system of enterprises has been founded and implemented on the basis of the international standard ISO 50001:2018 and it works successfully. The energy efﬁciency strategy is formulated in the energy policy and integrated into the business model of the companies. Companies receive signiﬁcant energy savings in the exploration and production segments through technical, technological, and organizational measures. This article shows the main directions for improving the energy efﬁciency of the artiﬁcial lift well stock and the results of their implementation. The main constraints on the implementation of the energy efﬁciency policy of oil-producing enterprises have been identiﬁed and directions for improvement of energy-saving structure have been proposed. The article proposes strategic-level classiﬁcation of energy-saving measures, which is based on assessment and comparison of implementation costs, payback period, and takes into account investments into artiﬁcial lift technology, therefore allowing investment priorities in the energy management sphere to be distinguished. Advanced directions for investment in oil-production technology have been identiﬁed, and an algorithm of development and implementation of key indicators of energy consumption efﬁciency has been proposed.


Introduction
Saving electric energy resources and increasing the efficiency of their use are the key tasks of modern production.As proved by the statistics of the UN [1], the higher amount of energy consumed by one person, the better level of lifestyle that is reached, and up-to-date industrial technologies find wider use.When the energy is used inefficiently, the lifestyle level decreases directly proportional with the drop in a country's national income.
The issues of efficient use of energy during production, transformation, transportation, distribution and consumption refer to a special direction of the energy industry-energy saving [1].The tool for providing efficient energy-saving is energy management, which combines information and analytical, organizational, technical and regulatory activities.
To solve practical tasks of a complex efficient use of energy, the enterprises are following the requirements of ISO 50001 [2][3][4][5].Despite geographic, cultural and social conditions, the enterprises of any type and size are developing systems and processes for improvement of energy efficiency [6][7][8].Successful implementation depends on liabilities taken at all levels and across all functional areas [9,10].It is supposed that implementation of energy management would reduce the costs on energy by means of systematic control over energy sources.The standards set the requirements to the energy control system.Based on these requirements, an enterprise can develop and implement energy policy, set goals, tasks and develop plans of activities in accordance with legislative requirements and information connected with issues of considerable use of energy.An energy management system allows enterprises to fulfill their liabilities, formulated in the policy, take measures, which are necessary for improvement of energy efficiency, and demonstrate the correspondence of the system with requirements of the standards [11].
Energy management is based on the "continuous improvement cycle" methodology "Plan-Do-Check-Act" (PDCA) (Figure 1), which is described in the following way [11]: • Planning (plan)-carrying out energy analysis and determination of basic criteria and parameters of energy efficiency, setting goals, tasks and development of plan of activities, which are necessary for improvement of energy efficiency according to the energy policy of the enterprise; • Doing (do)-implementation of planned activities in the sphere of energy management; • Checking (check)-monitoring and measurement of processes and key characteristics of operations, that determine energy performance in relation to the implementation of energy policy and the achievement of energy goals, and reporting the results; • Action (act)-taking the measures for continuous improvement of efficiency of activities in the sphere of energy and the energy management system.
taken at all levels and across all functional areas [9,10].It is supposed that implementation of energy management would reduce the costs on energy by means of systematic control over energy sources.The standards set the requirements to the energy control system.Based on these requirements, an enterprise can develop and implement energy policy, set goals, tasks and develop plans of activities in accordance with legislative requirements and information connected with issues of considerable use of energy.An energy management system allows enterprises to fulfill their liabilities, formulated in the policy, take measures, which are necessary for improvement of energy efficiency, and demonstrate the correspondence of the system with requirements of the standards [11].
Energy management is based on the "continuous improvement cycle" methodology "Plan-Do-Check-Act" (PDCA) (Figure 1), which is described in the following way [11]: • Planning (plan)-carrying out energy analysis and determination of basic criteria and parameters of energy efficiency, setting goals, tasks and development of plan of activities, which are necessary for improvement of energy efficiency according to the energy policy of the enterprise; • Doing (do)-implementation of planned activities in the sphere of energy management; • Checking (check)-monitoring and measurement of processes and key characteristics of operations, that determine energy performance in relation to the implementation of energy policy and the achievement of energy goals, and reporting the results; • Action (act)-taking the measures for continuous improvement of efficiency of activities in the sphere of energy and the energy management system.A PDCA cycle-based methodology allows enterprises to develop systems and processes that are necessary for improvement of energy effectiveness, including the consumption and utilization of energy [12].Implementation of this technology contributes to reducing the negative impact on the environment and lessens the energy costs due to A PDCA cycle-based methodology allows enterprises to develop systems and processes that are necessary for improvement of energy effectiveness, including the consumption and utilization of energy [12].Implementation of this technology contributes to reducing the negative impact on the environment and lessens the energy costs due to systematic control of energy resources by a set of interrelated elements, which are used for development and implementation of energy-saving policy, its goals and processes aimed at reaching this.The methodology is also used for taking measures for improvement of energy effectiveness, demonstrating correspondence of energy system to the requirements of standards.That is why it is recommended to use the PDCA methodology, which is also known as the cycle of continuous improvement of processes, which incorporates all aspects of energy management into daily organizational practices.

Literature Review
The term energy effectiveness includes energy utilization, energy efficiency and energy consumption.Consequently, the enterprise, implementing an energy management system, can choose a course of action for itself from activities related to energy effectiveness.For example, it can decrease maximum load (maximum power need), use the extra energy or secondary energy resources, or improve operation of its energy system, processes and equipment [13][14][15].Important conditions for the achievement of competitiveness of an enterprise are the development and introduction of practice-oriented methods for supporting managerial decisions that would make it possible to manage the energy efficiency of an enterprise as a social intellectual system [16].
There are typical energy consumption strategies, which can be used for strategic planning [23]: -Passive strategy.Energy consumption management is not considered as a separate target.The tasks of energy policy development and application of international standards of energy management are auxiliary in searching for ways to survive for an enterprise in an environment of increased competition.-Profit-maximizing strategy in short-term period.The directorship takes measures with small payback period and high rate of return, choosing well-known efficient standard solutions, the implementation of which does not require additional obstacles like additional training of employees or increasing the efficiency of introduction of new technologies.-Profit-maximizing strategy in a long-term period.The directorship has solid understanding of market prices on energy sources and technology development, so it takes into consideration the projects with high payback periods of investments.-Strategy of implementation of all attractive investment measures.The directorship takes all possible measures in the sphere of optimization of energy consumption, which have positive economic effect in short-term and long-term perspective.
Factors determining the success of projects on energy management, have greatly changed over the last few years; new tendencies of development of energy-saving technologies have appeared.The main difficulties that should be noted include: low incentives for investment in energy saving, long payback periods, limited funding, increased costs of energy audit services.Oil-production enterprises do not fully use cost optimization methods for energy-saving measures and energy inspection, they do not take into account employees' motivation, and they do not pay attention to design and process approaches for development of an efficient energy-saving management system.We think that the main aspect of increasing the energy efficiency of oil production enterprises is the organization of energy saving [24].
The purpose of the work is to substantiate and develop methodological support for the formation of an organizational mechanism for managing energy saving at an oilproduction enterprise.

Materials and Methods
Assessment of energy saving potential of industrial enterprise of any country begins with analysis of energy policy and energy consumption directions and structure.
PJSC Rosneft is one of the biggest consumers of fuel and energy resources (FER) in the Russian Federation.The total volume of consumed FER for 2020 reached 18.9 million tons of fuel equivalent or 2749,33 million euros.Table 1 shows the distribution of energy consumption and energy costs in 2020 by areas of production [25].In the energy-saving program of PJSC Rosneft for 2021-2024 it is planned to carry out the measures to increase the efficiency of use of electric and thermal energy by main areas of production activities.The actual saving of FER for the year 2020 is shown in Table 2 [26].According to the policy of Rosneft, aimed at improvement of energy efficiency and energy saving, and the company's standard "Energy management system.Requirements and guideline for use", the next measures were taken in 2020 [25,26]: the regulations for work with the module "Energy efficiency of electric submersible pump units" of the information system "Mekhfond" were developed.Firstly, this has allowed introduction of the control procedure of energy efficiency of electric submersible pump units in the process of exploitation of producing wells.Secondly, it has allowed carrying out energy saving measures over time, without equipment failures or loss of geotechnical jobs; • the process of corporate training with five energy efficiency courses was organized.In 2020, 471 employees finished studying; • order No. 71 of PJSC Rosneft "On the development and implementation of targeted programs for the implementation of an information system for monitoring energy consumption at oil refining and petrochemical enterprises", dated 3 February 2020 was put into effect.This order involves formation of an automated instrument base for accounting of fuel and energy resources and the creation/implementation of corporate software for regulation, planning and reporting of energy consumption; • corporate check of energy management system of "Exploration and production" business unit was carried out.Individual roadmaps to achieve an improvement of detected disadvantages were prepared; • an internal audit of energy efficiency of 386 technological objects and units was carried out by its own personnel-energy-saving and energy efficiency departments, in order to find the potential of energy saving and its implementation in terms of the energysaving program; • 42 enterprises of the company were certified to the ISO 50001 "Energy management system".
Selection of optimal well operation methods is one of the main technological tasks of oil recovery by means of an artificial lift.Specific energy consumption can be adequately assessed by means of control, on the basis of which accurate calculations can be undertaken, determining the economic, technical and technological features of the operation method for a particular well [27][28][29][30][31][32].
The main directions to increase energy efficiency of the operation of the artificial lift well stock are: Technical measures: - Organizational measures: creation of an organizational structure at the enterprise that has the authority to effectively solve problems in the field of reducing energy consumption.Its functioning is based on the involvement of the maximum number of specialists in the process of saving energy, starting with the shop personnel and ending with the top managers of the enterprise, with an incentive to achieve the final result, a clear delineation of areas of responsibility; -training of corporate specialists with receiving a certificate for carrying out internal audits of energy management system in accordance with the requirements of international standard ISO 50001.
For calculation and control of energy efficiency, specific energy consumption (SEC) was selected as the main parameter.Specific energy consumption reflects energy output ratio with actual/planned parameters of electric energy consumption on the artificial lift of fluid and fulfillment of geotechnical works.
Methodology of energy planning consists of the following: The first (base) year-actual SEC is calculated, geological and technical factors are taken into account and analyzed.
The second year-the program of energy-saving measures is formed for the calculation period, economy of energy is calculated.
The third year-having taken geological and technical factors into account, the planned value of SEC is set.
On the basis of the results, the deviation of actual values from the planned ones is analyzed and SEC is corrected.
The fulfilled analysis of artificial lift well stock has allowed us to develop energysaving measures and show the results from their implementation (Table 3).The whole complex of described measures has allowed us to achieve excellent results in the area of energy efficiency improvement.Energy saving on fields of Udmurtia has increased from 15% to 43%, and specific consumption of energy for fluid lifting has been reduced by 2-4 times.In today's situation, energy efficiency is increased by means of implementation of technologies with minimal investments.Most low-cost technologies with high economic indicators have low technological efficiency with limited application possibilities and are able to reduce energy consumption by up to 10%.To achieve a significant effect, it is required to widely introduce the technologies that have both high technological and economic efficiency.However, there is a potential for optimization.

Results
All in all, the approach of Russian oil-production enterprises to the formulation of energy policy can be assessed as a strategy of implementation of all investment-attractive measures.The analysis of studies has allowed us to determine the main constraints to implementation of a policy of increasing the energy efficiency at oil-production enterprises and propose the main ways to improve the organization of energy saving (Figure 4).poer pumps; -Accounting heat energy operation costs The whole complex of described measures has allowed us to achieve excellent results in the area of energy efficiency improvement.Energy saving on fields of Udmurtia has increased from 15% to 43%, and specific consumption of energy for fluid lifting has been reduced by 2-4 times.
In today's situation, energy efficiency is increased by means of implementation of technologies with minimal investments.Most low-cost technologies with high economic indicators have low technological efficiency with limited application possibilities and are able to reduce energy consumption by up to 10%.To achieve a significant effect, it is required to widely introduce the technologies that have both high technological and economic efficiency.However, there is a potential for optimization

Results
All in all, the approach of Russian oil-production enterprises to the formulation of energy policy can be assessed as a strategy of implementation of all investment-attractive measures.The analysis of studies has allowed us to determine the main constraints to implementation of a policy of increasing the energy efficiency at oil-production enterprises and propose the main ways to improve the organization of energy saving (Figure 4).
human factor in implementation of energy saving projects employees' motivation assessment and management absence of efficient system of energy saving management design-process approach with identification of energy saving processes and their integration into the system of business processes high risk level of energy saving projects accounting and assessment of energy saving risks high-cost energy saving programs development of energy saving programs on the base of complex approach and cost optimization organization of energy saving at oil production enterprises Proposed methodological support for improvement of the energy management system and measures that are used for development of the organizational mechanism of energy saving management at oil production enterprise are shown in Table 4.   4 shows the generalized classification of measures, technical and economic indicators of efficiency of energy-saving on a strategic level that should be implemented by oil-production enterprises in the energy-saving sphere.
The following scheme is proposed for the formation of energy saving programs (Figure 5).The energy efficiency indicators of the organization of production include the specific energy intensity of the production space: The energy efficiency indicators of the organization of production include the specific energy intensity of the production space: where E-specific energy intensity of the production space, GJ/m 2 ; Q-amount of energy spent to support activities of industrial unit, GJ (or kW•h); S-area of industrial unit, m 2 .Key energy efficiency indicators include: share of use of secondary thermal energy in the main and auxiliary production; -growth of fuel combustion heat, intensification of fuel use; -specific energy consumption per year; -share of energy costs in prime cost of production (energy intensity); -reduction of emission; -average energy consumption per crew per shift; -efficiency of investment into internal energy projects, aimed at energy saving; -implementation of technological innovations in energy saving.

Conclusions
For oil-producing enterprises, the issues of optimizing energy costs are among priorities, since the economic profitability of an enterprise greatly depends on how efficiently energy resources are spent.One of the most effective mechanisms are the implementation of energy-saving technologies and an increase in the energy efficiency of the artificial lift of oil.
Relevant scientific results include the following: 1.
The main constraints on the implementation of the energy efficiency policy at oilproducing enterprises have been identified and directions for improvement of energysaving structures have been proposed.

2.
We have proposed strategic-level classification of energy-saving measures, which is based on assessment and comparison of implementation costs, payback period and takes into account investments into artificial lift technology, thereby allowing us to discern the investment priorities in the energy management sphere.

3.
Advanced directions for investment in oil-production technology have been identified, and an algorithm for development and implementation of key indicators of energy consumption efficiency has been proposed.
The proposed directions of energy saving and energy efficiency improvement for oil production promise to have a great economic impact.Analysis of results shows that the effect from implementation of the organizational mechanism of energy saving management at one enterprise from energy policy reached 40 million rubles over three years.

Figure 3 .Table 3 .Figure 3 .
Figure 3. Analysis of the conducted energy efficient measures on the artificial lift well stock in JSC "Samotlorneftegaz".Table 3. Directions of energy saving and increasing energy efficiency in oil production.Energy-Saving MeasuresResults from Implementation

Figure 4 .
Figure 4. Constraints and ways of improvement of organization of energy saving at oilproduction enterprises.

Figure 5 .
Figure 5. Scheme of formation mechanism of energy-saving programs at an oil-production enterprise.

Figure 5 .
Figure 5. Scheme of formation mechanism of energy-saving programs at an oil-production enterprise.

Table 1 .
Distribution of energy consumption and energy costs in 2020 by areas of production activity.

Table 2 .
Actual saving of fuel and energy resources for 2020.

Table 3 .
Directions of energy saving and increasing energy efficiency in oil production.

Table 4 .
Measures aimed at improvement of energy management system.