Application of Green Technologies in Irrigation

The article presents materials which reveal the using of green technologies (renewable energy sources) at the site of the irrigation complex of agriculture. In the article an option for placing solar panels on the Prigorodny irrigation system of the Krasnodar Territory of the Russian Federation is proposed to cover the power consumption of the units of the head pumping station PS 1 23. Engineering, technical and economic calculations of design, installation, and placement of solar panels of two types with a capacity of 200 watt were carried out. According to the application of Russian solar panels, the investment requirement is 1,845 billion rubles, with a payback period of 10, 2 years. Organizational and legal tools for attracting investments in the land reclamation complex of the country's agriculture using the mechanism of public-private partnership and the infrastructure of land reclamation parks is justified.


Introduction
The development of the world food market is proceeding in rather difficult conditions, in the midst of contradictions between the main actors in this processthe leading countries of agricultural production [1,2]. The government of the Russian Federation has adopted the export strategy, according to which the country should strengthen its presence in the world food markets by 2050 "conquer" a segment of 15%. The solution of this problem lies in the development of water and land resources through the using of innovative agricultural technologies. One of the institutional and infrastructural objects which can speed up the process of agricultural production is the Land improvement Parks (hereinafter -L.I.P.), a model of which was developed by Russian scientists. [3,4]. A L.I.P is a territorial, technological, technical, scientific base, provided with the necessary administrative and legal conditions for the development of land reclamation and the production of agricultural products. The main investor of the L.I.P is the state, which invests funds from the federal and regional budgets in the construction, reconstruction, technical reequipment of reclamation systems. Residents of the L.I.P. are agricultural producers after the commissioning of reclaimed land, reimburse the state 30% of the invested funds within 7 years [4].
One of the important aspects of agricultural production at the site of the L.I.P. is using of green technologies and improving energy efficiency. Renewable or "green energy" is energy that is obtained through processes occurring in the environment. In 2019, 28% of global energy consumption came from renewable energy sources (hereinafter referred to as renewable energy) [5].One of the components of RES is solar generation, based on the conversion of electromagnetic solar radiation into electrical or thermal energy. European Electricity Association «Eurelectric» has published in «Power Barometer» key indicators that reflected the development of the energy sector and identify the risks posed to building a climate-neutral European economy by 2050. «Barometer» shows that by 2030, the number of EU countries that will not have coal-fired generation will reach 21 [5]. According to Bloomberg NEF experts, the gap between solar and wind energy will grow. According to their forecasts, from 130 to 170 GW of solar capacities will be built annually against 50-60 GW of wind power. In total, the installed capacity of green energy (including hydropower) at the end of 2019 amounted to about 2, 5 TW [6]. The main RES producers are China, Great Britain, the USA and Germany (20 GW) [6]. To promote renewable energy sources, the government of the Russian Federation has developed an Action Plan to stimulate the development of generating facilities based on renewable energy sources with an installed capacity of up to 15 kW. The positive aspects of using RES include: inexhaustibility, environmental friendliness, speed of construction, low cost of energy received during operation. Negative aspects are: dependence on weather conditions and geographic location, low efficiency. At the same time, in 2020, a consortium of German scientists announced the development of solar panels based on perovskite and silicon with an efficiency of 33%, which is 50% better than the current record for solar panels of 22,3% [6]. The efficiency and feasibility of converting solar energy into electricity and heat largely depends on the potential of the territories. For example, in regions with a high potential for solar radiation, the creation of tower and modular power plants and solar power plants using solar E3S Web of Conferences 247, 01050 (2021) https://doi.org/10.1051/e3sconf/202124701050 ICEPP-2021 ponds in conjunction with wind power plants (WPP) allows these regions to be provided with electric energy by 95%. In the South of Russia and the southern part of Siberia, the annual number of sunshine hours makes it possible to use solar generation quite effectively. In these regions, due to high solar radiation and a large number of hours with sunshine, the using of solar power can be significantly cheaper than the cost of 1 kWh of thermal energy used from a thermal power plant (hereinafter referred to as TPP). In the global economy, there are examples of using of solar energy in irrigation facilities. For example, in the state of Gujarat, India, the state-owned generating company «Mahagenco» has placed solar panels above irrigation canals and uses the resulting energy to supply water to farmers [7].
The placing solar panels over irrigation canals ensure the implementation of several goals: reducing capital costs by placing solar panels above irrigation canals (saving on the allocation of land for development); reduction of water loss from water bodies by reducing evaporation; cooling of panels due to the water surface; obtaining clean energy; creation of new jobs. The purpose of the study is to consider the possibility of using green technologies at irrigation facilities based on the economical mechanism of public-private partnership.

Materials and methods
The article presents engineering and technical, economical and mathematical calculations to justify the placement of solar panels over irrigation canals in the South of Russia. A Prigorodny irrigation canal (PIC), which is part of the Kuban melioration system, was chosen as the object. The using of monitoring methods, comparative analysis, regulatory, computational and constructive modeling made it possible to justify the implementation of a project to create a solar generation complex over an irrigation facility using the mechanism of public-private partnership.

Results and reasoning
The Krasnodar region of the Russian Federation, due to its physical and geographical position (coordinates: 43° 30'-46° 30' N, determines the height of the sun above the horizon, the angle of inclination of the sun's rays from 68 ° 33 'at noon on June 22 to 21° 30° -22 December), has a lot of sunshine. Annual amount of heat in the north of the region is 115, and in the south -120 kcal/cm 2 . In summer, the total radiation is 48 and in winter -up to 12 kcal/cm 2 , except for the winter period, in all other periods of the year there is a positive heat balance, more than 45 kcal /cm 2 . The height of the sun in winter is less than 30°, from March to September -more than 45°. The duration of the sunshine is 2200-2400 hours per year; the average duration of sunshine per year is 2174 hours, while the annual maximum is observed in July (323 hours), and the minimum -57 hours in December, which indicates the economic feasibility of using green technologies -RES (table 1) [8,9].
There are 16 irrigation systems in the Krasnodar Territory, including: Fedorovskaya, Temryukskaya, Kryukovskaya, Prigorodny. The functioning of the irrigation system is ensured by the State Institution "Management of Land Reclamation and Water Management of the Krasnodar Territory" (hereinafterthe Kubanmeliovodkhoz Institution), which is under the jurisdiction of the Ministry of Agriculture of the Russian Federation [8]. The main activity of the Kubanmeliovodkhoz Institution is to create the necessary conditions for increasing the production of high-quality agricultural products based on the restoration and increase of soil fertility of agricultural lands while performing a complex of irrigation, drainage, cultural, water management, and organizational measures during the operation of irrigation systems [9].
The economic activity of the organization consists of funds allocated from the federal center and payments for services provided, the main of which is the supply of water by agricultural producers. The Kubanmeliovodkhoz Administration spends up to 78% of the allocated federal money to pay for electricity for the operation of pumping stations. One of the possible options for reducing the costs of the organization is to obtain energy from solar energy panels (placing solar panels on one of the main canals). The aim of the research was to determine the section of the main irrigation canal for the placement of solar panels. The most preferred place was the Prigorodny irrigation system, built in 1985, located in the northeastern Prigorodny part of the city of Krasnodar. The irrigation system serves 18 large water users of various organizational and legal forms of ownership (CJSC, LLC, SEC), as well as owners of personal subsidiary farms. The irrigation zone of the Prigorodny irrigation system includes agricultural fields of SEC «Krasnodarskiy», agricultural firms of «Solnechnaya». The main water intake for the system is carried out from the headwaters of the Krasnodar reservoir by pumping station № 1, and water is discharged through the Azov rivers Kochety and Ponura. The total irrigated area in the main canal zone is 23, 3 thousand hectares. Placing solar panels above the irrigation canal, it was necessary to solve a number of organizational problems: to identify the prospective customers, investors, contractors and  I  П  III  IV  V  VI  VII  VIII  IX  X  XI  XII  Average  71  83  130  181  242  289  323  291  239  173  95  57  Maximal  166  131  187  255  337  362  393  363  317  253  167  131  Minimal  27  37  79  100  159  200  252  214  161  108  43  18  Year  1967  1924  1924  1955  1915  1917  1925  1976  1929  1914  1955  1927 consumers. The research shows that the Project can be implemented on the basis of a public-private partnership mechanism and the infrastructure of a L.I.P [10, 11]. The organizational and legal form of the Project implementation can be a L.I.P. created on the basis of voluntary participation of partners, whose members can become 23 water users (18 large farms, owners of personal subsidiary farms). The benefit is that the energy received from the solar panels will remain the property of the residents of the L.I.P., which will reduce the level of payment of water supply to the fields. As a result of the implementation of the Project, the Kubanmeliovodkhoz Administration will be able to reduce its costs of purchasing energy from generating companies, and to form an optimal price for water supply, taking into account the interests of the L.I.P. residents. According to the Project, during the growing season (180 days), 90% of the generated electricity will be used to ensure the operation of the pumping station, the remaining period (185 days); the energy comes from solar generation, can be used by the members of the cooperative for their own needs or sold outside [12].

Project implementation
The main canal of the Prigorodny irrigation system has the following characteristics: safety level is satisfactory, the state of the channel -concrete and earthen; the technical assessment of the channel is satisfactory. The total capacity of the head pumping station (hereinafter -MPS) HC-1 23. 4 m 3 /s, the power consumption of all units is 4535 kWh. The pumping station is equipped with 7 pumping units with efficiency 3. 2 m 3 /s, with capacity of electric motor 630 kWh. There is also a standby unit of the brand OB6-55 with efficiency 1 m 3 /s, with capacity of electric motor 125 kWh. Pumping station HC-1 has been in operation since 1978 without replacement of equipment, as a result, the real energy consumption exceeds the design. The total irrigation area of the irrigation system according to the design data is 23 940 hectares, and irrigation in 2020. was produced only on an area of 5.888 hectares [11,12]. The considered section of the main canal originates between the «Znamensky» dacha partnership and the Prigorodny settlement and ends in the area of the Lazurny settlement (from the third head of the canal to the eighth the project section is 22, 75 km long. The channel width at the top is 12 m, which can be taken as the width of the placement of solar panels. The total area of the panels placement is 273 000 m 2 (table 2).
The layout of solar panels for the project under consideration is shown on the Fig. 1.
The calculation of the efficiency of the Project was based on the calculation of the power consumption of the head pumping station for the growing season (operating time of the canal) and the cost of electricity consumed by it (the calculation of the cost of electricity required for the MPS was carried out at the tariff of the second half of 2019, 5.59 rubles per kWh); the number of solar As a result of a preliminary calculation, it was established that the cost of electricity for the MPS during the operation of the channel, and therefore the amount of savings in the case of using solar panels, will amount to 109, 51 million rubles during the year. The cost of electricity generated in the winter (for 617 hours) for the needs of the population will be 35, 79 million rubles. Consecuently, with the total cost of installing the KCM-200 panels (1 415, 5 thousand rubles) and CHN 200W-72M panels (760, 6 thousand rubles), the payback period will be 10, 2 years and 6,6 years, respectively.

Findings
The use of renewable energy sources is one of the promising areas in the world economy, which allows to reduce the cost of production in agriculture. To promote renewable energy sources into the national economy, the Government of the Russian Federation has developed an Action Plan to stimulate the development of generating facilities based on renewable energy sources with an installed capacity of up to 15 kW [6]. The implementation of this plan will make it possible to simplify the process of placing solar generation facilities, will provide their owners with the opportunity to sell surplus generated electricity to the general grid. The calculation results of the Project shows that solar panels placed above the main canals can be quite effective. The use of the mechanism of public-private partnership at the site of the L.I.P. allows accumulating funds of investors to provide water users with cheaper energy, which makes it possible to form a lower price for payment of water supply services.