Potential Assessments for Local Renewable Energy Resources of Arkhangelsk Region

Degtyarev Kirill Stanislavovich ORCID: 0000-0002-1738-6320 PhD in Geography lecturer; Department of Geography Faculty, NIL of Renewable Energy Sources; Lomonosov Moscow State University Researcher; Lomonosov Moscow State University; Faculty of Geography; NIL of Renewable Energy Sources 119991, Russia, Moscow, Leninskie Gory str., 1, office 19 kir1111@rambler.ru Other publications by this author     Berezkin Mihail YUr'evich ORCID: 0000-0002-6945-2131 PhD in Geography Senior Researcher; Faculty of Geography, Research Laboratory of Renewable Energy Sources; Lomonosov Moscow State University 119991, Russia, Moscow, Leninskie Gory, 1 mberezkin@inbox.ru

Sinyugin Oleg Anatol'evich ORCID: 0000-0001-5874-4342 PhD in Economics Senior Researcher; Faculty of Geography, Research Laboratory of Renewable Energy Sources; Lomonosov Moscow State University 119991, Russia, Moscow, Leninskie Gory, 1 sinyugin.oleg@yandex.ru

introduction

The development of energy based on renewable energy sources (RES) in Russia remains an urgent task. On the one hand, this directly follows from Russia's accession to the Paris Climate Agreement ^[1] and the adoption of a program for the socio-economic development of a country with low greenhouse gas emissions ^[2].

Another aspect is related to the need to increase the energy supply of the country's regions, primarily energy–deficient and remote territories, in order to ensure sustainable energy and, as a result, socio-economic development. In this case, relying on local renewable energy resources may be economically more profitable than supplying energy from other regions.

In recent years, the solar and wind power industry has been developing most actively in our country; at the same time, the bulk of the capacity is concentrated in the south of Russia ^{[3; 4]}. The northern regions, with obviously smaller solar and, in most cases, wind resources, are currently out of focus on renewable energy, at least on a kind of information periphery. Meanwhile, the northern territories of Russia have their own range of renewable energy sources, due to natural and climatic conditions and the specifics of the economy, which can play a significant role in energy supply.

In this article, the renewable energy potential of the northern Russian regions is considered on the example of the Arkhangelsk Region (excluding the Nenets Autonomous Okrug), one of the largest in terms of area and population of the subjects of the north of the European part of the country. The main object of assessment is the wood waste of the timber processing complex. At the same time, attention is also paid to other local renewable energy resources of the territory, due to its climate and geographical location.

The purpose of the work is to identify the possibilities for the development of energy in the region based on local renewable energy sources, as well as to identify areas of the Arkhangelsk region where it is most in demand.

The information and methodological base of the work is data from federal, regional and sectoral statistics and analytical materials, the results of previous studies of the natural resources of the region, in particular ^{[5, 6, 7]}, currently existing methodological developments and guidelines for determining the potential of renewable energy resources ^{[8, 9, 10]} and the authors' own developments related to the study of renewable energy resources of the regions and their typologization ^{[11, 12, 13]}.

PROBLEMS OF ENERGY SUPPLY

NATURAL AND ECONOMIC ENERGY RESOURCES AND PROBLEMS OF ENERGY SUPPLY

The Arkhangelsk Region (Fig.1), excluding the Nenets Autonomous Okrug (NAO), covers an area of 413 thousand ^km2 and has a population (estimated on 01.01.2024) of 956 thousand people, including urban – 747 thousand, rural – 209 thousand ^[14]. More than 30% of the total population and 40% of the urban population - 300 thousand people, live in the capital of the region, Arkhangelsk; together with Severodvinsk and Novodvinsk, the total population of the metropolitan agglomeration is more than 500 thousand people, or more than half of the population of the region.

Among the main features of nature and geographical location, significant from the point of view of assessing renewable energy resources, it should be noted:

- the territory of the region lies in a temperate climatic zone; a zone of temperate continental climate with elements of a subarctic climate in the north; in a zone of excessive moisture, it has a dense and extensive hydrological network (the average density of the river network is 0.61 km/^{km2 [15]}; the annual volume of local river flow is more than 140 km3 per year, or an average of 350,000 ^m3/^km2 per year; the region belongs to territories with high river water content ^[16]);

- the territory of the region lies in a forest zone (a subzone of the northern taiga), has large forest resources; the forest occupies 54% of the area, the forested area is more than 220 thousand ^{km2 [17]}, and forest resources are estimated at about 2,700 million. ^{m3 [18]}, an average of 65 ^m3/ha of the region's area, or 120 ^m3/ha of forest area;

- The Arkhangelsk region is a flat area with individual elevations with an absolute height of up to 350, most of them up to 250 meters;

- The Arkhangelsk region has access to the White Sea.

Fig. 1. Map of the territorial and administrative division of the Arkhangelsk region ^[19]

The climate of the Arkhangelsk region in most of the territory can be characterized as moderately marine in most parts, moderately continental in the southeastern regions and subarctic in the far northeast. Average air temperatures rise from the northeast to the southwest of the region: January from -18 ⁰ C to -12 ⁰ C, July from 10 ⁰ C to 17 ⁰ C. The average annual precipitation is from 400 to 600 mm with an average moisture coefficient from 1.4 to 1.5. The weather is unstable due to the combination of the influence of the Arctic Ocean and the Atlantic. There is a high frequency of extreme weather events, such as strong winds, snowstorms and rains, mainly in the coastal parts of the region. At the same time, during the second half of the XX – beginning of the XXI century, trends towards a decrease in the frequency of extremely strong winds and snowstorms are recorded simultaneously with an increase in precipitation ^{[20, 21]} and climate warming.

Previously, it can be concluded that the Arkhangelsk Region, due to its latitudinal position and weather conditions, does not have a high potential for solar energy, and wind energy is concentrated mainly in coastal areas. The Arkhangelsk Region is characterized by a dense hydrological network and large volumes of river runoff (see above), which makes it possible to consider its hydropower prospects; at the same time, small elevation differences and freezing of watercourses in winter for a long time are constraining factors. It should be noted that the weather and climate changes noted above generally increase the potential of renewable energy sources in the region and create more favorable conditions for their use.

The most obvious and accessible are the bioenergy resources of the Arkhangelsk region associated with forest and waste from the timber processing complex, as well as peat deposits and peat processing.

When analyzing the volume, structure and problems of energy supply in the Arkhangelsk region, thermal energy and electric power should be separated.

As of the end of 2023, the thermal power industry of the Arkhangelsk Region is represented by 613 boiler houses ^[22], including 4 cogeneration plants (TPPs) with a total number of boilers (power plants) equal to 1721. The main part of boiler houses is accounted for by small ones (Table. 1), including 449, or 73% of the total number – for boiler houses with a capacity of up to 3 Gcal/h, located mostly in rural areas – 396 boiler houses, or 65% of the total number.

However, the total capacity and production of thermal energy are concentrated on large installations located in cities and serving the urban population and large industrial consumers. The 4 largest thermal power plants of the Arkhangelsk region – the Arkhangelsk CHPP, the Severodvinsk CHPP group, as well as the CHPP of the Arkhangelsk and Kotlas Central Processing Plants, account for about 6040 Gcal/h, or 73% of all installed thermal capacities and 11,500 thousand Gcal, or 64% of the total heat produced (in 2023).

In turn, boiler houses in rural settlements account for 800 Gcal/h, or 10% of all installed thermal power capacities, and 877 thousand Gcal, or less than 5% of the total heat produced.

Table 1. Thermal energy production in the Arkhangelsk region, 2023 ^[22]

Local types of biofuels (firewood, wood chips, wood fuel pellets) and imported energy carriers are used as fuel in boilers: coal, natural gas, fuel oil. In the region, there is an active process of transferring thermal capacities to local types of wood fuels, primarily waste from the LPC and pulp and paper industry (lye). Thus, from 2007 to 2016, the share of imported fuel in the consumption of regional municipal energy decreased from 57% to 29%, and the share of local bioresources increased from 18% to 42%; according to the situation in 2018, more than 50 boiler houses were converted to biofuels. ^[23]. At the same time, it should be noted that oil and gas are produced in small volumes on the territory of the Arkhangelsk region, therefore, the replacement of imported resources with local ones may also include an increase in the share of local fossil energy carriers.

According to data for the middle of 2023, 334 boiler houses in the Arkhangelsk region used firewood as the main fuel, 40 – wood fuel, 8 – pellets (i.e. 62% of the boiler houses in the region operate on biofuels). The annual demand of boiler houses for firewood was estimated at 546 thousand ^m3, in wood fuel – 362 ^m3, in pellets – 14 thousand tons ^[24].

Data on energy consumption by type (Table. 2) show that 92% of energy resources for heat production in the Arkhangelsk region are consumed in cities, while the structure of production by sources differs markedly between urban and rural areas. On average, more than half of the heat in the region is produced by natural gas, which accounts for most of the region's thermal power plants (Table), but in cities its share is 56%, and in villages – 6%. Another major source is solid fuels (including both wood and coal), which account for an average of 46%, 42% in cities, and 91.7% in villages.

Table 2. Fuel consumption by type of heat production, 2023 ^{[22; calculations by the authors]}

In the absence of direct data on coal consumption in coal-fired boilers, we can, based on indirect information about the needs of wood-fired boilers (see above), estimate the energy equivalent consumption of wood material (about 500 thousand tons per year) at about 2000-2500 million kWh. - only 25% of solid fuel and 10% of the total consumption structure. This is consistent with other estimates, according to which up to 86% of primary energy resources consumed are imported to the Arkhangelsk Region from other regions ^[5] – mainly coal and gas.

There is also data on the supply of coal at the beginning of the XXI century, according to which, the volume of supplies of only Intinsky coal (Vorkuta basin) to the Arkhangelsk region amounted to 1 million tons ^[25], which is also consistent with the above estimates. It is obvious that currently there is a reduction in the volume of supplies and the replacement of coal with local fuels – mainly wood, but imported solid fuels still play a significant role in the energy supply of the region - at least in urban heating systems.

Thus, the process of replacing coal with biofuels is mainly at the level of small boiler houses, as a result of which, although most boilers currently operate on biofuels, its total weight in the structure of energy consumption is inferior to both gas and coal.

In parallel, the process of converting coal-fired boilers of the Arkhangelsk region to gas is underway, as reported by a number of regional media; the Arkhangelsk region is also included in Gazprom's gasification program. There is a continuing low level of gasification in rural settlements in the region.

There are also plans to further increase the share of wood pellets in heating. So, in the near future it is planned to build 20 new pellet boilers with a total consumption of 25 thousand tons of pellets per year ^[26] – however, such an amount does not fundamentally change the structure of energy consumption in the region in favor of local renewable resources.

Firewood also plays a significant role in heating private households in the Arkhangelsk region. According to ^[27], the annual volume of firewood harvesting in the Arkhangelsk region is about 700 thousand m3, i.e. about 150 thousand m3 of firewood is sent not to boiler houses (see above), but to private households. According to some data, firewood accounts for more than a third of all energy resources of the region involved in municipal energy ^[28].

The electric power industry of the Arkhangelsk Region is represented primarily by 10 large thermal power plants (TPPs) with a total capacity of 1,605 MW (Table 3). This assessment does not include the thermal power plants of the Solombalsky Central Bank, declared bankrupt, information about which is not available in open sources. Almost all the capacities are grouped in the Arkhangelsk agglomeration (Arkhangelsk, Novodvinsk, Severodvinsk), some of them in the Kotlas – Koryazhma agglomeration.

Table 3. Power plants of the Arkhangelsk region ^{[29; 30; 31]}

A significant part of them – about 600 MW of capacity, or almost a third, belong to large timber processing and pulp and paper holdings, and work, to a large extent, for the energy supply of enterprises that are the largest consumers of the region (Table 4).

Table 4. The largest consumers of electric power capacity in the Arkhangelsk region ^[32]

The main part of the facilities was created during the Soviet period, starting in the 1960s. Initially, coal was the main fuel, but by now natural gas plays a leading role in the production of electricity, and in the last 10-15 years there has been an active involvement in the production of local bioenergy resources – waste from logging, woodworking and pulp production, as well as waste water.

Other types of power plants, such as nuclear power plants, hydroelectric power plants or other renewable energy plants, are currently absent in the region, as well as projects for the construction of new power plants. The construction project of the Mezen tidal power plant in the Mezen Bay of the White Sea (a "megaproject" with a capacity of up to 8000 MW), as well as wind farms in the region, is under discussion, but the start of these projects is unlikely in the foreseeable future.

In addition to large thermal power plants, 40 more diesel power plants with much lower capacity (the largest is the Mezen DES with a capacity of 7 MW) are located in the decentralized energy supply zone. Their total capacity is more than 40 MW, or 2.5% of the total capacity of all power plants. The use of DES in remote areas is a typical situation for the Arctic regions of the world ^[33], as well as the task of replacing or supplementing them through the use of local renewable energy sources.

In the Arkhangelsk region, until the early 1970s, there were more than 60 small hydroelectric power plants with capacities from 6.5 to 107 kW, which were replaced by cheaper diesel power plants (DES) at that time ^[5].

Most of the DES are concentrated in Leshukonsky and Mezen municipal districts with a permanent population of 6,000 and 8000 people, where 22 local DES with a total capacity of about 19 MW are located ^[5].

Electricity generation at all power plants in the Arkhangelsk region in 2023 amounted to 6,594 million kWh, while electricity consumption was 7853 million kWh. The deficit is 1,259 million kWh, or 16% of the energy consumption. In addition, most of the electricity is currently generated from fossil fuels supplied from other regions.

There is no data on the share of bio-waste in electricity production in the Arkhangelsk region. It follows from table 3 that about 50 MW, or 3% of the capacity, operate entirely on waste from timber processing, and another 650 MW, or 40%, operate partially on them. It can be assumed that, in fact, 10% -20% of the total electricity of the region, or 650-1300 million kWh, is produced due to waste from logging, timber processing, woodworking, pulp and paper industry, municipal waste.

The power system of the Arkhangelsk region (Fig. 2) is connected to the power systems of the Vologda Region by two 220 kV and four 110 kV transmission lines, the Komi Republic by one 220 kV and one 110 kV, the Kirov Region by two 110 kV overhead lines, the Republic of Karelia by one 110 kV overhead line. The electric power complex of the Arkhangelsk region also includes 18 220 kV voltage class transmission lines with a length of 1526.54 km and 130 110 kV lines with a length of 3816.05 km, the length of 35 kV lines is 2152.3 km.

Fig. 2. The electric power system of the north of the European part of Russia (ECO Northwest) ^[6]

Thus, the following problems exist in the energy sector of the Arkhangelsk region:

1) a high degree of dependence on energy supplies from other regions for both thermal and electric power industry;

2) shortage of electricity production (16%);

3) low energy consumption density due to power lines. The average is 200 people/km of 110-220 kV transmission line, whereas the average in Russia is 1.5 times more – 300 people/ km of 110-220 kV transmission line (based on the length of the transmission line and the population in Russia);

4) a relatively high proportion of the population living in energy-insulated areas. Despite the fact that energy consumption in these territories is slightly more than 1%, 9.5% of the rural population (or 2.2% of the total population) of the region live here ^[34];

5) the problem of wear and high accident rate of power grids ^{[32; 35]}.

ASSESSMENT OF RENEWABLE ENERGY RESOURCES

Currently, the most used and recoverable forest resources are. First of all, for the purposes of energy use, we can talk about waste from logging and timber processing.

The average volume of logging in the Arkhangelsk region in 2017-2023 was 14.2 million ^m3. ^[36]. The Arkhangelsk Region is among the top five regions of Russia in terms of logging volumes – it accounts for about 7% of all roundwood harvested in the country. A number of large logging and woodworking holdings operate in the region, such as Segezha Group, ULK Group, Ilim Group, Arkhangelsk Dock, Arkhangelsk Forestry Company and a number of others. As a rule, they follow the path of vertical integration with the creation of a single chain, including logging, sawmilling and the production of a wide range of finished products – building materials, furniture, pulp, paper, and forestry. In parallel, on the basis of enterprises of the timber processing complex (LPC), the production of wood fuel pellets (pellets) has been created. The total production capacity of wood pellets is approaching 700 thousand tons/year ^[37], although by the end of January-August 2024, only 50 thousand tons were produced in the region ^[38] Until recently, pellet production was focused mainly on exports to European countries; in the last few years, some development has also been received the domestic market, starting in 2022, against the background of sanctions blocking exports. In addition, other LPC wastes, mainly wood chips and sawdust, are used as a fuel source.

Currently, LPC waste is far from being fully used. According to ^[8], the standard for the export of logging waste, including twigs, branches, tops on a growing tree, for the Arkhangelsk region is the formation of branches and twigs of 16.6% of the volume of wood export.

Thus, with an average annual logging volume of 14 million ^m3, the amount of waste will be 14.2 million ^m3*16.6% = 2.36 million ^m3. With an average waste density of 530 kg/^m3, their total weight will be 1.25 million tons, which is twice the amount of wood waste currently used. In energy equivalent, with an average calorific value of 3,000 kWh/t, this is 3,750 million kWh. With the efficiency of heat generating plants equal to 80%, the production of thermal energy from this amount of waste will amount to 3,000 million kWh, or 2,580 thousand. Gcal, which is able to provide 14% of the current thermal energy production in the region (see Table 1).

If we consider these wastes as fuel for electricity production, then with a CHP efficiency of 30%, electricity generation will amount to 3750*30% = 1,125 million kWh, or 17% of current electricity production.

At the same time, twigs, branches and tree tops are not the only type of logging waste. According to estimates ^[9], the average mass of stumps and roots remaining at the cutting site is 112 kg/^m3 for coniferous trees (kg/131 ^m3 for deciduous trees). Thus, the minimum number of stumps and roots for this volume of logging will be 14.2 million ^m3 * 131 kg/^m3 = 1.86 million tons, which, under the above assumptions, is equivalent to the production of another 3,840 thousand tons. Gcal (21% of thermal energy production in the region) or 1,674 kWh of electricity (25% of current generation).

Additional volumes of waste are also generated during the bucking of wood (about 1.5-2% of the volume), sawmilling and the production of various types of finished products. Their value is difficult to determine, since it requires a detailed analysis of the existing structure and production technologies, but together they can be estimated approximately in the order of another 10-20% of the logging volume, or up to 1 million tons, which may be equivalent to the production of 2000-3000 million kWh, or 1700-2600 thousand. Gcal, i.e. another 14-17% of the amount of thermal and electric energy currently produced. At least some of the waste from LPC and CBK is currently used directly as fuel or for its production.

Thus, depending on the completeness of the extraction of LPC waste at a given volume of logging and timber processing, their combined energy potential is in the range 3 000 – 9 000 million kWh, or 2 600 – 7 700 thousand. Gcal, which is equivalent to 15-50% of the current production of thermal and electric energy, or 1.5-5 times higher than current figures.

It should also be noted that the size of the estimated cutting area – the maximum possible volume of annual deforestation in the Arkhangelsk region is almost 28 million. ^{m3 [39]}, which is almost twice the current volume of logging. Theoretically, the full use of the calculated cutting area is able to cover the energy needs of the region by half or even completely.

In addition to wood fuel, there is a wide range of renewable energy sources that are poorly used or practically unused in the energy sector of the Arkhangelsk region at the present time:

- peat deposits (at the same time, the expediency of widespread use of peat as fuel is currently a debatable issue);

- waste from animal husbandry and crop production;

- hydroelectric power of rivers;

- tidal energy;

- wind energy;

- solar energy.

Their potential requires clarification and additional research. Current estimates ^[10] show that the economic potential (according to the situation in 2007 – currently it may be significantly higher) of these sources collectively exceeds 50% of current electricity production (Table. 5), and the technical potential is many times higher than the entire volume of actual consumption of both thermal and electric energy in the Arkhangelsk region.

Table 5. Estimates of the annual renewable energy potential of the Arkhangelsk region ^[10]

In particular, in the coastal areas of the White and Barents Seas, the average annual wind speeds at an altitude of 10 m are 5-8 m/s ^[40], and the winter maximum wind intensity coincides with the winter maximum consumption of electric and thermal energy, which is an important prerequisite for the effective use of wind energy. The technical wind resources of the districts of the Arkhangelsk region with average annual wind speeds above 4 m/s are estimated at about 1,900 billion. kWh ^[41]. This is more than 200 times higher than the level of electricity consumption in the region.

The flow of incoming solar energy in the Arkhangelsk region averages 2.67 kWh/^m2 per year ^[42]. The maximum insolation occurs in May-July (4-5.8 kWh/^m2), which is quite acceptable for effective use. This makes it possible to use (with the proper level of assessment and design) hybrid generation stations. Calculations show that with an average electricity consumption of 7 thousand kWh/person per year in the Arkhangelsk region, about 180 million kWh/year will be required for the population living in energy-insulated territories. Taking into account the installed capacity coefficient achieved so far for wind farms and SES in these areas, the required capacity of renewable energy installations amounted to 250-350 MW.

ENERGY-INSULATED TERRITORIES

In energy-insulated territories, the use of local renewable energy sources is most in demand. They account for a relatively high proportion of the population of the Arkhangelsk region. As mentioned above, about 10% of the rural population (or 2.2% of the total population) of the region lives here.

Basically, the energy consumption of remote areas of the region that are not connected to the unified energy system is met by diesel power plants ^[32]. Along with the problem of the high cost of both the fuel itself and its transportation, there are environmental consequences of its use. Moreover, the Arkhangelsk Region belongs to the territories of the Far North with weak resistance of northern ecosystems to man-made loads.

Calculations of the area of such territories were made. They made up 19% of the entire territory of the Arkhangelsk region. They are home to 25.7 thousand people. This is 9.3% of the rural population and 2.1% of the total population of the region. The largest share of the rural population not connected to the unified energy system is in Leshukonsky (32%) and Mezensky (29.3%) districts, the easternmost and sparsely populated in the Arkhangelsk region. The smallest share is in Verkhnetoyemsky (4.3%) and Pinezhksom (4.2%) districts. There are four more districts where there is a rural population with decentralized energy supply – Onega (19% of the total rural population), Vinogradovsky (13.3%), Shenkursky (9.3%) and Primorsky (8.3%) ^[34].

At the same time, a critical factor hindering the economic development (including energy) of the rural areas of the Arkhangelsk region is a decrease in the population – in rural regions of the region it is about 2% per year and is associated with both negative natural growth and a large migration outflow ^[14]. Moreover, this factor can call into question the expediency of investing in these territories as such, since maintaining the existing rate of population decline in them means its complete disappearance over the next 50 years. This should be taken into account in all long-term development programs, including energy ones, and they themselves, as one of the key goals, should have the cessation or significant slowdown of depopulation of the territory.

conclusions

The production of thermal and electric energy in the Arkhangelsk region is carried out by 85%-90% on the basis of hydrocarbon, mainly imported energy carriers. The problem of the electric power industry is also a significant excess of electricity consumption over production. In recent years, there has been an active expansion of the use of local bioresources in the energy sector, primarily waste from logging, timber processing and the pulp and paper industry. Most of the boiler houses and a significant part of the thermal power plants operate on the basis of biofuels, however, these are mainly low-capacity installations, and therefore the share of local biofuels remains low.

The Arkhangelsk Region retains a high potential for increasing the production of thermal and electric energy based on logging waste. Depending on the completeness of the use of these wastes, their share, with the existing volume of roundwood harvesting, can range from 15% to 50% of the total production of thermal and electric energy at present. At the same time, based on the size of the estimated cutting area, the volume of logging can be doubled relative to the current level.

The Arkhangelsk Region also has a high potential for other renewable energy sources that are currently practically unused, including hydropower, wind energy (mainly in coastal areas), tidal energy in the bays of the White Sea, bioenergy based on agricultural waste, solar energy (in combination with other renewable energy sources or hydrocarbon fuels). Moreover, current climate changes are contributing to the growth of their potential.

Theoretically, the combined potential of renewable energy sources allows not only to fully meet the current needs of the region in thermal and electric energy, but also to increase its energy capacity.

The development of the electric power industry is most in demand, primarily in small autonomous forms, using local renewable energy resources in the energy-isolated territories of the region, which make up 19% of its area, where 25 thousand rural people live. At the same time, rural areas of the Arkhangelsk region are experiencing rapid depopulation associated with negative natural growth and a large outflow of population, which requires additional analysis and consideration when preparing projects and programs related to their development.