# Chapter VIII. Energy balances ## A. Introduction 8.1. Concept of energy balances. An overall energy balance (referred to as "energy balance" in the rest of the chapter) is an accounting framework for the compilation and reconciliation of data on all energy products entering, exiting and used within the national territory of a given country during a reference period. Such a balance must necessarily express all forms of energy in a common accounting unit and show the relationship between the inputs to and the outputs from the energy transformation processes. The energy balance should be as complete as possible so that all energy flows are, in principle, accounted for. It should be based firmly on the first law of thermodynamics, which states that the amount of energy within any closed system is fixed and can be neither increased nor diminished unless energy is brought into or sent out from that system.[^64] 8.2. Balances can also be compiled for any particular energy product (energy commodity) and, in these cases, are referred to as energy commodity balances or, for brevity, commodity balances. Commodity balances follow the general structure of energy balances but focus on single energy products and display some presentational differences (see section F of this chapter for details). 8.3. Purpose of energy balances. An energy balance is a multi-purpose tool to: (a) Enhance the relevance of energy statistics by providing comprehensive and reconciled data on the energy situation on a national territory basis; (b) Provide comprehensive information on the energy supply and demand in the national territory in order to understand the energy security situation, the effective functioning of energy markets and other relevant policy goals, as well as to formulate energy policies; (c) Serve as a quality tool to ensure completeness, consistency and comparability of basic statistics; (d) Ensure comparability between different reference periods and between different countries; (e) Provide data for the estimation of CO2 emissions with respect to the national territory; (f) Provide the basis for indicators of each energy product's role in a country's economy; (g) Calculate efficiencies of transformation processes occurring in the country (e.g., refining, electricity production by combustion of fuels, etc.); (h) Calculate the relative shares of the supply/consumption of various products (including renewables versus non-renewables) of a country's total supply/consumption; (i) Provide an input for modeling and forecasting. 8.4. The multipurpose nature of the energy balance could be further increased by the development of supplementary tables that combine information from the balance with additional information on particular issues that are not explicitly reflected in the balance itself. (see para. 8.50 for further discussion of this issue.) 8.5. Detailed and aggregated energy balances. Energy balances can be presented in both detailed and aggregated formats. The degree of detail depends on the policy concern, data and resource availability, and the underlying classifications used. The energy balance in an aggregated format is usually prepared for dissemination in printed form where the level of aggregation, that is the number of columns and rows, is mainly constrained by practical considerations. However, it is recommended that countries collect data at the level of detail that allows for the compilation of a detailed energy balance, as presented in table 8.1. When such a level of detail is not available or practical, it is recommended that countries, at a minimum, follow the template of the aggregated energy balance presented in table 8.2. ## B. Scope and general principles of energy balance compilation 8.6. The scope of an energy balance is determined, inter alia, by the territory, product and flow boundaries: (a) Territory boundary—defined by the boundary of the national territory of the compiling country (see chapter II for details); (b) Product boundary—defined by the scope of all energy products shown in the balance columns (see chapter III for details); (c) Flow boundary—defined by the scope of energy flows shown in the balance rows (see chapter V for details). 8.7. The product and flow boundaries are fixed in the short term. However, as technology advances, new sources of energy may become available and should be reflected in the balances when used. 8.8. The scope of an energy balance does not include: (a) Passive energy, such as the heat gain of buildings, solar energy falling on the land to grow crops, etc.; (b) Energy resources and reserves (which can nevertheless be considered in additional tables); (c) Extraction of any materials not covered in primary energy production (e.g. natural gas flared or vented). Data on some such materials are included in the data reference list (see chapter VI), and can be shown in an additional table; (d) Peat, waste and biomass used for non-energy purposes. 8.9. When compiling an energy balance, some general principles on the coverage and structure of the balance should be taken into account. These principles are as follows: (a) The energy balance is compiled with respect to a clearly defined reference period. In this respect, it is recommended that countries, as a minimum, compile and disseminate an energy balance on an annual basis; (b) The energy balance is a matrix represented by rows and columns; (c) Columns represent energy products that are produced and/or are available for use in the national territory; (d) The column "total" contains cells which provide the sum of the data entries in the corresponding row; however, the meaning of the cells in the "total" column is not the same for all rows of the balance; (e) Rows represent energy flows; (f) A separate row is reserved for statistical difference, calculated as the numerical difference between the total supply of an energy product and the total use of it; (g) The detailed energy balance should contain sufficient rows and columns to show clearly the relationship between the inputs to and outputs from transformation processes (production of secondary energy products); (h) All entries should be expressed in one energy unit (it is recommended that the Joule be used for this purpose, although countries could use other energy units such as tons of oil equivalent, tons of coal equivalent, etc.); the conversion between energy units should be through the application of appropriate conversion factors (see chapter IV) and the applied factors should be reported with the energy balance to make any conversion from physical units to Joules or other units transparent and comparable; (i) Net calorific values should be used for measuring the energy content of energy products. If gross calorific values are used in a country because of the recuperation of latent heat or for maintenance of historical data series, the corresponding conversion factors should be reported and countries should clearly identify which method is used; (j) To give a primary energy equivalent to electricity produced from non-combustible energy sources, the physical energy content method should be used. According to this method, the normal physical energy value of the primary energy form is used for the production figure. This is in contrast to the "partial substitution method" which requires assigning to such electricity a primary energy value equal to the hypothetical amount of fuel required to generate an identical amount of electricity in a thermal power station using combustible fuels. If the partial substitution method is used in a country, that country should clearly mention this, together with the average generating efficiency of thermal power stations used to calculate the primary energy equivalent. In the physical energy content method, the normal physical energy value of the primary energy form is used for the production figure. For primary electricity, this is simply the gross generation figure for the source. Care is needed when expressing percentage contributions from the various sources of national electricity production. As there is no transformation process recognized within the balances for the production of primary electricity, the respective percentage contributions from thermal and primary electricity cannot be calculated using a "fuel input" basis. Instead, the various contributions should be calculated from the amounts of electricity generated from the power stations classified by energy source (coal, nuclear, hydro, etc.). In the case of electricity generation from primary heat (nuclear, geothermal and concentrating solar), the heat is the primary energy form. As it can be difficult to obtain measurements of the heat flow to the turbines, it is recommended that an estimate of the heat input be used based on an efficiency of 33 per cent for nuclear and concentrating solar, and 10 per cent for geothermal as a default, unless country- or case-specific information is available. This means that, in the absence of measurements of the actual heat input, the equivalent primary nuclear or concentrating solar heat is estimated as three times the electricity produced, and the equivalent geothermal heat is estimated as 10 times the geothermal electricity output. (k) Production of primary and secondary energy, as well as external trade in energy products, stock changes, final energy consumption and non-energy use should be clearly separated to better reflect the structure and relationships between energy flows and to avoid double-counting. ## C. Structure of energy balance: an overview 8.10. Structure. An energy balance is a matrix showing the relationship between energy products (represented in columns) and flows (represented in rows). The structuring of an energy balance depends on a country's energy production and consumption patterns and the level of detail that country requires. However, it is recommended that certain common approaches, described below, be followed to ensure international comparability and consistency. 8.11. Columns. A column refers to a group of energy products. Each cell in this column shows a flow of energy involving this group of products, as defined by the row name. The number of columns depends, among other things, on whether the balance is intended for detailed analysis or is prepared for general dissemination (including printed publications) where space limitations have to be taken into account. In the first case, the energy balance may contain as many columns as needed, while in the second case it should be compact and contain columns that highlight energy products, especially important for the compiling country, as well as columns needed for international reporting and comparisons. Even when only a compact version of the energy balance is compiled and generally disseminated, a more comprehensive electronic version of the energy balance should be made available to users requiring more detailed information. 8.12. Sequencing of columns. While different columns (except "total") represent various energy products, they might be grouped and sequenced in a way that adds to the analytical value of the balance. In this connection, it is recommended that: (a) Groups of energy products be mutually exclusive and based on SIEC; (b) The column "total" follow the columns for individual energy products (or groups of products); (c) The column "total" be followed by supplementary columns containing additional subtotals such as "renewables". The definition of such subtotals and any additional clarification on the column's coverage should be provided in appropriate explanatory notes. 8.13. Rows. One of the main purposes of an energy balance is to reflect the relationships between the primary production of energy (and other energy flows entering/exiting the national territory), its transformation and final consumption. The number of rows and their sequencing in a balance are intended to make those relationships clear, while keeping the balance compact, especially when presented in an aggregated format. 8.14. Sequencing of rows. It is recommended that an energy balance contain three main blocks of rows as follows: (a) Top block—flows representing energy entering and leaving the national territory, as well as stock changes to provide information on the supply of energy on the national territory during the reference period; (b) Middle block—flows showing how energy is transformed, transferred, used by energy industries for own use and lost in distribution and transmission; (c) Bottom block—flows reflecting final energy consumption and non-energy use of energy products. 8.15. A separate row should be reserved for statistical difference and placed between the top and middle blocks of the balances. ### 1. Top block—energy supply 8.16. The top block of an energy balance—energy supply—is intended to show flows representing energy entering the national territory for the first time, energy removed from the national territory and stock changes. The entering flows consist of the production of primary energy products and imports of both primary and secondary energy products. The flows removing energy from the national territory are exports of primary and secondary energy products and international bunkers. 8.17. The balance item of the flows described above and the changes in stock represent the amount of energy that is available in the national territory during the reference period. This aggregate is named total energy supply (TES) and calculated as follows: > Total energy supply = > Primary energy production > + Import of primary and secondary energy > − Export of primary and secondary energy > − International (aviation and marine) bunkers > − Stock changes 8.18. As a common convention, the figures shown in the published energy balances already carry the sign that would be allocated through the above formula. While this is obvious in the case of exports and bunkers (e.g., showing an export of "-1000 tons of coal"), care should be taken when reading the values for stock changes, as the balances show them with an opposite sign than that which is described in their definition (see para. 5.16). This results in stock builds being shown with a negative value, which could be misinterpreted as a stock draw. 8.19. Primary energy production. Primary energy production (as defined in para. 5.10) is the capture or extraction of fuels or energy from natural energy flows, the biosphere and natural reserves of fossil fuels within the national territory in a form suitable for use. Inert matter removed from the extracted fuels and quantities re-injected, flared or vented are not included. The production of primary products is usually an activity of the energy industries. However, some primary energy products can be generated by industries other than the energy industries as autoproduction, as well as by households. 8.20. Imports and exports of energy products. Imports and exports of energy products are defined in paras. 5.11 and 5.12. They cover both primary and secondary energy products. 8.21. International bunkers. International bunkers cover both marine and aviation bunkers and are defined in paras. 5.14–5.15. 8.22. Stock changes. Stocks and stock changes are defined in para. 5.16. It is desirable, in principle, to record changes in all stocks located in the national territory at a specific moment in time, but it is recognized that in practice countries often find it difficult to obtain satisfactory data on changes in stocks held by final energy users. This problem is particularly troublesome in the case of the numerous non-industrial final users, making it therefore very costly to cover them in regular stock surveys. As countries may adopt different conventions for the calculation of the change in energy stocks, it is recommended that necessary clarification be provided in country metadata. Countries are encouraged to collect comprehensive data on stock changes from large companies, private or public, as a minimum. 8.23. A stock change can be the result of a stock build or a stock draw. To ensure comparability of energy statistics with the accepted practice in other areas of economic statistics, stock changes are measured as closing stock minus opening stock. Thus, a positive value of stock change is a stock build and represents a reduction in the supply available for other uses, while a negative value is a stock draw and represents an addition to the supply for other uses. 8.24. For each product, the row "total energy supply" reflects the supply of energy embodied in that particular energy product. The total supply of energy in the national territory is shown under the column "total". ### 2. Middle block—transfers, transformation, own use and losses 8.25. The main purpose of the middle block of an energy balance is to show transfers, energy transformation, energy industries own use and losses. 8.26. Transfers, the first line of the middle block, is essentially a statistical device to move energy between columns to overcome practical classification and presentation issues resulting from changes in use or identity of an energy product. Transfers cover, for example, the reclassification of oil products (which is necessary when finished oil products are used as feedstock in refineries) and the reclassification of products that no longer meet their original specifications (see para. 5.17). 8.27. Transformation. Energy transformation describes the processes that convert an energy product into another energy product that, in general, is more suitable for specific uses (see paras. 5.18 and 5.68–5.74). 8.28. The transformation of energy is normally performed by energy industries. However, many economic units not part of energy industries produce energy products to satisfy their own needs and/or to sell to third parties. When this involves the transformation of energy products, it is recorded in the balances in the middle block. Examples include manufacturing plants producing their own secondary electricity or heat (autoproducers). Another example of an economic unit included in transformation is blast furnaces (ISIC Group: 241—Manufacture of basic iron and steel), because its by-product, blast furnace gas, can have different energy uses, making it worthwhile to account for as the output of the transformation of coke. 8.29. Number of rows describing transformation. Each row under transformation specifies the kind of plant performing the energy transformation. A reference list of transformation plants and, therefore, rows to be reflected in the transformation part of the balance is provided in para 5.70. It is recommended that countries show in their balances, to the extent possible and applicable, energy transformation by the categories of plants, as presented in para 5.70. 8.30. Recording of inputs and outputs. It is recommended that: (a) energy entering transformation processes (e.g., fuels into electricity generation and heat generation, crude oil into oil refineries for the production of oil products, or coal into coke ovens for the production of coke and coke oven gas) be shown with a negative sign to represent the input, and (b) energy that is an output of transformation activities be shown as a positive number. The sum of the cells in each row appearing in the column "total" should therefore be negative as transformation always results in a certain loss of energy when expressed in energy units. A positive figure would suggest a gain of energy and, as such, would be an indication of incorrect data or metadata such as conversion factors. 8.31. Energy industries own use is defined as the consumption of fuels, electricity and heat for the direct support of the production and preparation for use of fuels and energy, except heat not sold (see para. 5.20). As such, it covers not only own use by the energy industries as defined in para. 5.23, but also by other energy producers as defined in para. 5.75. Typical examples are the consumption of electricity in power plants for lighting, compressors and cooling systems, or the fuels used to maintain the refinery process. A separate row in commodity and energy balances is used to show this consumption of energy for the purposes of energy production. For analytical purposes, the energy industries own use will often be further disaggregated by type of energy industry. 8.32. Losses. As defined in para. 5.19, losses are those that occur during the transmission, distribution and transport of fuels, electricity and heat. Losses also include venting and flaring of manufactured gases, losses of geothermal heat after production and pilferage of fuels or electricity (sometimes referred to as non-technical losses). ### 3. Bottom block—final consumption 8.33. The bottom block of an energy balance—final consumption—covers final energy consumption (i.e. flows reflecting energy consumption by energy consumers), as well as non-energy use of energy products. The final consumption is measured by the deliveries of energy products to all consumers. It excludes deliveries of fuel and other energy products for use in transformation processes and the use of energy products for the energy needs of the energy industries (both covered in the middle block). 8.34. As the energy balance involves application of the territory principle, final consumption covers all consumption in the national territory independent of the residence status of the consuming units. Thus, the energy consumption by residents abroad is excluded, while the energy consumed by non-residents (foreigners) within the national territory is included. 8.35. It is recommended that final energy consumption be grouped into three main categories: (i) manufacturing, construction and non-fuel mining industries, (ii) transport and (iii) other, and further disaggregated according to countries' needs (see chapter V for more detail). 8.36. Manufacturing, construction and non-fuel mining industries. The final consumption recorded under this category covers the use of energy products for energy purposes by economic units belonging to the industry groups listed below. It, however, excludes the use of energy products for transport, which is recorded under "transport" in a separate row. Taking into account the needs of energy policy makers and to ensure cross-country comparability of energy balances, it is recommended that countries show final energy consumption disaggregated according to the following groups (see table 5.3):[^65] - Iron and steel - Chemical and petrochemical - Non-ferrous metals - Non-metallic minerals - Transport equipment - Machinery - Mining and quarrying - Food and tobacco - Paper, pulp and print - Wood and wood products (other than pulp and paper) - Textile and leather - Construction - Industries not elsewhere specified 8.37. Transport. The purpose of this category is to provide information on the consumption of energy products by any economic entity in transporting goods and/or passenger between points of departure and destination within the national territory. As described in para. 5.89–5.96, transport should be disaggregated by mode of transport. 8.38. By convention, transport fuels used in fishing, farming and defence (including fuels for military means of transport) are not part of transport in the energy balance, because the main purpose of the fuel use in these activities is not for transport but rather for agriculture and defence. Similarly, energy used in lift trucks and construction machinery on industrial sites is considered as stationary consumption, not transport. The category "transport" is subdivided into the following modes of transport (see table 5.4): - Road - Rail - Domestic aviation - Domestic navigation - Pipeline transport - Transport not elsewhere specified 8.39. Energy used at compressor and/or pumping stations in pipeline transport (fuels and electricity) within the national territory is included in transport. However, it is recognized that some countries with a large production of oil and gas find it difficult to differentiate between energy for pipeline transport and other fuels consumed in the oil and gas extraction industries. 8.40. Other. This group consists of energy consumers not classified in the manufacturing, construction and non-fuel mining industries category. It is recommended that countries at least subdivide this group in the following way (see chapter V). - Households - Commerce and public services - Agriculture, forestry - Fishing - Not elsewhere specified (including defence activities) 8.41. As stated in para. 8.37 above, fuels used in tractors for the purpose of farming, in vessels for fishing and for transport by military vehicles are included here. Fuels and other energy products' consumption in fishing should cover all fishing vessels, including those engaged in deep-sea fishing. It is important to ensure that fuels and other energy products delivered to deep-sea fishing vessels are excluded from quantities reported as international marine bunkers. 8.42. It is recommended that countries further subdivide the major consumer groups identified above, reflecting their needs and the level of detail adopted in other areas of basic statistics. 8.43. Use of energy products for non-energy purposes. This use appears as a separate row in the energy balance. It can be further disaggregated by the compiling countries in accordance with their needs and priorities. For example, countries may wish to show non-energy use of energy products by the chemical and petrochemical industry, for transport[^66] and others. 8.44. The structure of the middle and bottom blocks of energy balances is designed to present various uses of energy products based on the concepts introduced in chapter V. Figure 8.1 below illustrates how the cross-classification of energy use by purpose and user groups described in chapter V and presented in figure 5.2 is reflected in energy balances. > **Figure 8.1 — Uses of energy and their presentation in an energy balance** > > Users \ Uses (matching the cross-classification of figure 5.2): Transformation (a); Energy industries own use (b) — not applicable to energy industries; Energy use excluding for transport (c) — not applicable to energy industries; Energy use for transport (d); Non-energy use (e). > > Energy industries (Electricity and heat, Coal Mines, Coke ovens, …) and Energy consumers (Iron and steel, …, Construction, …, Household, …) are the row users; the columns are the uses (a)–(e) as in figure 5.2. > > Correspondence to the energy balance (middle and bottom blocks): > - Transformation → box (a) > - Energy industries own use → box (b) > - Final consumption > - Final energy consumption > - Industry, total > - Transport > - Other, total: Households; Commercial and public services; Agriculture → boxes (c) and (d) > - Non-energy use → box (e) > > ### 4. Statistical difference 8.45. In the energy balance, the statistical difference is the numerical difference between the total supply of an energy product and the total use of it. It is presented in line 2 of the energy balance, as displayed in tables 8.1 and 8.2, and is calculated by subtracting the total use of energy (sum of lines 3 to 7) from the total supply of energy products (line 1). It arises from various practical limitations and problems related to the collection of the data that make up supply and demand. For example, the data may be subject to sampling or other collection errors, and/or be taken from different data sources that use different time periods, different spatial coverage, different fuel specifications or different conversions from volume to mass or from mass to energy content in the supply and demand sides of the balance. The reasons for a large statistical difference should be examined because this indicates that the input data are inaccurate and/or incomplete. 8.46. Statistical differences in commodity balances can provide an explanation for large statistical differences in an energy balance. For example, if the commodity balances show negligible statistical differences, this may indicate that the conversion factors to energy units should be investigated, as they may be the reason for the large statistical difference in the energy balance. Alternatively, if the statistical difference for a specific product's commodity balance is large, this may indicate that efforts should be made to investigate the data collection for that specific product. It is acknowledged that countries' experiences do vary with respect to the presentation and treatment of statistical differences. The forthcoming ESCM will provide an overview of the issues involved and identify good practices that countries might wish to follow. ## D. Templates of detailed and aggregated energy balances 8.47. As mentioned above, it is recommended that countries compile and disseminate an official annual energy balance every year. It is further recommended that countries follow as much as possible the template of a detailed energy balance as presented in table 8.1 below. **Table 8.1 — Template of a detailed energy balance** | Item code | Flows | E1 | E2 | E3 | … | Total | of which: Renewables | | --- | --- | --- | --- | --- | --- | --- | --- | | 1.1 | Primary production | | | | | | | | 1.2 | Imports | | | | | | | | 1.3 | Exports | | | | | | | | 1.4.1 | International marine bunkers | | | | | | | | 1.4.2 | International aviation bunkers | | | | | | | | 1.5 | Stock changes (closing-opening stocks) | | | | | | | | 1 | Total energy supply | | | | | | | | 2 | Statistical difference | | | | | | | | 3 | Transfers | | | | | | | | 4 | Transformation processes | | | | | | | | 4.1 | Electricity plants | | | | | | | | 4.2 | CHP plants | | | | | | | | 4.3 | Heat plants | | | | | | | | 4.3 | Coke ovens | | | | | | | | 4.4 | Patent fuel plants | | | | | | | | 4.5 | Brown coal briquette plants | | | | | | | | 4.6 | Coal liquefaction plants | | | | | | | | 4.7 | Gas works (and other conversion to gases) | | | | | | | | 4.8 | Blast furnaces | | | | | | | | 4.9 | Peat briquette plants | | | | | | | | 4.10 | Natural gas blending plants | | | | | | | | 4.11 | Gas-to-liquids (GTL) plants | | | | | | | | 4.12 | Oil refineries | | | | | | | | 4.13 | Petrochemical plants | | | | | | | | 4.14 | Charcoal plants | | | | | | | | 4.15 | Other transformation processes | | | | | | | | 5 | Energy industries own use | | | | | | | | 6 | Losses | | | | | | | | 7 | Final consumption | | | | | | | | 7.1 | Final energy consumption | | | | | | | | 7.1.1 | Manufacturing, const. and non-fuel mining industries, total | | | | | | | | 7.1.1.1 | Iron and steel | | | | | | | | 7.1.1.2 | Chemical and petrochemical | | | | | | | | 7.1.1.3 | Non-ferrous metals | | | | | | | | 7.1.1.4 | Non-metallic minerals | | | | | | | | 7.1.1.5 | Transport equipment | | | | | | | | 7.1.1.6 | Machinery | | | | | | | | 7.1.1.7 | Mining and quarrying | | | | | | | | 7.1.1.8 | Food and tobacco | | | | | | | | 7.1.1.9 | Paper, pulp and print | | | | | | | | 7.1.1.10 | Wood and wood products (other than pulp and paper) | | | | | | | | 7.1.1.11 | Textile and leather | | | | | | | | 7.1.1.12 | Construction | | | | | | | | 7.1.1.13 | Industries not elsewhere specified | | | | | | | | 7.1.2 | Transport, total | | | | | | | | 7.1.2.1 | Road | | | | | | | | 7.1.2.2 | Rail | | | | | | | | 7.1.2.3 | Domestic aviation | | | | | | | **Table 8.1 — Template of a detailed energy balance (continued)** | Item code | Flows | E1 | E2 | E3 | … | Total | of which: Renewables | | --- | --- | --- | --- | --- | --- | --- | --- | | 7.1.2.4 | Domestic navigation | | | | | | | | 7.1.2.5 | Pipeline transport | | | | | | | | 7.1.2.6 | Transport not elsewhere specified | | | | | | | | 7.1.3 | Other, total | | | | | | | | 7.1.3.1 | Agriculture and forestry | | | | | | | | 7.1.3.2 | Fishing | | | | | | | | 7.1.3.3 | Commerce and public services | | | | | | | | 7.1.3.4 | Households | | | | | | | | 7.1.3.5 | Not elsewhere specified | | | | | | | | 7.2 | Non-energy use | | | | | | | 8.48. It is recognized that countries may compile balances using a different format/structure. In some cases, an aggregated format may be sufficient and countries may adopt the aggregations that best suit their national purposes. However, to ensure international comparability and assist in monitoring implementation of various international agreements and conventions, it is recommended that the template presented in table 8.2 be used, as applicable, when only main aggregates have to be shown. **Table 8.2 — Template of an aggregated energy balance** | Item code | Flows | E1 | E2 | E3 | … | Total | of which: Renewables | | --- | --- | --- | --- | --- | --- | --- | --- | | 1.1 | Primary production | | | | | | | | 1.2 | Imports | | | | | | | | 1.3 | Exports | | | | | | | | 1.4 | International bunkers | | | | | | | | 1.5 | Stock change (closing-opening) | | | | | | | | 1 | Total energy supply | | | | | | | | 2 | Statistical difference | | | | | | | | 3 | Transfers | | | | | | | | 4 | Transformation processes | | | | | | | | 5 | Energy industries own use | | | | | | | | 6 | Losses | | | | | | | | 7 | Final consumption | | | | | | | | 7.1 | Final energy consumption | | | | | | | | 7.1.1 | Manufacturing, const. and non-fuel mining industries, total | | | | | | | | 7.1.1.1 | Iron and steel | | | | | | | | 7.1.1.2 | Chemical and petrochemical | | | | | | | | 7.1.1.X | Other industries | | | | | | | | 7.1.2 | Transport, total | | | | | | | | 7.1.2.1 | Road | | | | | | | | 7.1.2.2 | Rail | | | | | | | | 7.1.2.3 | Domestic aviation | | | | | | | | 7.1.2.4 | Domestic navigation | | | | | | | | 7.1.2.X | Other Transport | | | | | | | | 7.1.3 | Other, total | | | | | | | | 7.1.3.1 | of which: Agriculture, forestry and fishing | | | | | | | | 7.1.3.2 | of which: Households | | | | | | | | 7.2 | Non-energy use | | | | | | | 8.49. Additional information can be presented in supplementary tables and/or memorandum items to the energy balances. Examples of such information are: (i) flaring, venting and re-injection that might occur during the primary energy production, but are not covered in the balances (data item 3.3 "extraction losses" in chapter V); and (ii) flaring, venting and re-injection that occur during the transformation processes, and, even though covered in the energy balances, are not explicitly identified (included under "losses"). The collection and compilation of such information are very useful for a number of reasons, including their relevance for greenhouse gas emissions and, in the case of extraction losses, their links with the assessment of the depletion of underground deposits of the resource. In order to respond to specific user needs, supplementary information could be presented together with the energy balance. ## E. Data reconciliation and estimation of missing data 8.50. It is recognized that the compilation of an energy balance will require the use of various sources of data, including those collected by energy statisticians, as well as by compilers working in other statistical domains. This implies that the assessment of data accuracy, data reconciliation, estimation of missing data and imputation will play a significant role in processing the data during the compilation of the energy balance. While detailed information on good practices will be provided in the ESCM, some general recommendations can be formulated and are presented below. ### 1. Accuracy requirements 8.51. An energy balance includes interdependent elements of significantly differing levels of reliability, and it may become very difficult to assess the accuracy of the aggregated data. Such difficulties should not, however, be regarded as insurmountable barriers to progress but as challenges to be addressed as experience is gained and good practices are identified. It is recommended that accuracy requirements applicable to basic energy data used in the balance be clearly described in the energy statistics metadata of the country. ### 2. Estimation of missing data 8.52. It is recommended that countries estimate missing data in order to maintain the integrity of the balance and follow the imputation methods and general principles established in other areas of statistics,[^67] as well as good practices applicable to energy statistics, which will be elaborated in the forthcoming ESCM (see also chapter VII for a discussion of editing and imputation). ### 3. Reconciliation 8.53. As the compilation of energy balances requires use of data obtained from various data sources, reconciliation is needed to ensure the coherence of the data and the absence of double-counting. It is recommended that countries provide a summary of the performed reconciliation in the energy balance metadata to ensure the transparency of the energy balance preparation and to assist users in proper interpretation of the information contained therein and its relationship with other disseminated statistics. 8.54. Reconciliation of data on imports and exports of energy products and international bunkers. An example of data that need special attention are data on imports/exports of energy products and international bunkers. As official foreign merchandise trade statistics do not always satisfy the needs of balance compilers in this case, enterprise surveys might be needed to complement it in order to distinguish between these flows. However, it is recommended that the suitability of foreign merchandise trade statistics always be reviewed and available data used to the maximum extent possible to avoid duplication of efforts and publication of contradictory figures. If, however, the use of enterprise surveys becomes necessary, and differing figures on exports and imports of energy products are to be published in energy balances and trade statistics, an appropriate explanation of the differences should be published as part of the energy balance metadata. It is further recommended that energy and trade statisticians regularly review data collection procedures to ensure that the needs of energy statistics are met to the extent possible. A national correspondence table between the HS and SIEC should be developed and used to present external trade flows in the energy categories adopted for energy balance purposes. ## F. Commodity balances 8.55. Purpose. The purpose of a commodity balance is to show the sources of supply and the various uses of a particular energy product with reference to the national territory of the compiling country. The balance can be compiled for any energy commodity. Countries may use various formats of commodity balances depending on their needs and circumstances. However, it is recommended that the format of the energy balance and all applicable concepts defined in IRES consistently used in the compilation of a commodity balance to ensure data consistency. 8.56. The unit of measurement. The unit of measurement used in commodity balances is usually the original unit appropriate for the energy product in question (e.g., metric tons). However, a non-original energy unit (e.g., ton of oil equivalent or terajoule) can be used as well. 8.57. Format (template) of commodity balance. In general, a commodity balance can be compiled in a format similar to that of energy balances. However, not all flows (i.e. rows in the balance) may be applicable for all products. Common flows shown are:[^68] - Production (primary or secondary) - Production from other sources - Imports - Exports - International bunkers - Stock changes - Supply - Statistical difference - Transfers - Transformation input - Energy industries own use - Losses - Final consumption - Final energy consumption - Non-energy use 8.58. The most commonly used format for the presentation of energy commodity data is the commodity balance in which both the sources of supply and the uses for each commodity are shown in a single column. 8.59. It is recommended that commodity balances be constructed at the national level for every energy commodity in use, however minor, with certain commodities aggregated for working purposes. They should be considered as the basic framework for the compilation of national energy statistics and as a valuable accounting tool for constructing both energy balances and higher aggregates. A key indicator of the data quality of each product is the statistical difference row (see para. 8.45). 8.60. Differences in the flow layout of commodity balances as compared to an energy balance. Commodity balances provide details on the physical flows involving one energy product, and do not consider the interrelationships between different products. For this reason, it is logical to treat secondary production as "production" (in line with the concept of production in other areas of statistics) and not as the "output of transformation", while at the same time there is no need to show transformation inputs as a negative quantity. 8.61. While energy balances need to distinguish between fossil and non-fossil fuels, both to show what is renewable in total and to accurately calculate greenhouse gas inventories, for commodity balances, however, more interest lies in quantities consumed and the way they are. For example, commodity balances showing consumption of motor gasoline will include any quantities of blended biofuels, in contrast to energy balances. --- [^64]: It should be noted that the energy balance as presented in this chapter differs from the energy accounts of the SEEA-Energy, which are developed on the basis of concepts, definitions and classifications of the SNA (see chapter XI for details). [^65]: In addition, to ensure better harmonization of energy statistics with other economic statistics countries might also wish to compile energy consumption by applicable ISIC, Rev. 4 classes in their detailed energy balances. [^66]: In some balances, there is a separate item for transport. One example of non-energy use in transport is lubricants and greases used in engines. [^67]: See, for example, International Recommendation for Industrial Statistics (IRIS 2008). [^68]: For definitions and relationships between these terms refer to chapter VI.