Data Items on Energy Flows and Stocks

This is part (ii) of Chapter VI’s reference list of data items (see part (i), unit characteristics). It relates to the collection of statistics, in physical units, on energy flows — production, transformation, consumption — and on stock levels of energy products, designed to produce consistent time series of supply and demand, support comparisons and analysis across products, and, once expressed in common units, feed the compilation of energy balances [IRES, Ch. VI, para. 6.38, PDF p. 91, 2018].

The data items are presented in two sub-categories: (i) data items common to all energy products, and (ii) data items applicable to a specific product group; both are required for the collection and dissemination of stock and flow statistics. Recommendations on units of measurement are given in Chapter IV [IRES, Ch. VI, para. 6.39, PDF p. 91, 2018].

Data items common to all energy products

For each product identified in SIEC, the following data items can be compiled as applicable [IRES, Ch. VI, para. 6.40, PDF p. 91, 2018]. Every row of this table is a data-item template over a flow already defined in Chapter V; the definitions below are not repeated here — follow the links.

Item number	Data item	Flow definition
1.1	Production	Production
1.2	Total imports	Imports and Exports
1.2.1	Imports by origin(a)	Imports and Exports
1.3	Total exports	Imports and Exports
1.3.1	Exports by destination(a)	Imports and Exports
1.4	International marine bunkers	International Bunkers
1.5	International aviation bunkers	International Bunkers
1.6	Stocks at the end of the period	Stock Changes
1.7	Stock changes	Stock Changes
1.8	Transfers	Stock Changes
1.9	Transformation (by transformation processes)(b)	Transformation
1.10	Losses	Losses
1.11	Energy use(c)	Energy Industries Own Use / Final Consumption
1.11.1	of which: for transport (by type of transport)(d)	Transport
1.12	Non-energy use	Non-Energy Use

Notes to table:

• (a) Acquiring precise information on the origin of imports and destination of exports is not always easy.
• (b) The transformation processes are described in Chapter V.
• (c) Depending on the statistical unit, energy use (excluding transport) corresponds to energy industries own use if the statistical unit is an energy industry (table 5.1) — or final energy consumption if the unit is an energy consumer (table 5.3).
• (d) The breakdown of transport is provided in table 5.4 — see Transport.

[IRES, Ch. VI, para. 6.40, Table, PDF pp. 91–92, 2018]

Data items applicable to a specific group of energy products

Coal and peat (SIEC sections 0 and 1)

For products classified under SIEC section 0 (Coal) and section 1 (Peat), the following additional data items apply [IRES, Ch. VI, para. 6.41, PDF p. 92, 2018]:

Item number	Data item
2.1	Production
2.1.1	of which: underground
2.1.2	of which: surface
2.2	Production from other sources

Underground production (2.1.1) — production from underground mines, where coal is produced by tunnelling into the earth to the coal bed and mining it with equipment such as cutting machines and continuous, longwall or shortwall mining machines [IRES, Ch. VI, para. 6.42, PDF p. 92, 2018].

Surface production (2.1.2) — production from surface mines, i.e. from coal-producing mines where the earth above or around the coal (overburden) is removed to expose the coal bed, then mined with surface excavation equipment (draglines, power shovels, bulldozers, loaders, augers); also known as area, contour, open-pit, strip or auger mines [IRES, Ch. VI, para. 6.43, PDF p. 92, 2018].

Production from other sources (2.2) — has two components: (a) recovered slurries, middlings and other low-grade coal products that cannot be classified by type of coal, including coal recovered from waste piles and other waste receptacles; and (b) fuels whose production is covered under other SIEC sections, e.g. from oil products (petroleum coke added to coking coal for coke ovens), natural gas (added to gas works gas for direct final consumption), biofuel and waste (industrial waste as a binding agent in patent-fuel manufacture) [IRES, Ch. VI, para. 6.44, PDF p. 92, 2018].

Natural gas (SIEC section 3)

For products classified under SIEC section 3 (Natural Gas), the following additional data items apply [IRES, Ch. VI, para. 6.45, PDF p. 92, 2018]:

Item number	Data item
3.1	Production
3.1.1	of which: associated gas
3.1.2	of which: non-associated gas
3.1.3	of which: colliery and coal seam gas
3.2	Production from other sources
3.3	Extraction losses(a)
3.3.1	of which: gas flared
3.3.2	of which: gas vented
3.3.3	of which: gas re-injected
3.4	Gas flared (except during extraction)
3.5	Gas vented (except during extraction)

Note to table: (a) losses occurring during the extraction of natural gas, not included under natural gas production; see para. 5.10 for the definition of production [IRES, Ch. VI, para. 6.45, Table, note (a), PDF p. 92, 2018].

Production (3.1) refers to dry marketable production within national boundaries, including offshore production, measured after purification and extraction of natural gas liquids (NGL) and sulphur; extraction losses and reinjected/vented/flared quantities are excluded, but quantities used within the natural gas industry itself (extraction, pipeline systems, processing plants) are included [IRES, Ch. VI, para. 6.46, PDF pp. 92–93, 2018]. Production is disaggregated into associated gas, non-associated gas, and colliery and coal seam gas — see the Natural Gas product page for the full product-classification treatment of these three categories [IRES, Ch. VI, para. 6.46, PDF p. 93, 2018]. Production from other sources (3.2) refers to gas produced from energy products already accounted for in the production of other energy products, e.g. blending petroleum gases, manufactured gases or biogases with natural gas [IRES, Ch. VI, para. 6.47, PDF p. 93, 2018].

Extraction losses (3.3) are losses occurring during extraction, not included in natural gas production:

• Gas flared — natural gas disposed of by burning in flares, usually at production sites or gas processing plants.
• Gas vented — natural gas released into the air at the production site or processing plants.
• Gas reinjected — reinjection of natural gas into an oil reservoir to increase oil recovery.

[IRES, Ch. VI, para. 6.48, PDF p. 93, 2018]

Flaring and venting can also occur after production — for example during the manufacture and transformation of certain gases — in which case they are reported separately under data items 3.4/3.5, and are implicitly included within the general losses data item (1.10 in the common-items table) rather than under extraction losses (3.3) [IRES, Ch. VI, para. 6.49, PDF p. 93, 2018].

Oil (SIEC section 4)

For products classified under SIEC section 4 (Oil), the following additional data items apply [IRES, Ch. VI, para. 6.50, PDF p. 93, 2018]:

Item number	Data item
4.1	Backflows from petrochemical industry to refineries
4.2	Refinery intake (by products)
4.3	Refinery losses
4.4	Direct use (of crude oil, NGL, etc.)

Backflows from petrochemical industry to refineries (4.1) — finished or semi-finished products returned from energy consumers to refineries for processing, blending or sale, usually by-products of petrochemical manufacturing; for integrated petrochemical industries this flow should be estimated. Transfers from one refinery to another within the country are not covered by this data item [IRES, Ch. VI, para. 6.51, PDF p. 93, 2018].

Refinery intake (4.2) — the amount of oil (including other hydrocarbons and additives) that has entered the refinery process [IRES, Ch. VI, para. 6.52, PDF p. 93, 2018].

Refinery losses (4.3) — losses during the refinery processes, the difference between refinery intake (observed) and production from refineries (gross refinery output); may occur, for example, during distillation due to evaporation. Reported as a positive number in a mass balance — although there may be volumetric gains, there are no gains in mass [IRES, Ch. VI, para. 6.53, PDF p. 93, 2018].

Direct use (4.4) — use of crude oil, NGL and other hydrocarbons directly, without being processed in oil refineries, e.g. crude oil burned for electricity generation [IRES, Ch. VI, para. 6.54, PDF p. 93, 2018].

Electricity and heat (SIEC sections 7 and 8)

For products classified under SIEC section 7 (Electricity) and section 8 (Heat), the following additional data items apply [IRES, Ch. VI, para. 6.55, PDF p. 94, 2018]:

Item number	Data item
5.1	Gross production (by type of producer, by type of plant and by production process)(a)
5.2	Own use
5.3	Net production (by type of producer, by type of plant and by production process)(a)
5.4	Use of energy products (by energy products and by transformation processes)

Note to table: (a) see Section D.1 of Chapter V for the list of producer types, plant types and production processes [IRES, Ch. VI, para. 6.55, Table, note (a), PDF p. 94, 2018].

Gross electricity production (5.1) — the sum of electrical energy production by all generating units/installations concerned (including pumped storage), measured at the output terminals of the generators [IRES, Ch. VI, para. 6.56, PDF p. 94, 2018]. Gross heat production — the total heat produced by the installation, including heat used by the installation’s auxiliaries that use a hot fluid (e.g. liquid fuel heating) and losses in installation/network heat exchanges, plus heat from chemical processes used as a primary energy form. For autoproducers, gross heat production covers only heat sold to third parties, so gross heat production for autoproducers equals net heat production [IRES, Ch. VI, para. 6.57, PDF p. 94, 2018].

Net electricity production (5.3) — gross electricity production less the electrical energy absorbed by the generating auxiliaries and the losses in the main generator transformers [IRES, Ch. VI, para. 6.58, PDF p. 94, 2018]. Net heat production — the heat supplied to the distribution system, as determined from measurements of the outgoing and return flows [IRES, Ch. VI, para. 6.59, PDF p. 94, 2018].

Own use (5.2) is defined, for this data item, simply as the difference between gross and net production [IRES, Ch. VI, para. 6.60, PDF p. 94, 2018]. This computed “own use” data item is distinct from the energy industries own use (EIOU) flow concept of Chapter V: EIOU is a flow category covering an energy industry’s or other energy producer’s own consumption of energy in support of energy production, transformation and distribution activities [IRES, Ch. V, para. 5.20, PDF p. 71, 2018], whereas the “own use” data item here (5.2) is simply the generation/transmission-loss gap between the gross- and net-production measurements at a single plant — a narrower, purely computational quantity, not a claim about which flow category the underlying energy consumption is reported under.

Use of energy products (5.4) — the quantity of energy products used for the generation of electricity and heat, by energy product and by transformation process [IRES, Ch. VI, para. 6.61, PDF p. 94, 2018].

Related

• IRES Chapter VI — Statistical Units and Data Items — the chapter digest this page supports
• Production, Imports and Exports, International Bunkers, Stock Changes, Transformation, Losses, Final Consumption, Non-Energy Use, Energy Industries Own Use — the nine flow pages this page’s common data-item table templates over
• SIEC Classification System — the product classification the product-specific sub-tables are organized by section
• Transport — the transport-mode breakdown for data item 1.11.1
• Coal, Peat and Peat Products, Natural Gas, Oil, Electricity, Heat — the SIEC product sections these product-specific data items apply to
• Commodity Balance — the single-product balance these flow and stock data items are compiled into, one column per commodity (IRES Ch. VIII, paras 8.55–8.59)