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  5. Methodology

Methodology

The Statistical Review provides a globally consistent data time series.  Here we outline the definitions, conversion factors and calculations we use to produce the report

More detail on the methodology

Primary energy

Traditionally, in bp’s Statistical Review of World Energy, the primary energy of non-fossil based electricity (nuclear, hydro, wind, solar, geothermal, biomass in power and other renewables sources) has been calculated on an ‘input-equivalent’ basis – i.e. based on the equivalent amount of fossil fuel input required to generate that amount of electricity in a standard thermal power plant. For example, if nuclear power output for a country was 100 TWh, and the efficiency of a standard thermal power plant was 38%, the input-equivalent primary energy would be 100/0.38 = 263 TWh or about 0.95 EJ.


For many years, the efficiency of this standard power plant has been assumed to be 38%. However, in reality, the world average efficiency of fossil fuel-based power changes over time and has risen from around 36% in 2000 to over 40% today. Moreover, given the much higher efficiency of the most modern power plant (e.g. the thermal efficiency of a modern gas turbine plant is above 55%), the global average is expected to increase in the future.


Therefore, to better assess primary energy trends, we have decided to move to a time-dependent thermal equivalence model. The conversion factor used each year to calculate the ‘input-equivalent’ consumption for a given level of generation is based on a simplified representation of measured average efficiency levels:

 

  • 1965-2000: assumed constant efficiency of 36%
  • 2000-2017: a linear increase from 36% to 40% based on observed data
  • 2018 onwards: the annual rate of efficiency improvement is based on the simplified assumption that efficiency will increase linearly to 45% by 2050.


The table below quantifies these assumptions (rounded to 1 decimal place):

Thermal equivalent efficiency factors used to convert non-fossil electricity (excluding biomass-powered electricity) to primary energy
 Year  Efficiency factor (%)    Year  Efficiency factor (%)
 1965-2000  36.0   2011  38.6
 2001  36.2    2012  38.8
 2002  36.5    2013  39.1
 2003  36.7    2014  39.3
 2004  36.9    2015  39.5
 2005  37.2    2016  39.8
 2006  37.4    2017  40.0
 2007  37.6    2018  40.2
 2008  37.9    2019  40.4
 2009  38.1    2020  40.5
2010  38.4    2021  40.6

In this year’s Statistical Review, we have also updated the thermal equivalent efficiency factor used to convert electricity generation from biomass to primary energy equivalent. In the previous editions, we used the same factor for biomass as for all non-fossil electricity. In this edition, we assume a constant efficiency of 32% for biomass power to better reflect the actual efficiency of biomass power plants.


Primary energy consumption is reported in net terms. The gross calorific value to net calorific value adjustment is fuel-specific.


Fuels used as inputs for conversion technologies (gas-to-liquids, coal-to-liquids and coal-to-gas) are counted as production for the source fuel and the outputs are counted as consumption for the converted fuel.

 

Oil

Reserves

Total proved reserves of oil are generally taken to be those quantities that geological and engineering information indicates with reasonable certainty can be recovered in the future from known reservoirs under existing economic and geological conditions.


The data series for proved oil reserves in this year’s review does not necessarily meet the definitions, guidelines and practices used for determining proved reserves at company level, for instance as published by the US Securities and Exchange Commission nor does it necessarily represent bp's view of proved reserves by country. Rather the data series has been compiled using a combination of primary official sources and third-party data.


 Oil reserves include field condensate and natural gas liquids as well as crude oil. This inclusive approach helps to develop consistency with the oil production numbers published in the Review, which also include these categories of oil. The reserves and R/P ratio for Canada includes Canadian oil sands and the reserves and R/P ratio for Venezuela includes the Orinoco Belt.


Liquid hydrocarbon fuels from non-hydrocarbon sources, such as ethanol from corn or sugar or synthetic oil derived from natural gas (so-called GTL or gas-to-liquids), are not included in either the reserves or production series.


We have provided a detailed explanatory note on reserves clarifying current definitions and terminology.


R/P ratios represent the length of time that those remaining reserves would last if production were to continue at the previous year's rate. They are calculated by dividing remaining reserves at the end of the year by the production in that year.


Reserves-to-production (R/P) ratios are available by country and feature in the table of oil reserves. There is a time series of crude oil reserves from 1980, which can be found in the Excel workbook. Data are measured in thousand million barrels.


Please note that due to process improvements for the Statistical Review that these reserves tables have not been updated this year.

 

Production

Oil production data includes crude oil, shale oil, oil sands, condensates (lease condensate or gas condensates that require further refining) and NGLs (natural gas liquids – ethane, LPG and naphtha separated from the production of natural gas). Excludes liquid fuels from other sources such as biofuels and synthetic derivatives of coal and natural gas. This also excludes liquid fuel adjustment factors such as refinery processing gain. Excludes oil shales/kerogen extracted in solid form.


The split of crude/condensate and natural gas liquids figures are available. The crude condensate table includes crude oil, shale/tight oil, oil sands, lease condensate or gas condensates that require further refining. Excludes liquid fuels from other sources such as biomass and synthetic derivatives of coal and natural gas. The NGL’s table includes ethane, LPG and naphtha separated from the production of natural gas. Excludes condensates.


World oil production tables are available in both thousand barrels daily and million tonnes.

 

Liquids, oil and oil product consumption 

Oil consumption as defined in previous Statistical Reviews (i.e. including biofuels) has been renamed ‘liquids’ consumption and a table is still included on this original basis. In addition, more granularity has been included on the product split of both oil products and biofuels (breaking out ethane & LPG and naphtha in oil products and the ethanol/biodiesel split of biofuels).


Total liquids consumption comprises inland demand plus international aviation and marine bunkers and refinery fuel and loss. Consumption of biogasoline (such as ethanol), biodiesel and derivatives of coal and natural gas are also included.


Oil consumption figures include inland demand plus international aviation and marine bunkers and refinery fuel and loss. Consumption of biogasoline (such as ethanol), biodiesel and derivatives of coal and natural gas are excluded. Derivatives of coal and natural gas are included.


Oil product consumption – Gasoline includes motor and aviation gasoline, gasolines and light distillate feedstock (LDF). Diesel/gasoil includes marine gasoil. ‘Fuel oil’ includes marine bunkers and crude oil used directly for fuel. ‘Others’ consists of refinery gas, solvents, petroleum coke, lubricants, bitumen, wax, other refined products and refinery fuel and loss. 


Data are supplied in both exajoules and thousand barrels daily figures.

 

Prices

The key crudes quoted are Brent, West Texas Intermediate (WTI), Nigerian Focados and Dubai in US$ per barrel.


The spot crude price history from 1972 and annual crude price history from 1861 are available in the historical data excel workbook.


Using S&P Global Platts data


The redistribution or reproduction of data whose source is S&P Global Platts is strictly prohibited without prior authorization from S&P Global Platts.

 

Email: support@platts.com

 

Refining

The refinery capacity data presented in this Review represents the sum of reported atmospheric crude distillation and condensate splitting capacity. Capacity should comprise the amount of input that a distillation facility can process under usual operating conditions, taking into account scheduled downtime. Figures are in thousand barrels daily at year end per calendar day.


Refinery throughputs are based on the quantity of crude and condensate processed in atmospheric distillation units and condensate splitters. Figures are in thousands of barrels per day.


The refining margins presented are benchmark margins for three major global refining centres: US Gulf Coast (USGC), North West Europe (NWE – Rotterdam) and Singapore. In each case they are based on a single crude oil appropriate for that region and have optimized product yields based on a generic refinery configuration (cracking, hydrocracking or coking), again appropriate for that region. The margins are on a semi-variable basis, i.e. the margin after all variable costs and fixed energy costs.

 

Oil trade movements

The tables exclude the intra-area movements of oil (for example, crude oil and products moving between countries within Europe). They do not include biofuels. Bunkers fuel is not included as exports. Crude imports and exports include condensates. Saudi Arabian exports from 1980 are also available in the oil trade movements table in the Excel workbook. The split of crude oil and products are detailed. Data in the tables are in million tonnes and thousand barrels per day.

 

Natural gas

Reserves

Total proved reserves of natural gas are generally taken to be those quantities that geological and engineering information indicates with reasonable certainty can be recovered in the future from known reservoirs under existing economic and operating conditions.


The data series for proved natural gas reserves in this year’s Review does not necessarily meet the definitions, guidelines and practices used for determining proved reserves at company level, for instance as published by the US Securities and Exchange Commission nor does it necessarily represent bp's view of proved reserves by country. Rather, the data series has been compiled using a combination of primary official sources and third-party data.


Although every effort is made to come up with a consistent series for reserves based on a common definition, different countries use different methodologies and the data have varying levels of reliability.


R/P ratios represent the length of time that those remaining reserves would last if production were to continue at the previous year's rate. They are calculated by dividing remaining reserves at the end of the year by the production in that year.


As far as possible, the data represents standard cubic metres (measured at 15°C and 1013 mbar) and have been standardized using a gross calorific value (GCV) of 40 MJ/m3.


There is a time series of natural gas reserves, which can be found in the Excel workbook. Data are measured in billion cubic metres.


Please note that due to process improvements for the Statistical Review that these reserves tables have not been updated this year.

 

Natural gas production

Gas production comprises marketed production and excludes gas flared or recycled gas. Includes natural gas produced for gas-to-liquids transformation.


As far as possible, the data above represents standard cubic metres (measured at 15°C and 1013 mbar); as they are derived directly from tonnes of oil equivalent using an average conversion factor and have been standardized using a gross calorific value (GCV) of 40 MJ/m3, they do not necessarily equate with gas volumes expressed in specific national terms.


Natural gas production is provided in three different units of measurement to accommodate regional customary usage. World natural gas production PDF tables are in both billion cubic metres, and exajoules. Data in the Excel workbook are also in billion cubic feet per day (bcf/d).

 

Natural gas consumption

Natural gas consumption excludes natural gas converted to liquid fuels but includes derivatives of coal as well as natural gas consumed in gas-to-liquids transformation.


As far as possible, the data above represents standard cubic metres (measured at 15°C and 1013 mbar); as they are derived directly from tonnes of oil equivalent using an average conversion factor and have been standardized using a gross calorific value (GCV) of 40 MJ/m3 they do not necessarily equate with gas volumes expressed in specific national terms. The difference between these world consumption figures and the world production statistics is due to variations in stocks at storage facilities and liquefaction plants, together with unavoidable disparities in the definition, measurement or conversion of gas supply and demand data.


Consumption data in the PDF data table is in billion cubic meters (bcm) and exajoules, data in billion cubic feet per day (bcf/day) can be found in the Excel workbook.

 

Natural gas prices

Annual prices are given for benchmark natural gas hubs together with contracted pipeline and LNG imports. The benchmark hub prices incorporate US (Henry Hub), Canada (Alberta), Netherlands TTF index and the UK (NBP). Contract prices are represented by LNG imports into Japan, the Japan Korea Marker (JKM) and Average German Import Prices.


The prices for LNG and European border are calculated as CIF prices, where CIF = cost + insurance + freight (average freight prices) in US dollars per million British thermal units (Btu).

 

Natural gas trade movements

Trade flows are on a contractual basis and may not correspond to physical gas flows in all cases. The data illustrates the flow of pipeline natural gas and LNG between sources of production and the regions of consumption. LNG trade. As far as possible, the data represents standard cubic metres (measured at 15ºC and 1013 mbar) and has been standardized using a gross calorific value (GCV) of 40 MJ/m3.

 

Coal

Coal reserves

Total proved reserves of coal are generally taken to be those quantities that geological and engineering information indicates with reasonable certainly can be recovered in the future from known deposits under existing economic and operating conditions.


Total proved coal reserves are shown for anthracite and bituminous (including brown coal) and sub-bituminous and lignite.


Reserves-to-production (R/P) ratios represent the length of time that those remaining reserves would last if production were to continue at the previous year's rate. They are calculated by dividing remaining reserves at the end of the year by the production in that year. The R/P ratios are calculated excluding other solid fuels in reserves and production.


R/P ratios are available by country and feature in the table of coal reserves. R/P ratios for the region and the world are depicted in the chart above and the Energy charting tool. Coal reserve data is in million tonnes.


Please note that due to process improvements for the Statistical Review that these reserves tables have not been updated this year.

 

Coal production

Coal production includes data for commercial solid fuels only. Included in the hard coal category are bituminous and anthracite (hard coal). The sub-bituminous coal includes lignite and brown coal. Other commercial solid fuels are also included. The data includes coal produced for coal-to-liquids and coal-to-gas transformations.


In the coal production PDF table, the units are in exajoules. The data can also be downloaded from the Excel workbook in million tonnes.

 

Coal consumption

Coal consumption includes data for solid fuels only. Included in the hard coal category are bituminous and anthracite. The sub-bituminous coal includes lignite and brown coal. Other commercial solid fuels are also included. The figures exclude coal converted to liquid or gaseous fuels, but includes coal consumed in transformation processes.


Differences between world consumption figures and the world production statistics are accounted for by stock changes, and unavoidable disparities in the definition, measurement or conversion of coal supply and demand data.

 

Coal prices

Annual prices quoted include the Northwest Europe marker price, Japan steam spot CIF price, China Quinhuangdao spot price and the US Central Appalachian coal spot price index. Coal prices except for the US Central Appalachian price are calculated as CIF prices, where CIF = cost + insurance + freight (average freight prices). The US Central Appalachian price is FOB = free on board. All prices are quoted in US dollars per tonne.


IHS Northwest Europe prices for 1996-2000 are the average of the monthly marker, 2001-2017 the average of weekly prices. IHS Japan prices basis = 6,000 kilocalories per kilogram NAR CIF. Chinese prices are the average monthly price for 2000-2005, weekly prices 2006-2017, 5,500 kilocalories per kilogram NAR, including cost and freight (CFR).

 

Coal trade movements

Commercial solid fuels only, i.e. bituminous coal and anthracite (hard coal), and lignite and brown (sub-bituminous) coal, and other commercial solid fuels. Intra-area movements (for example, between countries in Europe, Other CIS, Other Africa, Other Asia Pacific) are excluded.

Nuclear energy

The data are based on gross generation and not accounting for cross-border electricity supply. ’Input-equivalent’ energy is the amount of fuel that would be required by thermal power stations to generate the reported electricity output.

 

Details on thermal efficiency assumptions are available here.

 

Data for the units are in exajoules in the PDF. The data are available in the Excel workbook in terawatt–hours (TWh).

Hydroelectricity

The data are based on gross generation and not accounting for cross-border electricity supply. ‘Input-equivalent’ energy is the amount of fuel that would be required by thermal power stations to generate the reported electricity output. 

 

Details on thermal efficiency assumptions are available here.

In the hydroelectricity consumption PDF table, the units are in exajoules. The data are available in the Excel workbook in terawatt-hours (TWh).

Renewable energy

Renewables

The data are based on gross generation and not accounting for cross-border electricity supply. ‘Input-equivalent’ energy is the amount of fuel that would be required by thermal power stations to generate the reported electricity output.

 

Details on thermal efficiency assumptions are available here

Renewable power is based on gross generation from renewable sources including wind, geothermal, solar, biomass and waste, and not accounting for cross-border electricity supply.

 

Biofuels production and consumption

The data includes biogasoline (such as ethanol) and biodiesel. Volumes have been adjusted for energy content. 


The biofuels PDF tables are in thousand barrels of oil equivalent per day figures. The data are available in additional units in the Excel workbook.

Electricity
Electricity generation is based on gross output.
Carbon

Carbon emissions from primary energy use are estimated by applying the Default CO2 Emission ‎Factors for Combustion to the consumption of each energy product type (coal, natural gas and ‎various oil products) from the list of IPCC emission factors. Biofuels are considered as not emitting ‎CO2, consistent with the practice of the IEA. Second, the revised method takes account of fuel ‎consumption used for non-combustion purposes, such as the use of oil products and natural gas in ‎the petrochemicals industry or of oil to produce bitumen for road construction. Estimates of the ‎share of non-combusted fossil fuels taken from the IEA’s energy balances are subtracted from the ‎total consumption of fossil fuels before applying the relevant emission factors.


Carbon ‎emissions from flared natural gas are calculated using data series on volumes of gas flared from two sources: Cedigaz up to 2012, and the ‎Payne Institute for Public Policy, Colorado School of Mines, from 2013 onward. Payne Institute’s data ‎include flaring from upstream, downstream oil and gas, while Cedigaz include flaring from upstream ‎only. Volumes of gas flared have been standardised using a Gross Calorific Value (GCV) of 40 MJ/m3. ‎The IPCC Default CO2 Emission Factor for Combustion for natural gas (56,100 kg CO2 per TJ) is used ‎and perfect combustion has been assumed. These emissions represent around 1% of total CO2 ‎emissions.‎


Data for methane emissions associated with the production, transportation and distribution of fossil fuels for 1990-2020 are sourced, where available, from IEA (2021, 2022) Greenhouse Gas Emissions from Energy (all rights reserved). For a selected number of fossil fuel-producing countries where methane emission data is not currently available, an estimate of historical methane emissions has been derived using regional average methane intensity of production. For 2021, methane emission estimates are derived for all countries using methane intensity of fossil fuel production in 2020. Total methane emissions at a global and regional level show a discrepancy with IEA data due to non-inclusion of residual emissions i.e. emissions which have not been allocated to named countries. There is a wide range of uncertainty with respect to both current estimates of methane emissions and the global warming potential of methane emissions. To ensure alignment with financial and government reporting standards, the methane to CO2e factor is a 100-year Global Warming Potential (GWP) of 25, recommended by the IPCC in AR4.


Carbon emissions from industrial processes refer only to non-energy CO2 emissions from cement production and are sourced for 1990-2021 from Andrew, R. M. (2019) Global CO2 emissions from cement production, 1928-2018. Earth System Science Data 11, 1675-1710, (updated dataset May 2022).

 

Detail on the methodology, including estimating CO2 emissions, is available for download.