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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


This year’s Statistical Review introduces two changes in how oil and gas are reported in energy units. First, primary consumption of energy from oil is now reported in tonnes of oil equivalent where one tonne of oil is defined as 10 Gcal (gigacalories) or 41.868 GJ (gigajoules). Second, the tables now report natural gas volumes in terms of a standardized gas at a temperature of 15˚C and a pressure of 1013 mbar with a gross calorific value of 40 MJ (megajoules) per cubic metre.

 

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.

 

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

 

The primary energy values of nuclear and hydroelectric power generation, as well as electricity from renewable sources, have been derived by calculating the equivalent amount of fossil fuel required to generate the same volume of electricity in a thermal power station, assuming a conversion efficiency of 38% (the average for OECD thermal power generation).

 

The Other renewables table shows consumption of commercial electricity produced from renewable sources. Electricity from renewable sources is converted to tonnes of oil equivalent following the same methodology used for nuclear and hydroelectricity and is included in the primary energy consumption calculation.

 

Biofuels consumption continues to be included in oil consumption data (see footnotes to oil consumption table).

More detail on the methodology

Primary energy

In this review, primary energy comprises commercially traded fuels, including modern renewables used to generate electricity.

 

Oil

 

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.

 

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.

 

Although every effort is made to come up with a consistent series for reserves based on a common definition, in reality different countries use different methodologies and the data have varying levels of reliability. Caution therefore needs to be exercised in attempting precise comparisons between nations or analyses of time 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. R/P ratios for the region and the world are depicted in the chart above and the Energy charting tool and World Energy app.

 

In the absence of replenishment by successful exploration or reserves growth, so-called 'reserves replacement', proved reserves would tend to decline over time as production depleted the existing reserve base. However, the tendency has been for proved reserves at the aggregate level to increase over time as reported discoveries, extensions and improved recovery have exceeded production.

 

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.

 

Oil production

Oil production data includes crude oil, tight oil, oil sands and NGLs (the liquid content of natural gas where this is recovered separately). The data excludes liquid fuels from other sources such as biomass and derivatives of coal and natural gas. 

 

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

 

Oil and oil product consumption

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.

 

Data are supplied in both volume and weight measures. An extended breakdown of oil consumption by product group e.g. gasoline, diesel/gasoil, jet/kerosene is available in the Excel workbook.

 

Regional consumption of oil products classified in thousand barrels per day as: light distillates, middle distillates, fuel oil and others.

 

Light distillates

 

Light distillates consist of aviation and motor gasolines and light distillate feedstock (LDF).

 

Middle distillates

 

Middle distillates consist of jet, heating kerosenes, gas and diesel oils (including marine bunkers).

 

Fuel oil

 

Fuel oil includes marine bunkers and crude oil used directly as fuel.

 

Others

 

Others consist of refinery gas, liquefied petroleum gas (LPG), solvents, petroleum coke, lubricants, bitumen, wax, other refined products and refinery fuel and loss.

 

Oil 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 data and map illustrate the flow of crude oil and products between sources of production and the regions of consumption.

 

The tables exclude the intra-area movements of oil (for example, crude oil and products moving between countries within Europe). Bunkers are 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 also shown. Data in the tables are in million tonnes and thousand barrels per day.

 

Natural gas

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.

 

Reserves-to-production (R/P) ratios are available by country and feature in the table of gas reserves. R/P ratios for the region and the world are depicted in the chart above the Energy charting tool and World Energy app.

 

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.

 

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.

 

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 million tonnes oil equivalent (mtoe). 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.

 

Consumption data in the PDF data table is in billion cubic meters (bcm) and million tonnes oil equivalent (mtoe), 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. Natural gas trade is shown in billion cubic metres (bcm).

 

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.

 

Coal production

Coal production includes data for commercial 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 data excludes coal converted to liquid or gaseous fuels but includes coal consumed in transformation processes.

 

In the coal production PDF table, the units are in million tonnes oil equivalent (mtoe). 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.

 

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).

 

Nuclear energy

Data are based on gross generation and not accounting for cross-border electricity supply.

 

The primary energy value of nuclear power generation has been derived by calculating the equivalent amount of fossil fuel required to generate the same volume of electricity in a thermal power station, assuming a conversion efficiency of 38% (the average for OECD thermal power generation).

 

Data for the units are in million tonnes oil equivalent (mtoe) in the PDF. In addition the data are available in the Excel workbook in terawatt–hours (Twh).

 

Hydroelectricity

Data are based on gross primary hydroelectric generation and not accounting for cross-border electricity supply. The primary energy value of hydroelectricity generation has been derived by calculating the equivalent amount of fossil fuel required to generate the same volume of electricity in a thermal power station, assuming a conversion efficiency of 38% (the average for OECD thermal power generation).

 

In the hydroelectricity consumption PDF table, the units are in million tonnes oil equivalent (mtoe). In addition the data are available in the Excel workbook in terawatt-hours (Twh).