Proved reserves and proved undeveloped reserves

Proved reserves

The proved oil and gas reserves of Shell subsidiaries and the Shell share of the proved oil and gas reserves of joint ventures and associates are set out in more detail in “Supplementary Information – Oil and Gas (unaudited)”.

Before taking production into account, our proved reserves increased by 1,470 million boe in 2021. This consisted of an increase of 1,322 million boe from Shell subsidiaries and an increase of 148 million boe from the Shell share of joint ventures and associates.

After taking production into account, our proved reserves increased by 241 million boe in 2021 to 9,365 million boe at December 31, 2021.

Shell subsidiaries

Before taking production into account, Shell subsidiaries’ proved reserves increased by 1,322 million boe in 2021. This consisted of an increase of 637 million barrels of crude oil and natural gas liquids, an increase of 775 million boe (4,494 thousand million scf) of natural gas and a decrease of 90 million barrels of synthetic crude oil. The 1,322 million boe increase was the result of a net increase of 1,091 million boe from revisions and reclassifications, an increase of 430 million boe from extensions and discoveries, an increase of 31 million boe from improved recovery, and a net decrease of 230 million boe related to purchases and sales of minerals in place.

After taking into account production of 1,088 million boe (of which 41 million boe were consumed in operations), Shell subsidiaries’ proved reserves increased by 234 million boe in 2021 to 8,456 million boe. In 2021, Shell subsidiaries’ proved developed reserves (PD) decreased by 238 million boe to 6,740 million boe, and proved undeveloped reserves (PUD) increased by 472 million boe to 1,716 million boe.

Shell share of joint ventures and associates

Before taking production into account, the Shell share of joint ventures and associates’ proved reserves increased by 148 million boe in 2021. This consisted of an increase of 48 million barrels of crude oil and natural gas liquids and an increase of 100 million boe (580 thousand million scf) of natural gas. The 148 million boe increase comprised a net increase of 146 million boe from revisions and reclassifications and an increase of 2 million boe from extensions and discoveries.

After taking into account production of 141 million boe (of which 7 million boe were consumed in operations), the Shell share of joint ventures and associates’ proved reserves increased by 7 million boe to 909 million boe at December 31, 2021.

The Shell share of joint ventures and associates’ PD increased by 8 million boe to 801 million boe, and PUD decreased by 3 million boe to 108 million boe.

For further information, see “Supplementary Information – oil and gas (unaudited)”.

Proved undeveloped reserves

In 2021, Shell subsidiaries and the Shell share of joint ventures and associates’ PUD increased by 469 million boe to 1,824 million boe. There were decreases of 467 million boe because of maturation to PD, mainly 129 million boe in Troll (Norway), 69 million boe in Tupi (Brazil), and 269 million boe spread across other fields, and a net decrease of 26 million boe due to purchases and sales. These were offset by: increases of 498 million boe due to revisions, an increase of 31 million boe due to improved recovery, and a net increase of 432 million boe due to extensions and discoveries. The extensions and discoveries consisted of 107 million boe in Mero, 81 million boe in Whale, and 244 million boe spread across other fields.

In addition to the maturation of 467 million boe from PUD to PD, 51 million boe was matured to PD from contingent resources through PUD as a result of project execution during the year.

PUD held for five years or more (PUD5+) at December 31, 2021, amounted to 238 million boe, an increase of 54 million boe compared with the end of 2020, which was driven mainly by changes in Kolo Creek (Nigeria), Tupi (Brazil) and Groundbirch (Canada).

The fields with the largest PUD5+ on December 31, 2021 were Lunskoye (Russia), Gorgon (Australia), Kolo Creek (Nigeria) and Tupi (Brazil).

These PUD5+ remain undeveloped because development either requires the installation of compression equipment (Russia) and the drilling of additional wells (Brazil) or will take longer than five years because of the complexity and scale of the project (Australia).

During 2021, we spent $5.3 billion on development activities related to PUD maturation.