4.1 Scenarios
Which scenarios should be used for setting science-based targets?
Context: The setting of a science-based target depends not only on the specific method used to set the
target but also on the scenarios used within the methodology. Historically, the SBTi recognized well-
below 2°C (WB2C), or targets with a likelihood of staying within ~1.7°C of warming, and 1.5°C targets
and required that these are met with low-overshoot, preferring scenarios that prioritize early action.
There are also important questions about the levels of carbon capture and storage (CCS), bioenergy
with carbon capture and storage (BECCS) and carbon dioxide removals (CDR) in scenarios meeting
the WB2C and 1.5°C goals. From 15 July 2022, the SBTi only accepts targets that are aligned with
1.5°C with no or limited overshoot. Overall, the higher the level of CCS the more lenient the transition
out of fossil fuels, and the higher the levels of BECCS and CDR are, the more dependent society is on
an even more uncertain technological fix to our current dependency on fossil energy. Scenarios with
high volumes of BECCS are also dependent on high volumes of bioenergy – some of which might not
be available unless other sustainability objectives are compromised.
Stance in draft guidance: The scenario proposed in the guidance includes early action and limited or
no overshoot. In addition, to avoid overreliance on bioenergy (linked to the use of BECCS), the draft
guidance proposes a potential physical limit on sustainable bioenergy (close to the range where there is
“high agreement”, <135 EJ/yr) in its scenario filtering. This results in only a few scenarios available for
the purpose of setting O&G SBTs.
Consultation response: When asked if any scenario that meets WB2C or 1.5C should be allowed,
over half of responses agreed that a criterion should be required to filter scenarios, with consideration
to levels of overshoot, need for early action and uncertain physical planetary limits. Over half of
respondents also agreed that an envelope of scenarios should be provided as opposed to just one but
that these should be filtered for implausibility. The primary concerns around the criteria to remove
implausible scenarios were largely centred around CCS, BECCS and CDR.
Post-consultation view: The SBTi’s immediate reflection on the consultation feedback was to
maintain the scenarios and criteria for inclusion set out in the draft guidance (limited or no overshoot,
early action and considerations to physical limits regarding bioenergy), but to reconsider the science to
set bioenergy limits.
Stance in corporate Net-Zero Standard: According to the SBTi Net=Zero Standard, scenarios for
reaching net-zero emissions at the global level by 2050 should assume only low/medium levels of CO
2
removal. The SBTi Pathways to Net-Zero provides further detail, stating that “no pathways currently
used by the SBTi include CO
2
removal with geologic storage in the pathway boundary”. The SBTi net-
zero pathways only consider CO
2
removal in the forestry, land and agricultural (FLAG) sectors and in
specific cases of bioenergy use. Based on the draft FLAG guidance, this includes only biogenic
removals, such as the restoration of natural ecosystems, improvements to forest management
practices, and enhanced soil carbon sequestration.