Scope 4 CO2 emissions reflect the CO2 avoided by an activity. This 11-page note argues the metric warrants more attention. It yields an ‘all of the above’ approach to energy transition, shows where each investment dollar achieves most decarbonization and maximizes the impact of renewables.
Scope 1-3 CO2 emissions are now familiar to most decision-makers. Scope 1 captures the CO2 emitted directly in creating a product. Scope 2 adds the CO2 emitted in generating electricity used to create the product. And Scope 3 adds the CO2 emitted in using the product, for example, by combusting it. A summary is presented by fuel and by material on pages 2-3, with the implication that ‘everything is bad, only some things are less bad than others’.
Scope 4 CO2 is intended as an antidote to the depressed conclusion that ‘everything is bad’. It considers the CO2 avoided by an activity. Working from home avoids the CO2 of a commute. Building a wind farm may displace CO2-intensive coal. So too might developing a gas field. Thus the purpose of this note is to construct Scope 1-4 CO2 calculations for 20 different energy technologies, fairly, objectively, and then draw conclusions. The numbers are remarkable (page 4).
‘All of the above’. Every single option in our chart above has net negative Scope 1-4 CO2 emissions. The more investment that flows in to all of these categories, the faster the world will decarbonize. Our overall roadmap to net zero needs to treble global energy capex to over $3trn pa (pages 4-8).
Project developers and investors should consider Scope 4 CO2. Many categories with deeply negative Scope 1-4 CO2 emissions — sometimes achieving 3x more net CO2 abatement per $1bn of investment than wind, solar and EVs — have been unsuccessful in attractive capital. It may therefore be appealing for project-developers to present Scope 1-4 CO2 benefits on a clear and transparent basis. It may also be appealing for investors to communicate the Scope 1-4 CO2 of their portfolios to their own stakeholders (page 9).
Maximizing decarbonization. Scope 4 CO2 emissions depend on counterfactuals. What is an activity displacing? This matters across the board and can also promote faster decarbonization. For example, a new wind project that displaces nuclear achieves no net decarbonization, whereas an inter-connector that allows that same wind project to displace coal-power avoids 1.2 kg/kWh of CO2 (page 10).
Conceptual limitations of Scope 4 CO2 are discussed on page 11. However, we conclude it is an increasingly important metric for decision makers in the energy transition, to ensure adequate energy supplies are developed, while also decarbonizing as fast as possible.