Electricity Maps provides full transparency on its data sources and methodology used to provide all signals.
A detailed methodology page with FAQs is available on the website.
Two whitepapers are also available on our website:
Guides and resources
Compliance with carbon accounting standards
GHG Protocol Scope 2 and 3 compliance
Electricity Maps direct emission factors correspond to GHG Protocol Scope 2 reporting. As necessary, reporting entities using Electricity Maps data for carbon accounting can isolate the exact delta between the life cycle and direct values to populate Scope 3 Category 3 (Fuel- and Energy-Related Activities) inventories natively, without introducing interpretive ambiguity or risking double-counting under Scope 2 boundaries.
ISO-14064 compliance
To ensure compliance with ISO 14064-1:2018 requirements, reporting entities can properly map Electricity Maps carbon intensity to their corresponding indirect greenhouse gas emission categories:
- Category 2: Indirect greenhouse gas emissions from imported energy: Organizations reporting grid electricity under Category 2 should utilize Electricity Maps Direct Carbon Intensity. This accounts solely for physical emissions occurring at the generation stack during power production, fully satisfying the location-based direct energy imports criteria.
- Category 4: Indirect greenhouse gas emissions from products used by an organization: Upstream emissions associated with fuel extraction, refining, transport, and power generation infrastructure fall under Category 4 (specifically upstream energy-related activities). Reporting entities can natively quantify these emissions by calculating the delta between the Electricity Maps Life Cycle Carbon Intensity and Direct Carbon Intensity. Alternatively, if an organization chooses to report its total energy-related footprint comprehensively within Category 4 under a complete life-cycle boundary, the full Life Cycle Carbon Intensity metric may be applied directly.
By applying this structured allocation, organizations maintain clear reporting boundaries, prevent the double-counting of operational versus upstream supply-chain emissions, and preserve full traceability during third-party ISO 14064-3 verification.
Summary
Electricity Maps carbon intensity to use per Carbon Accounting Standard
- GHG Protocol Scope 2: Direct Carbon Intensity
- GHG Protocol Scope 3: Delta between Life Cycle and Direct Carbon Intensity
- ISO 14064-1:2018 Category 2: Direct Carbon Intensity
- ISO 14064-1:2018 Category 4: Delta between Life Cycle and Direct Carbon Intensity
About marginal emissions
Electricity Maps has worked with marginal emissions for close to a decade, when it decided to discontinue the marginal data offering in 2025 due to concerns about the veracity and verifiability of such signals. You'll find below a list of resources written on the topic, alongside with a list of caveats to consider before using marginal signals.
What marginal emissions are
Marginal emissions are the emissions of the power plant that would ramp up in reaction to an increase in electricity demand (read more in our blog post here). While marginal carbon intensity can be a useful framework for reasoning about what would happen based on a change in behavior, there are some important limitations to keep in mind:
Compatibility with regulation
Marginal emissions are incompatible with most of the reporting guidances, as well as all other major regulation. Recent legislations from the US government and the European Commission prohibit their use. Most importantly, marginal emissions are unsuitable for Scope 2 Accounting (read more here).
Greenhouse Gas Protocol The Scope 2 Guidance writes that “Companies shall not use marginal emission factors [...] for a location-based scope 2 calculation” and that "this guidance does not support an 'avoided emissions' approach for scope 2 accounting"
SBTi The Corporate near-term criteria stipulates that “avoided emissions fall under a separate accounting system from corporate inventories and do not count toward near-term science-based emission reduction targets.”
European Commission On the production of renewable liquid and gaseous transport fuels, it is stated that “the emission intensity of electricity shall be determined following the approach for calculating the average carbon intensity of grid electricity.”
US Department of Energy - Clean Hydrogen "45v" Tax Credit The guidance stipulates that “the level of the credit is based on the lifecycle greenhouse gas ("GHG") emissions that result from the process of producing clean hydrogen.”
Marginal signals oversimplify reality
On the surface, marginal emissions are the emissions caused by the power plant ramping up (or down) in response to a change in consumption. In reality, the electricity grid is a vast and complex interconnected system, having many interdependent components that all affect each other.
Grid operators acknowledge the marginal concept is an oversimplification of the reality they operate in. They state that the accuracy of these signals can't be assessed and verified in practice and therefore caution against their use.
Scientific experts warn about flaws of marginal emissions that prevent them from accurately estimating the impact of load shifting.
The Grid Operator 50 Hertz states that “Determining the correct [marginal] power plant is extremely complex or even impossible. [...] Furthermore, it is never possible to find out retrospectively whether the signal is correct”.
The Grid Operator PJM states that "Because of the various constraints and complexities involved, PJM cannot and does not make any guarantees as to the accuracy of the information nor that it is fit for any purpose."
The Princeton University & NREL state that “Short-run marginal emission factors neglect impactful phenomena and are unsuitable for assessing the power sector emissions impacts of hydrogen electrolysis”.
Public relations risks
At a time when sustainability claims come under heavy scrutiny, verifiability and auditability are key. Auditing a product feature based on marginal emissions is very difficult.
Financial Times Big Tech’s bid to rewrite the rules on net zero: [...] will allow companies to report emissions numbers that bear little relation to their real-world pollution.”
National Resources Defense Council The once in a generation chance to fix corporate emissions reporting: "Some of those global corporate giants are proposing an emissions offsetting approach that will weaken climate targets and open loopholes that allow them to claim success without delivering more ambitious – yet still attainable – climate outcomes."
Action Speaks Louder Hidden Power, Broken Rules: How companies are gaming emissions reporting rules and undermining global climate targets: “[...] pushing for new accounting rules that would allow companies to underreport their emissions by up to 90%.”
Further reading
We've written extensively about marginal emissions in our blog post series:
- Marginal emissions — what they are, and when to use them
- Estimating the marginal carbon intensity of electricity with machine learning
- Our latest research on Marginal emission factors
- Why marginal emission factors are unsuitable for scope 2 accounting
- Marginal vs average: which one to use for real-time decisions?
- Optimizing electricity consumption with a marginal signal may not reduce its carbon footprint
- The challenges of validating marginal signals
- From power markets to reality: Does the marginal power plant really exist?
Selected scientific articles:
- P. Gagnon et al., Short-run marginal emission rates omit important impacts of electric-sector interventions
- Q. Xu et al., System-level impacts of voluntary carbon-free electricity procurement strategies
- R. Bhandarkar et al., Estimating the marginal emissions impact of electric vehicle adoption in the WECC region in 2030
- I. Riepin et al., Spatio-temporal load shifting for truly clean computing
- P. Gagnon et al., Planning for the evolution of the electric grid with a long-run marginal emission rate
- W. Ricks et al., Minimizing emissions from grid-based hydrogen production in the United States
- T. Sukprasert et al., On the implications of choosing average versus marginal carbon intensity signals on carbon-aware optimizations
- P. Grunewald et al., Taking the long view on short-run marginal emissions: how much carbon does flexibility and energy storage save?
External guides & blogs: