What are Locational Marginal Emissions?

LME is a metric that measures the tons of carbon emissions displaced by 1 MWh of clean energy injected to the grid at a specific location and a specific point in time.

LMEs are calculated at each power system node in a manner very similar to the Locational Marginal Prices (LMPs) used to set wholesale electricity market prices. LMEs measure emissions by identifying the marginal generators: the generators that would have been producing energy but for the renewable injection to the grid at that location at that moment. LME data is now available in REmap, learn more.

Measure and maximize carbon impact with LMEs

Technology that provides unprecedented visibility into the projects and activities that maximize your path to decarbonization, and those that don’t.


Better clean energy procurement

LMEs reflect the impact of transmission congestion on carbon emissions and can be used to support granular siting decisions as well as generation technology selection.

Accurate assessment of the carbon value of energy storage

High time-granularity LMEs can accurately evaluate the carbon benefits of energy storage that charges when emissions intensities are low and discharges when emissions intensities are high.

Higher overall carbon abatement per dollar

LMEs support calculation of carbon abatement cost effectiveness metrics for candidate clean energy projects, enabling investors, consumers, and policymakers to maximize the carbon impact of their clean energy program dollars.

Product Offerings

Reporting for existing or planned projects

  • Measure the carbon emissions abated by your actual or planned clean energy purchases, storage developments, or resulting from load center operations.
  • Monitor carbon emissions data over time to track progress towards carbon neutrality goals.
  • Available as a subscription or à la carte analysis to inform clean energy procurement or investment decisions.

API Access

  • Programmatic access to historical LME data for thousands of load and generation node locations at the hourly level for ERCOT, PJM, CAISO, SPP, and MISO, and at the five minute level for PJM.
  • Identify high carbon impact locations and develop siting, technology, and dispatch strategies to maximize decarbonization.


  • REmap offers the ability to view and analyze historical and forecasted LME data for operational wind and solar projects in ERCOT, PJM, and CAISO.
  • Quickly access high quality carbon emissions data paired with generation at the monthly (forecasted and historical) and hourly level (historical only).
  • Learn more at: resurety.com/remap.

Learn how Akamai uses LME data to calculate avoided emissions more accurately, understand why their emissions are what they are, and to evaluate new PPA opportunities.

Broad Reach

Read how Broad Reach Power, a leader in the energy storage space, uses LMEs to measure and communicate the carbon emissions impact of energy storage.

REsurety’s David Luke Oates and Amit Ranjan explain the challenge that LMEs solve.

REsurety’s LME data helps you measure and maximize the carbon impact of each renewable energy project, storage asset, or load center.

The carbon emissions avoided by a given MWh of clean energy varies widely, even across projects located within the same region in the grid. REsurety’s LME technology provides hourly visibility into the projects and activities that maximize your path to decarbonization, and those that don’t. 

Testimonials from REsurety Customers

To decarbonize the fastest and the most cost-effectively, we need to be able to understand the carbon impact of each MWh coming from a specific wind, solar, or storage plant. REsurety’s LME data gives us the transparency we need to make climate-wise investments.

Brian Janous, GM of Energy and Renewables

We are eager to apply this data-driven approach to empower our clients to invest in projects with the largest carbon-reducing impact.

Joan Hutchinson, Managing Director
Marathon Capital

Understanding the carbon impact for all current and future portfolio projects is central to our purpose as a climate positive investor. LMEs offer precision that previously did not exist in the marketplace.

Rich Santoroski, Chief Risk Officer & Co-Head, Portfolio Management

LME data will offer policy makers and consumers the information they need to shift program dollars to where it can make the greatest impact.

Kathleen Spees, Principal
The Brattle Group

REsurety’s LMEs provide us with an extra level of confidence in our calculations.

Mike Mattera, Director of Corporate and Sustainability & ESG Officer
Akamai Technologies

REsurety is tackling a fundamental data gap we have all been grappling with. Reducing carbon emissions by deploying impactful renewables at scale lies at the core of our work.

David Scaysbrook, Managing Partner

Read the white paper

Traditional methods of Scope 2 carbon accounting overlook the meaningful differences between projects and load center locations. Learn more about Locational Marginal Emissions and what REsurety is doing to bring in much needed transparency and accuracy into avoided carbon emissions calculations.