SAFE-T User Guide

SAFE-T provides a web-based suite of tools that empower users to:

  • Track Carbon to evaluate Scope 1 emissions from their vessels and fleets aligned with ISO 14083, EN 16258 and EU-MRV reporting requirements.
  • Compare Routes to calculate Scope 3 transport emissions from ships.
  • Compare Alternative Fuels and strategize emissions reduction and efficiency improvements in their maritime operations.

Registration and Login

Users can compare routes and alternative fuels without logging in. To begin navigating the SAFE-T Scope 1 carbon tracking tools, new users must register. User accounts store key data and information for the vessels, fleet and fuel tool inputs.

To begin registration, navigate to the top right-hand corner of the site and select Login. The site will redirect to the Sign In page. Click New User? Click to Register to navigate to new user registration.

Registration requires a username, email, and password. Your preferred password must be provided twice to minimize the chance of typos when creating your account, preventing login issues in the future. After registration, you will be returned to the Sign In page to begin the login process, outlined in the next section User Login. You will not receive a verification email, there are no additional steps to register your new account.

To access your previously registered account, navigate to the top right-hand corner of any page and select Login. On the Sign In page enter the Username and Password previously registered with your account.

Check the Remember Me toggle to stay logged into your account on your device and its current browser. This saves time when accessing your account from a trusted device, without having to enter your username and password on each visit. If you are using a public or shared device, that others have access to, it is not recommended to select Remember Me.

If you have forgotten your password, suspect unauthorized access to your account, or cannot complete the steps for User Login, users can reset their password from the Sign In page. Below the username and password inputs, users will see: Forgot your password? Click to Reset. Click this link to navigate to your account password reset and enter the email associated with your account and then select the Request Password Reset button. You will receive an email with a link and instructions to reset your password.

If you do not receive the email within a few minutes, please check your spam folder and/or confirm that you correctly submitted your reset request. Incorrectly entered emails will see an error message on the Reset Password page: “User email does not exist. Please check the email and try again.”

If you have not requested a password reset or have managed to access your account with your previous password, you can simply ignore the email and its message then return to navigating the SAFE-T site.

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From the SAFE-T Homepage, users can navigate to the tools in two pathways.

  1. Scrolling towards the bottom of the Homepage, users will see three boxes designating the primary three tools of SAFE-T and text with brief descriptions of each. Select one of Track Carbon, Compare Routes, or Compare Fuels to navigate to the appropriate tool page.
  2. At the top of the SAFE-T site, accessible from any page, you will see a drop-down menu for Tools▾. Clicking this menu will drop-down to list the three tools: Carbon Tracking, Compare Routes, or Compare Fuels. Clicking any of these will take you to the appropriate tool page.
Track Emissions
Compare Routes
Graph down
Compare Alternative Fuels

Carbon Tracking

The SAFE-T Carbon Tracking tool allows users to track carbon emissions based on fuel consumption over time. Carbon Tracking uses international standards, including ISO-14083 and EU EN16258, and allows users to enter data in a format consistent with EU-MRV reporting requirements. Carbon Tracking can be performed for the fleet and/or vessel-voyage scopes of fuel and carbon use. The additional SAFE-T tools allow comparison of different routes’ carbon intensity from the user provided data.

Your privacy is critically important when using SAFE-T. All of your data inputs saved within the SAFE-T Tools are treated securely and confidentially.

Navigating to the Carbon Tracking tool page, users will see a brief overview of the tool, including a summary of the most recently entered user data. Users can choose whether to enter and observe data at the fleet and/or vessel-voyage scopes by navigating using the respective buttons for Fleet or Vessel. The following sections will help you navigate through either of these choices.

Upon navigating to the Fleet Reporting page, users can analyze their fleet-specific data for the Carbon Tracking tool. First time users can first navigate to either Vessel Reporting or Account Management pages to enter their vessel-specific information and ‘build’ their complete fleet data. Fleet Reporting can be either Annual, Quarterly, or Monthly. Clicking one of these buttons will advance the user to the proper fleet-level reporting page, with its necessary user input field forms.

Fleet-level data input fields include:

  • Year* [drop-down]
  • Quarter or Month [drop-down]
    • This field only appears on the relevant quarterly or monthly forms
  • Fuel Type* [drop-down]
  • Fuel Consumed (Metric Tons)*
  • Fleet Nautical Miles*
  • Fleet Deadweight Tons
  • Fleet Tons of Cargo (Metric Tons)
  • Fleet TEUs

*Required field

If the user’s fleet used multiple fuels over the period, they should be entered separately, ensuring that the fuel consumed, nautical miles, and cargo parameters correspond to the fuel being entered.

Calculations of carbon intensity and transport work, i.e. gCO2e/TEU-km, can only be computed if the transport work data are entered.

If you notice an error in the data entered, delete the row from the table above and re-enter the data.

Upon navigating to the Vessel Reporting page, users can enter or analyze vessel-specific information for the Carbon Tracking tool. First time users must first enter a vessel list by navigating using the button Enter vessels here to be redirected to the Vessel List page. On this page, users can enter vessel information about their vessels. These fields are designated to capture accurate and detailed data, complete each as accurately as possible to facilitate the best experience and results. These user input vessel fields include:

  • Vessel ID* (e.g. IMO Number, USCG number)
  • Vessel Name*
  • Ship Type [drop-down]
  • Deadweight Tonnage
  • Gross Tonnage
  • TEU Capacity
  • Total Main Engine Power (kW)
  • Total Auxiliary Engine Power (kW)
  • Total Boiler Power (kW)
  • Built (year)
  • Design Speed (kts)
  • Design Draft (ft)
  • Primary Fuel Type [drop-down]
  • Secondary Fuel Type [drop-down]

Only Vessel ID and Vessel Name are required to for emissions estimates, however more information provided results in better record keeping for the user. After user input, the Add/Edit Data button must be selected to save the information to your SAFE-T account and for use in the site’s tools.

Vessel-specific information can also be added or edited through the Account Management page, accessible in the top right-hand corner by clicking Logged in as [username]. Clicking this will take users to a series of link connections to edit their stored information. Vessel-specific information can be accessed using See/Enter Vessel Information. Additional links allow users to edit their profile information, enter annual/quarterly/monthly fleet fuel data, or enter vessel fuel data. The user input fields for vessel reporting, accessed through this pathway, are the same as outlined above.

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Compare Routes

Upon navigating to the Routing page, users can estimate Scope 3 ship transport emissions by entering travel-specific data for the Compare Routes emissions tool. Users will enter information about their origin, destination, and cargo volume to estimate ship transport carbon emissions.

Ports may be selected through a drop-down menu for the Origin or Destination. Users can begin typing a UN/LOCODE or city to select a port. Users may enter either TEUs or cargo tons to provide their cargo volume (1 TEU = 10 tons, as defined by CCWG).

Route-level data input fields include:

  • Origin Port
  • Destination Port
  • Route TEUs
  • Cargo Tons
  • Reefer ⊠ toggle, for refrigerated cargo

The routing output will display the route on a map that users can interact with, as pictured below. Beneath the map, users can view the route name and key emissions information in CO2 equivalent units (CO2e), used to weight greenhouse gas emissions to consider global warming potential. It allows for a streamlined comparison of results for Route CO2e and Total CO2e under a standardized metric, key for climate impact assessments.

Carbon emissions are calculated in accordance with the Clean Cargo Working Group (CCWG) Methodology using trade lane average emission factors for refrigerated and non-refrigerated containers. The CCWG 70% utilization factor is applied and distances are based on our routing network which uses actual routes sailed or shortest distances between ports. 1 TEU = 10 tons.

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Compare Alternative Fuels

Upon navigating to the Compare Fuel Properties page, users can analyze fuel-specific data considering the properties of marine bunker fuels with the Compare Alternative Fuels tool. Users can compare the average properties of two fuels, from a database of fuel-specific data informed by a vast collection of sources and literature.

Users have access to reliable and up-to-date information when evaluating and comparing fuel choices. The Compare Alternative Fuels tool considers the full lifecycle in its fuel properties and allows users to specify the production pathways when selecting a fuel (e.g. grey to green sourcing for renewables).

Select two fuels [by drop-down menu] to compare. Output will include: Storage Pressure (bar), Storage Temperature (°C), Energy (reported in MJ/kg and MJ/L), Well-to-Wake Carbon Intensity (WtW CO2e/MJ), and Cost per Unit Energy ($/MJ).

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Decarbonization Resources

On the navigation bar at the top of the page users will see a link to the Resources page. Clicking this will navigate to a valuable hub of information for users to learn or stay informed about emissions and low-greenhouse gas fuels. This page serves as an excellent starting point for users that may not be familiar with key decarbonization terms, such as emission scopes. Further information summarizing key findings on alternative fuels can also be found on the Resources page.

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SAFE-T Methodology

The SAFE-T suite of tools was designed to empower users by integrating international standards and methodologies for estimating emissions in an accessible format. Grounded in the collaborative and informed work of ISO 15083 and EU EN16258, SAFE-T not only provides a reliable framework for emissions assessment, but also ensures that the data input aligns with EU-MRV reporting requirements. Thereby, offering users a comprehensive and streamlined solution to navigate climate action within the maritime industry. In this section, we summarize the methodologies that underpin the SAFE-T tools.

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European Standard EN 16258:2012

European Standard 16258:2012, titled “Methodology for calculation and declaration of energy consumption and GHG emissions of transport services (freight and passengers)” establishes a common methodology for the calculation of energy consumption and GHG emissions from transport services, including oceangoing vessels.

European Standard 16258:2012, titled “Methodology for calculation and declaration of energy consumption and GHG emissions of transport services (freight and passengers)” establishes a common methodology for the calculation of energy consumption and GHG emissions from transport services, including oceangoing vessels.

Calculations consider all vehicles used to perform transport service, all fuel (or fuel equivalents) used by each vehicle, and all loaded and empty trips made by each vehicle. Calculations produce four outputs

  • Well-to-wheels (WTW) energy consumption
  • Well-to-wheels (WTW) GHG emissions
  • Tank-to-wheels (TTW) energy consumption
  • Tank-to-wheels (TTW) GHG emissions

Note that WTW and TTW terms may be used to refer to on-road transportation fuel cycle emissions. In the context of waterborne transport under the EN 16258:2012 standard, WTW and TTW may be thought of as referring to Well-to-Wake and Tank-to-Wake emissions. For clarity and consistency, we use the terminology from the standard.

The steps for calculating energy consumption under EN 16258 are as follows:

  1. Identify the different legs of transport service;
  2. Calculate energy consumption and GHG emissions for each leg;
    1. Establish the vehicle operating system (VOS) related to the leg;
    2. Quantify total fuel consumption for the VOS;
    3. Calculate total energy consumption and GHG emissions for the VOS, including WTW, TTW using fuel-specific emission factors;
    4. Allocate emissions (WTW, TTW) to passengers and cargo, considering distance i.e., gCO2e/pax-km, gCO2e/tonne-km, gCO2e/TEU-km;
  3. Sum results for each leg.

Calculation of energy consumption for legs under Step 2 also considers operational parameters including:

  1. Fuel consumption, by type of fuel
  2. Distance
  3. Fuel consumption per unit distance
  4. Load
  5. Load factor
  6. Vehicle capacity
  7. Empty distance or lading characteristics

Fuel-specific energy and emission factors (CO2e) for TTW and WTW GHG emissions are provided in the standard and may be substituted for country- or region-specific values where known and appropriate. When reporting, users are required to provide a statement that the results were prepared in accordance with the standard EN 16258:2012, as well as declarations on energy consumption and GHG emissions (TTW and WTW), including units. Energy and GHG emission factors are given in Appendix A of the standard.

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ISO/DIS Draft Standard 14083

The draft international standard ISO/DIS 14083, titled “Greenhouse gases — Quantification and reporting of greenhouse gas emissions arising from transport chain operations” aims to provide an international standard for estimating GHG emissions from transportation sources, including oceangoing vessels.

The draft standard provides a detailed methodology to be followed by practitioners. The proposed standard covers:

  • all vehicle operational processes;
  • all transport hub processes;
  • all energy carriers used by each vehicle/hub;
  • all loaded and empty trips made by each vehicle;
  • start up and idling, transshipment, (de)boarding, and pipelines.

The implementation of the draft ISO 14083 standard in SAFE-T relies upon reporting of total fuel consumption, which is then multiplied by the relevant emission factor to estimate carbon emissions.

GHG emission factors and sources are provided in the draft standard for European and North American values. Sources include other ISO standards related to life cycle assessment, EU Standard 16258:2012, the GREET Model, and grid-specific emission factors. The ISO 14083 standard also considers metrics for freight and passenger transport work

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Vessel Routing

SAFE-T tool to Compare Routes and compute Scope 3 transport emissions is built on existing route data, calculated by AIS data of traveled vessels, and informed by the methodologies and trade lanes of the Clean Cargo Working Group (CCWG).

The CCWG developed average CO2 emission factors for the main trade lanes, to allow results based on limited knowledge of origin/destination and trade lane. This approach is considered to be a transportation model ‘best practice’ to collect and calculate CO2 emission data for ocean transport.

The CCWG methodology is based on the European EN 16258 standard, the IMO’s EEOI guidelines, and the GHG Protocols supply chain guidelines. The CCWG methodology applies only to CO2 emissions from ocean-going container ships. Other vessel types and waterborne transport are covered under the GLEC framework.

The CCWG methodology uses trade lane specific CO2 emission factors, along with voyage distances and cargo volumes to estimate total CO2, as follows

$$ \text{Total}_{CO_{2}} = \text{Trade Lane}_{CO_{2}} \times \text{TEU} \times \text{Distance}_{km} / 70\% $$


  • \(\text{Trade Lane}_{CO_{2}}\) is the trade lane-specific CO2 emission factor (CO2/TEU-km), periodically updated by CCWG based on reports submitted by members
  • \(\text{TEU}\) is the count of TEUs being shipped (assuming 1 TEU = 10 tons)
  • \(\text{Distance}_{km}\) is the port-to-port distance (km)
  • 70% is the CCWG average percent utilization factor

The CCWG methodology estimates TTW CO2, claiming a lack of consensus on the upstream portion of emissions. We present TTW CO2. The CCWG methodology points to the IMO’s default global average WTW CO2 data to adjust heavy fuel oil (HFO) and marine diesel oil (MDO) emissions, to generate WTW estimates of total carbon emissions.

Fuel Ratio of gCO2 WTW to TTW
HFO 1.086 gCO2 WTW / gCO2 TTW
MDO 1.212 gCO2 WTW / gCO2 TTW

The CCWG Methodology is summarized in six steps:

  1. Identify and map trade lanes
  2. Identify number of containers (or container equivalents) on each trade lane
  3. Estimate distance traveled between relevant port pairs along each trade lane
  4. Multiple trade lane average emission factors by the number of containers (or container equivalents) and the estimated distance between ports
  5. Sum up all trade lane CO2 emissions
  6. Provide Carbon Calculation Clause

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SAFE-T: Ship Alternative Fuel and Emissions - Toolkit

Developed with funding from the U.S. Department of Transportation - Maritime Administration (MARAD) Maritime Environmental and Technical Assistance (META) Program.


© 2024 Energy and Environmental Research Associates, LLC.