Vessel carbon rating

Carbon rating reports a vessel's emissions efficiency alongside its compliance result. You ask for it when you register the vessel, and read it back from GET /carbonrating once the screening has finished.

Carbon rating is an addon

It is available to subscribing customers only. Contact your Pole Star representative to have it enabled on your account.

Ask for it at registration

Carbon rating is part of the screening, not a separate call, so the vessel has to be registered with it switched on. Add carbon_rating to the POST /registration body.

Screening a Vessel covers the rest of registration and how to tell when the screening has completed.

Find the id

Carbon rating results hang off their own screen result id. In the screen_results array returned by GET /transaction, find the object whose check is CARBON_RATING.

{
  "check": "CARBON_RATING",
  "creation_date": "2022-05-05T14:01:31Z",
  "id": 4261273,
  "resource_uri": "/api/v1/screenresult/4261273",
  "result_code": null,
  "status": "OK"
}

Retrieve the rating

Pass that id as the screenresult parameter.

{
    "meta": {
        "limit": 20,
        "next": null,
        "offset": 0,
        "previous": null,
        "total_count": 1
    },
    "objects": [
        {
            "aer_alignment": 1.0100000000000002,
            "annual_efficiency_ratio": 4.62,
            "annual_efficiency_ratio_unit": "AER [gCO₂ / dwt · n miles]",
            "breadth": 32.26,
            "dead_weight": 63242.0,
            "depth": 18.5,
            "id": 8035,
            "length": 199.9,
            "name": "BERLINDA",
            "peer_group_size": 1892,
            "percentile": 0.0,
            "poseidon_principles_aer_trajectory_value": 3.61,
            "rating": 30,
            "rating_date": "2023-04-15",
            "rating_median": 8.03,
            "rating_peer_group_def": "Bulk Carrier, Deadweight 63242 +- 10.0%",
            "reporting_year": 2021,
            "resource_uri": "/api/v1/carbonrating/8035",
            "screenresult": "/api/v1/screenresult/4261273",
            "severity": "WARNING",
            "ship_type_level4": "Bulk Carrier",
            "source_method": "Matching to sister ships",
            "source_name": "Derived from sibling vessels in the EU MRV",
            "transport_work_emission_factor": 7.64,
            "transport_work_emission_factor_unit": "Annual average CO₂ emissions per transport work (mass) [g CO₂ / m tonnes · n miles]"
        }
    ]
}

What the response tells you

The headline figures are annual_efficiency_ratio, the vessel's AER for the reporting_year, and severity, the band PurpleTRAC puts that figure in. Severity bands are set by your account configuration, so the same AER can read OK on one account and WARNING on another.

The rest gives you the context to defend the number:

rating_peer_group_def and peer_group_size say which vessels the rating was compared against, here 1,892 bulk carriers within 10% of the same deadweight. rating_median and percentile place the vessel inside that group.

poseidon_principles_aer_trajectory_value is the Poseidon Principles trajectory for the vessel, and aer_alignment its position against it.

source_name and source_method say where the figure came from. A vessel that reports to the EU MRV directly reads differently from one whose figure is derived from sister ships, and this example is the second kind.

Dimensions travel with the record too: length, breadth, depth, dead_weight and ship_type_level4.

Screening Vessels

Registration, the transaction id, and reading screen_results.

Getting Started

Which addons your account configuration gates, and what a 403 means.

Additional Checks

The other detailed checks a screening produces.

Ask for it at registration#

Find the id#

Retrieve the rating#

What the response tells you#

Related#

Ask for it at registration

Find the id

Retrieve the rating

What the response tells you

Related