IMOS - Offhire Emissions

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Overview

When a vessel goes offhire, for example, dry dock, repairs, breakdown, or a delay event at an EU port, it can still consume fuel and incur EU ETS allowance costs and FuelEU Maritime compliance obligations. Previously, there was no way to track the emissions generated during an offhire period, attribute them to EU ETS or FuelEU, or flow the resulting costs through the Voyage P&L.

The offhire emissions workflow in IMOS calculates EU ETS and FuelEU emissions for each delay you enter on the Delays form, exposes the per-delay totals in the Carbon Calculator, and surfaces the resulting costs in a dedicated section of the Voyage P&L. From there, the costs can flow into the related Time Charter invoicing and FuelEU pooling workflows.

This article describes how to configure offhire emissions, how IMOS calculates them, and where the results appear.

Configuration Flags

Offhire emissions are governed by four configuration flags. Each one controls a separate layer of the workflow: calculation, defaulting, P&L exposure for EU ETS, and P&L exposure for FuelEU. These flags are designed to work in tandem, and turning on some while leaving others off results in gaps. The suggested order for enabling them is calculation first, followed by defaulting, and finally the two P&L flags.

CFGCalculateOffhireEmissions

When enabled, FuelEU and EU ETS emissions are calculated for each offhire delay based on the From/To period entered on the Delay form.

The calculation is only triggered when the TCI Emissions or TCO Emissions check box on the row is selected. Selecting the row alone is not enough.

CFGDefaultQtyEmissionsOffhire

Controls whether the Qty Emissions check box on the Delay form is pre-selected when you enter a new offhire delay row. Existing delays are unaffected. This flag only changes the default state for newly added rows.

The Qty Emissions check box is the switch that tells IMOS which calculation mode to use for the delay (see Calculation Modes below). Enabling this flag is recommended for accounts where the majority of offhire delays should be treated as Qty-based, because it removes a per-delay manual step. Disable it if Qty mode is the exception rather than the rule, to avoid accidentally selecting the checkbox for delays that do not require it.

CFGEnableOffhireEmissionsPnl

When enabled, a new Offhire Emissions section appears in the Voyage P&L. The EU ETS amounts in this section are driven by the calculated offhire emissions for each delay, multiplied by the relevant carbon price. The corresponding bill code is OHCARBON, and amounts are routed via a dedicated business rule.

The flag also exposes the Offhire Qty and Offhire Amt columns in the Cash Invoices section under the EU ETS tab of the Time Charter In contract, so that EU ETS offhire amounts can be included on cash invoices and carbon allowance invoices.

CFGEnableOffhireFuelEUPnl

When enabled, FuelEU offhire costs appear in the Voyage P&L under the same Offhire Emissions section. The corresponding bill code is OHPENALTY.

FuelEU offhire amounts also flow into the Time Charter Payment workflow.

Select Make Payment → Create Add Details → Fuel EU Penalty, and the Offhire Fuel EU Penalty line appears for inclusion on the TC invoice. IMOS includes the same amounts when generating FuelEU pooling journals.

Entering Offhire on the Delays Form

Offhire emissions are derived from the records you enter on the Delays form. The following fields and check boxes determine how emissions are calculated for each delay.

• From and To: The start and end of the offhire period. These dates define the window used to apportion emissions across the affected port and sea legs.

• TCI Emissions: Select this check box to calculate offhire emissions for the Time Charter In side of the voyage. Emissions are calculated only when this check box is selected.

• TCO Emissions: Select this check box to calculate offhire emissions for the Time Charter Out side, for TCTO voyages.

• Qty Emissions: When selected, the offhire calculation uses the manually entered fuel quantity from the Bunkers tab on the delay. When cleared, the calculation apportions emissions based on the From and To dates only.

Calculation Modes

The combination of Qty Emissions and TCI Emissions or TCO Emissions determines which of two calculation modes IMOS uses.

Mode 1: Qty Emissions with TCI Emissions or TCO Emissions

Used when both Qty Emissions and TCI Emissions (or TCO Emissions) are selected on the delay row.

The delay hours field is ignored. Instead, IMOS allocates offhire bunker consumption to the delay using the manually entered fuel quantity on the Bunkers tab, weighted by the intersection of the delay window with the port or sea leg it overlaps.

Use this mode when you have a reliable bunker reading for the offhire period – for example, a dry dock with documented consumption.

Mode 2: TCI Emissions or TCO Emissions

Used when TCI Emissions (or TCO Emissions) is selected but Qty Emissions is cleared.

IMOS uses the delay’s From and To dates to allocate the port or sea leg’s emissions over the delay window. The manual quantity and delay hours fields are not consulted.

Use this mode when no specific bunker reading exists for the offhire period and you want IMOS to estimate emissions from the leg’s overall consumption profile.

How Allocation Handles Boundaries

The allocation logic depends on where the delay falls relative to the voyage itinerary:

• Delay covers an entire port stay: The full port emissions are treated as offhire.

• Delay covers an entire sea leg: The full sea leg emissions are treated as offhire.

• Delay covers a partial port stay or sea leg: The portion of the port or sea leg that falls inside the delay window is treated as offhire; the rest remains on-hire.

• Delay crosses the boundary between a port stay and a sea leg: Emissions for each affected portion are apportioned independently and then summed.

Multi-year Delays

When a delay spans more than one EU ETS phase-in year — for example, a delay that begins in 2025 and ends in 2026 — IMOS splits the delay at the year boundary. The applicable phase-in percentage (70% for 2025, 100% for 2026) and the year-appropriate emission factors are applied to each segment. Both segments are summed and reported under the same delay in the Voyage P&L. For more information on phase-in logic, see the IMOS - Carbon Calculator article.

TCTO Rebill Voyages

For voyages with offhire rebills (TCTO voyages with both TCI% and TCO% set), each side is calculated independently. Each delay surfaces as both an Offhire Emissions line and an Offhire Rebill Emissions line in the Voyage P&L.

End-to-End Workflow

1. Set up the configuration

   1. Enable the three flags.

   2. Confirm schema version is 51.8 and above.

   3. Add the new business rule if it is not already present (in most environments it ships automatically after the flag is on).

2. Enter the delay

   1. In Voyage Manager → Delays, add the delay row with Activity, Reason, From/To dates, and bunker quantities as usual.

3. Select the calculation mode

   1. Confirm the Qty Emissions check box state (defaulted via CFGDefaultQtyEmissionsOffhire) and select TCI Emissions and/or TCO Emissions as appropriate for the contract structure.

4. Click Save

   1. IMOS calculates the FuelEU and EU ETS emissions for the delay period.

5. Review the Carbon Calculator

   1. Open Voyage Manager → Sustainability and confirm the per-delay emission totals appear on the FuelEU and EU ETS tabs.

6. Confirm the Voyage P&L

   1. Open the Voyage P&L. The Offhire Emissions section lists each delay with its period range and regulation breakdown. If a delay's Include in PnL check box is cleared in the Carbon Calculator, that delay's line is suppressed from the section.

7. Invoice (separate workflow)

   1. With CFGEnableOffhireFuelEUPnl enabled, the FuelEU portion flows onto the TC invoice (bill source VFEUE, subcode OHPENALTY) and is deducted from pooling journals; the EU ETS portion is handled via cash or allowance invoices.

Viewing Offhire Emissions in the Carbon Calculator

After offhire emissions are calculated, the following fields appear in the Carbon Calculator in the Voyage Manager:

• EU ETS - Offhire Net Emissions MT: The net EU ETS emissions associated with offhire periods on the voyage.

  

• FuelEU - Offhire Net Compliance Balance MT: The net FuelEU compliance balance impact associated with offhire periods on the voyage.

These fields let you see the impact of offhire on total voyage emissions without inspecting each delay individually.

Offhire Emissions in the Voyage P&L

When CFGEnableOffhireEmissionsPnl or CFGEnableOffhireFuelEUPnl is enabled, an Offhire Emissions section appears in the Voyage P&L. The section breaks emissions down two ways:

• Per delay and per period: Each offhire delay appears as its own line, with the period range in the description, so that multiple offhires on the same voyage remain distinguishable.

• Per regulation: EU ETS and FuelEU values are reported separately.

A second line, Offhire Rebill Emissions, appears alongside the main line for TCTO and other rebill scenarios.

The amounts are calculated using:

MT × Cost/MT ÷ Exchange Rate

where MT is pulled from the Carbon Calculator output for the matching delay. The corresponding bill codes are OHCARBON for the EU ETS portion and OHPENALTY for the FuelEU portion; both are routed via a dedicated business rule.

For more information on business rules for EU ETS and FuelEU https://vesonjira.atlassian.net/wiki/spaces/WIP/pages/edit-v2/4979261475?draftShareId=c0d25d60-5114-4d66-8d5e-9e41f011d35a.

Invoicing Offhire Emissions

When the relevant Voyage P&L configuration flag is enabled, offhire emissions can be invoiced as follows:

• EU ETS offhire emissions (CFGEnableOffhireEmissionsPnl enabled): Offhire emission costs are available for inclusion on carbon allowance invoices and cash invoices on the related Time Charter contract. The Offhire Qty and Offhire Amt columns appear in the Cash Invoices section under the EU ETS tab of the Time Charter In contract. After you create an invoice, the Offhire Emission Cost is connected to the Emission Cost and is included as a rebillable for the Time Charter.

• FuelEU offhire emissions (CFGEnableOffhireFuelEUPnl enabled): Offhire emission costs are available for inclusion on TC invoices via Make Payment → Create Add Details → Fuel EU Penalty, where Offhire Fuel EU Penalty appears in the Time Charter Payment. The same amounts are considered when generating FuelEU pooling journals.

FAQ

Q1: I enabled CFGCalculateOffhireEmissions but I am not seeing emissions on my delay.

• Confirm that TCI Emissions (or TCO Emissions) is selected on the delay row. The calculation is gated on that check box — the configuration flag is only the master enable.

Q2: My Voyage P&L does not show the Off-hire Emissions section.

• Three things to verify:

  • CFGEnableOffhireEmissionsPnl is on.

  • Database schema is 51.8 or higher.

  • The Include in PnL check box is selected on the Carbon Calculator FuelEU/EU ETS tab(s).

Q3: Do I need CFGEnableOffhireFuelEUPnl for the Voyage P&L section to appear?

• No. CFGEnableOffhireEmissionsPnl handles the Voyage P&L display. CFGEnableOffhireFuelEUPnl is only needed if you also want the FuelEU offhire amounts to flow into TC invoices and pooling journals.

Q4: If I duplicate an offhire row, do I see two P&L lines?

• Yes. The Off-hire Emissions P&L section distinguishes duplicate delays by the period range in the description, so each line is identifiable. This is by design for cases where the same delay window needs to be apportioned across multiple cost categories.

Q5: How is a delay that crosses 2025 → 2026 handled?

• The proration splits the delay at the year boundary and applies each year's phase-in percentage (70% for 2025, 100% for 2026) and that year's emission factors to its respective segment. Both segments are summed and reported under the same delay in the Voyage P&L.

Q6: Does turning on CFGDefaultQtyEmissionsOffhire change existing delays?

• No. The flag only changes the default state of the Qty Emissions check box for new offhire delay rows added after the flag is enabled.