Reefer Container PTI, Genset and Plug-In Charges

The ocean rate on a reefer lane was negotiated to the dollar, yet the landed cost of each box keeps drifting upward by a few hundred dollars or a few thousand rupees. The difference hides in short invoice lines from four different companies: a PTI fee from the line or depot, a genset fee from the trucker, a power fee from the terminal and another from the container freight station. Each line looks reasonable alone, so nobody checks whether two of them billed the same hours.

Those charges can be audited with the same discipline as linehaul if each one is tied to its billing unit and to an event record: a gate interchange, a plug-in log entry or a controller power-on time. Doing that per container typically turns a vague "reefer extras" budget line into a list of specific overlaps, missed free days and duplicate inspections that can be short-paid with evidence.

• What this guide covers: what a pre-trip inspection tests, how genset, power and monitoring charges are billed, who publishes the rates in the US and India, and where the same hours get charged twice.
• What it adds: a worked audit of a US import and an Indian export invoice set, an overlap query you can run on your own data, and contract clauses that cap these charges before the next tender.

Four reefer accessorials, four providers and four billing units

Reefer extras are hard to audit because each one is sold by a different party in a different unit. Before checking any amount, list who performed the service, what physical event started and stopped it, and the unit the price is quoted in. A charge that cannot be tied to an event and a unit should not be approved.

• Pre-trip inspection: performed by the equipment owner or its depot before a box is released empty, priced per container per inspection.
• Genset: a diesel generator set clipped to the container or mounted under the chassis, priced per day, per move or with a minimum, by the trucker or chassis provider.
• Power or plug-in: shore electricity at a terminal, rail ramp, depot or container freight station, priced per 24 hours or part, per day, per shift or per hour.
• Monitoring: manual temperature checks or remote readings logged by the facility or the carrier, sometimes bundled with power and sometimes billed per day.

The same container can therefore attract charges from a shipping line, an empty depot, a drayage carrier, a terminal operator and a CFS within one week. None of them sees the others' invoices. The buyer is the only party that can line the hours up, which is why the audit has to sit with the shipper or its freight audit provider rather than with any single vendor.

What a pre-trip inspection checks before a reefer leaves the depot

A pre-trip inspection proves that a refrigerated container can hold the set point before cargo goes in, and it is the cheapest insurance in the cold chain. Buyers who try to strip it out of the rate usually end up paying more, through rejected loads or claims, than the fee they saved. The audit question is whether each PTI billed was needed and performed once.

A typical PTI covers the box and the machine. Technicians inspect the panels, gaskets, drain and floor; run the controller's automatic test sequence, which exercises compressor, fans, heaters and defrost; check that supply and return sensors read correctly; confirm the unit pulls down to temperature; and record the result against the container number. Many units store the PTI result in the controller, so a download can confirm the test date.

• Standard PTI: the inspection the equipment owner performs before release; some carrier tariffs include it in the freight, others list it as a separate charge.
• Repeat PTI: a second inspection when a box released to the shipper sits too long before loading, under a validity window set in the carrier's own tariff rule.
• Special PTI: extra tests the shipper requests, such as sensor calibration records for cold treatment cargo or checks for controlled atmosphere equipment.
• Shipper-owned box: where the shipper owns the container, the shipper arranges and pays for the inspection directly.

For special inspections, the importing country's treatment protocol, not the carrier, sets what has to be calibrated and recorded. The buyer's job is to request it in writing at booking, so that a special PTI charge has a matching request, and to keep the calibration record with the shipment file in case the treatment is questioned at destination.

Genset charges: clip-on and underslung units, days and minimums

A genset charge pays for diesel power while a reefer is off shore power, mostly during drayage and inland road moves. It should start when the box leaves a plug and stop when it reaches the next one. Billing that runs from the trucker's dispatch to the empty return, regardless of power state, is the most common genset overcharge.

Two designs exist. A clip-on genset hangs on the front of the container and travels with it; an underslung genset is mounted under the chassis and travels with the chassis. That difference matters for billing. A clip-on unit can stay on a box parked at a customer site and keep accruing rent, while an underslung unit leaves with the chassis when the box is grounded, so a grounded box needs shore power or it warms up.

• Per day: each calendar day or 24-hour period the genset is assigned, often with a one-day minimum.
• Per move: a flat fee for a defined trip, such as port to warehouse, regardless of hours.
• Fuel: either included, billed per gallon or litre, or covered by a fuel surcharge; check that fuel is not billed twice through a surcharge and a separate line.
• Empty leg: an empty reefer returning to the depot normally needs no power, so a genset day billed only for the empty return deserves a question.

Regulation can sit inside the genset price. In California, the Transport Refrigeration Unit Regulation in title 13 of the state's Code of Regulations defines a TRU generator set as a generator set that powers electrically driven refrigeration units, including those on shipping containers, and collects unit details for reporting. Operators' compliance costs flow into their rates, so expect lane differences that have nothing to do with fuel.

Genset billing for a reefer container should run only between the out-gate interchange from one powered location and plug-in at the next, recorded on the drayage carrier's interchange receipts; California's TRU Regulation, 13 CCR sections 2477 to 2477.24, also covers these generator sets, so a lane can carry compliance cost alongside the one-day minimum.

Plug-in, power and monitoring at terminals, ramps and CFSs

Shore power is priced by whoever owns the socket, and the billing unit decides most disputes. A terminal that bills per 24-hour period or fraction charges three units for 49 hours; a CFS that bills per calendar day charges three units for a box plugged in at 23:00 and removed two days later at 01:00. Read the unit before reading the rate.

In the US, an ocean carrier's charges reach the buyer through its published tariff and the buyer's service contract. Under 46 CFR 520.4(a)(4), a carrier's tariff must state separately each terminal or other charge, privilege or facility under its control, along with any rules that change or determine the rates. Terminals that bill shippers directly publish their own schedules. A reefer power line on a carrier invoice should point to one of those documents.

Reefer power and monitoring charges passed through by a US ocean carrier must trace to its published tariff, because 46 CFR 520.4(a)(4) requires each terminal or other charge under carrier control to be stated separately; a buyer should match every billed power unit to a tariff rule and to plug-log hours within one billing period.

India splits the source of rates by terminal type. Section 27 of the Major Port Authorities Act, 2021 lets a major port's Board frame scales of rates for access to and use of port assets, while a proviso leaves tariffs on public-private partnership projects to the concessionaire. Most container berths at major ports run under such concessions, and container freight stations set private tariffs, so an Indian reefer export can carry three differently published power rates.

Indian reefer power charges come from three sources: a major port Board's scale of rates under section 27(1) of the Major Port Authorities Act, 2021, a PPP concessionaire's own tariff under the second proviso, and a CFS's private tariff, so an export audit should record which source priced each billed hour.

• Per hour: common where the facility meters reefer points or wants fine billing; check the rounding rule for part hours.
• Per shift or per day: common at CFSs that log reefer temperatures each shift and bill per register entry or calendar day.
• Per 24 hours or fraction: common in terminal schedules; the start time is the main dispute point.
• Monitoring add-on: billed per day or per check where it is not bundled; ask whether readings are manual, remote or both.

Where the same reefer hours get billed twice

Most reefer accessorial leakage is not a wrong rate but the same hours appearing on two invoices, or a clock that starts too early. Four patterns account for most of it, and each one can be caught with event times the buyer already receives or can request. None requires a dispute about price.

• Genset and plug-in overlap: the trucker bills the genset through the day the box was plugged in at the CFS, while the CFS bills power from plug-in.
• Gate-in clock start: the facility bills power from gate-in, though the box sat unplugged on a genset or in a queue for several hours.
• Double PTI: the line bills a PTI under its tariff and the depot bills the same inspection to the shipper's forwarder.
• Bundled monitoring billed again: the terminal schedule includes temperature checks in power, but a monitoring line appears as a carrier pass-through.

The test for each pattern is the same: build one timeline per container from the interchange receipts, plug logs and invoices, then look for intervals that two vendors claim. The query below does that on a simple table of billed intervals and flags any container where genset and power periods overlap by more than a tolerance you set.

-- Billed units and overlap test per container
-- billed_units = CEILING(hours_in_period / unit_hours)
--   unit_hours = 24 for "per 24 hours or fraction", 1 for hourly, 8 or 12 for per shift
-- overlap_hours must be 0; tolerance covers clock drift between vendors

SELECT g.container_no,
       g.vendor            AS genset_vendor,
       p.vendor            AS power_vendor,
       GREATEST(g.start_ts, p.start_ts) AS overlap_start,
       LEAST(g.end_ts, p.end_ts)        AS overlap_end,
       EXTRACT(EPOCH FROM (LEAST(g.end_ts, p.end_ts)
               - GREATEST(g.start_ts, p.start_ts))) / 3600.0 AS overlap_hours
FROM   billed_interval g
JOIN   billed_interval p
  ON   p.container_no = g.container_no
 AND   g.charge_type = 'GENSET'
 AND   p.charge_type IN ('TERMINAL_POWER', 'CFS_POWER')
 AND   g.start_ts < p.end_ts
 AND   p.start_ts < g.end_ts
WHERE  EXTRACT(EPOCH FROM (LEAST(g.end_ts, p.end_ts)
               - GREATEST(g.start_ts, p.start_ts))) / 3600.0 > 0.5
ORDER  BY overlap_hours DESC;

Worked audit: a US import and an Indian export, line by line

A worked example shows how quickly small overlaps add up. The two invoice sets below are illustrative, with assumed rates rather than any terminal's or carrier's published prices, and each line is re-priced from event times. The US box is an import of chilled produce; the Indian box is an export of frozen seafood through a CFS.

In the US case, the terminal billed power on a "24 hours or fraction" basis from plug-in, which was correct, but also added a monitoring line that the buyer's contract bundles into power. The trucker billed three genset days although the box was on genset for under five hours before the receiver plugged it in. In the Indian case, PTI was billed twice and the port clock started at gate-in.

The GST line assumes the supplier treats these as supporting services in transport under heading 9967, where Notification 11/2017-Central Tax (Rate) applies 9% central plus 9% state tax; confirm each supplier's classification and place of supply. Credit on the tax is claimable only on approved lines and subject to the conditions in Section 16 of the CGST Act, so a short-paid line should also be short-claimed.

An Indian export box billed twice in one week

The trace below follows one frozen export container from the empty depot to the port, with illustrative times and document numbers. It shows how three honest invoices add up to an overcharge, because each vendor started or stopped its clock at a different event, and nobody compared them against the controller.

1. 10 June 09:15, empty depot: container released on EIR 55821 with a PTI record dated 9 June; the depot invoices PTI to the forwarder and the line also lists PTI on its export invoice.
2. 10 June 15:40, factory: stuffing ends, set point −18.0 °C, clip-on genset GS-114 running; the trucker's trip sheet opens a genset day.
3. 11 June 14:20, CFS gate-in: the CFS register shows plug-in at 14:55 and genset GS-114 removed at 15:05; the trucker still bills 12 June as a genset day.
4. 13 June 23:10, CFS unplug: box moves to the port; the terminal plug log shows plug-in at 14 June 01:30, but its invoice counts hours from gate-in at 13 June 19:30.
5. 21 June, invoice review: the controller download confirms shore power from 14:55 on 11 June; the buyer short-pays one PTI, one genset day and six port hours with the logs attached.

The controlled version of the same week uses the depot's PTI record as the only PTI evidence, closes the genset clock at the CFS plug-in time, and starts the port clock at the terminal's own plug log. Each vendor still gets paid for what it supplied, and the buyer stops funding the gaps between their clocks.

Rate agreement clauses that cap reefer extras before tendering

Reefer accessorials are cheapest to control in the rate agreement, before the first box moves. Clauses that name the billing unit, the clock-start event and what is bundled leave little room for dispute later. Without them, every invoice becomes a negotiation, and the buyer usually loses because the event records sit with the vendor.

• PTI inclusion: state whether the standard PTI is in the freight, which party pays a repeat PTI, and the trigger for it, such as days between release and gate-in.
• Genset clock: billing from out-gate at one powered location to plug-in at the next, with a stated minimum and fuel treatment.
• Power clock: power from the facility's plug log, not gate-in, with the unit and rounding written out.
• Monitoring: included with power unless a separate service is ordered in writing.
• Evidence on request: the vendor supplies plug logs and controller downloads within a fixed number of days when a line is disputed.

Watch the label as well as the amount. If a carrier bills idle reefer time as detention rather than as power, the US Federal Maritime Commission's billing rule applies, and 46 CFR 541.6 requires the invoice to show the bill of lading and container numbers, free time and its dates, the tariff rule or contract that sets the rate, and a dispute contact. A power line carries no such obligations, so the contract has to supply them.

Which reefer checks a rules engine settles and which need a person

Most reefer accessorial checks are arithmetic on timestamps and belong in fixed rules: overlap tests, billing-unit rounding and contract inclusions. Software can usefully help people read messy evidence, such as controller downloads and free-text invoice lines, but the decision to dispute a charge stays with the buyer who owns the vendor relationship.

Audit checklist and questions for freight audit providers

A buyer can start with the checklist below on one lane for one month, then extend it once the evidence flow works. The questions in the lower rows are the ones to put to any freight audit provider or software vendor that claims to handle reefer accessorials, because most handle rates well and timelines poorly.

Reefer extras sit beside the mode choice itself; our comparison of FCL and LCL break-even shows how fixed per-box charges shift the arithmetic. For the operational side of the same data, see how to judge reefer monitoring by the actions an alarm triggers, which looks at readings rather than invoices, and how to plan reefer breakdown response before a unit fails in transit.

More freight cost guides are on the Logistics and Supply Chain hub. If you want reefer accessorial rules and an overlap check built into your freight audit or TMS, send us a request for proposal with a month of invoices and we will scope the timeline data you need.