Vehicle tracking is a solved problem because vehicles have engines, and engines have power. Trailer tracking and container tracking are harder for exactly that reason: a trailer sitting in a yard has no power source, no ignition to signal activity, and often no fixed home. It also spends most of its life detached from whatever last towed it, which is precisely when it goes missing, gets used by someone else, or quietly sits idle for weeks while you pay for it. This guide covers how tracking unpowered assets works and what to look for.
Why unpowered assets get lost
Ask a logistics operator how many trailers they own and you will get an exact number. Ask where each one is right now and the answer becomes vaguer. Trailers and containers move between sites, get dropped at customer yards, get borrowed between depots and occasionally do not come back. Because no single person is responsible for one at any given moment, nobody notices when it stops being where it should be.
The result is a familiar set of costs: renting extra units while owned ones sit forgotten, staff time spent phoning around to locate an asset, demurrage on containers not returned in time, and outright loss. Each of these is a visibility problem before it is a money problem.
How trailer and container tracking works
The tracking principle is the same as any GPS device, explained in our guide to how GPS vehicle tracking works. The difference is entirely about power. Without a vehicle battery to draw from, an asset tracker has to run for a long time on its own, which shapes everything about how it behaves.
There are three common approaches:
| Type | Power source | Reporting | Best for |
|---|---|---|---|
| Long-life battery tracker | Internal battery, often lasting years | Scheduled: a few times a day, more when moving | Containers, skips, plant, dropped trailers |
| Solar-assisted tracker | Small panel plus battery | Frequent, near-continuous while charged | Trailers and equipment kept outdoors |
| Powered when connected | Trailer electrical connection when coupled | Live while towed, low-power when parked | Trailers that are regularly coupled to tractors |
The trade-off is always the same: report more often and the battery drains faster. This is why asset tracking is usually designed around scheduled check-ins rather than the second-by-second updates you would expect on a vehicle.
Motion-triggered reporting: the practical compromise
The smartest asset trackers solve the power problem by changing behaviour based on movement. While the trailer is parked, the device reports its position a small number of times per day, which is entirely sufficient for something that is not going anywhere. The moment its motion sensor detects movement, it wakes up and reports far more frequently.
This gives you the two things you actually need: a reliable answer to “where is trailer 14” at any time, and live tracking during the periods that matter, whether that movement is a scheduled trip or a theft. It is also why battery life claims should always be read alongside the reporting profile they assume.
What tracking changes day to day
- Utilisation becomes visible. You can see which trailers are working and which have not moved in a month, which is usually the fastest route to reducing rental spend.
- Yard checks stop being manual. A map replaces the walk-around and the phone calls.
- Detention and demurrage become provable. Geofenced arrival and departure timestamps show exactly how long an asset sat at a customer site.
- Theft is detected quickly. Movement outside expected hours triggers an alert instead of being discovered days later.
- Maintenance can be scheduled. Distance travelled per trailer supports servicing based on use rather than a fixed calendar.
Geofencing does much of this work, and the same principles covered in geofencing for fleets apply to yards, depots and customer sites.
Choosing an asset tracker
Work through these in order:
- Battery life at your reporting rate. Ask for the figure at the profile you will actually use, not the best case.
- Motion-triggered wake-up. Without it you are choosing between poor battery life and poor visibility.
- Mounting and environment. The device will live outdoors through rain, dust and heat, and it needs to attach somewhere concealed and secure.
- Tamper and removal alerts. Anything detachable will eventually be detached, deliberately or otherwise.
- One platform for everything. Trailers on one system and vehicles on another means nobody sees the whole picture.
That last point matters more than it first appears. The value of trailer tracking multiplies when it sits beside vehicle tracking, because you can see which tractor is nearest to which trailer, and whether an asset dropped at a site is due for collection. Both live on the same map on the Fleetile platform.
Beyond trailers and containers
The same battery-powered approach applies to any valuable thing that moves but has no power of its own: generators, compressors, site equipment, skips, agricultural implements and portable cabins. Construction and agriculture both run on exactly this kind of asset, which is why the ideas here overlap with fleet tracking for construction equipment. If it is expensive, portable and occasionally goes missing, it is a candidate for asset tracking.
Frequently asked questions
How does trailer tracking work without power?
The tracker runs on its own long-life battery, sometimes assisted by a small solar panel or by the trailer’s electrical connection when coupled. To conserve power it reports on a schedule while parked and switches to frequent reporting when its motion sensor detects the asset moving.
How long does an asset tracker battery last?
It depends almost entirely on how often the device reports. A tracker checking in a few times a day can run for a long period, while one reporting continuously will drain quickly. Always ask for battery life at the reporting profile you intend to use rather than the headline figure.
Can container tracking work at sea or in a stack?
GPS needs a view of the sky, so a container buried in a stack or below deck will not get a fix. The tracker stores what it can and reports again once it has sky visibility, which in practice means you get reliable positions at each end of the journey and gaps in between.
Will tracking tell me if a trailer is loaded?
Basic trackers report position and movement only. Load status requires additional sensors, such as a door sensor or a weight or axle-load input, which can be added where knowing empty versus loaded matters to your operation.
Is asset tracking worth it for low-value equipment?
Compare the tracker cost against the replacement cost plus the disruption of losing the item at the wrong moment. For genuinely low-value items it often is not worth it, but many fleets underestimate the cost of downtime and of renting a replacement while an owned asset sits somewhere unknown.
Put every asset on one map
Vehicles, trailers and equipment belong on the same screen. Get a Fleetile demo and see how asset tracking fits alongside live vehicle tracking.
