The Oyster Edge uses advanced low-power location-solving techniques to provide exceptional battery life - allowing 'deploy once' operation. The batteries will not need to be changed for an assets useful life! This cuts down on cost, effort, and potential issues.
How does it save power?
"Traditional" devices with on-board GPS modules will wake when it is time to get a fix, and start listening for satellite signals. It continues to receive and process these signals, until either:
- a fix is obtained that meets the configured accuracy requirements are met.
- It times out (default timeout 60 sec)
The scanning and processing uses energy. There is an energy cost for every second the module spends on. So fixes that take longer burn up more battery. A typical 'cold start' fix takes around 30 seconds - so if we go undercover where there is no GPS, and the fix fails, we use twice the energy!
In contrast, the Edge simply wakes, scans for GNSS and Wi-Fi signals for around 8-14 seconds. It then passes this raw data to the server. This uses about 1/10th of the energy of on-board GPS! If we are out of GPS coverage, the Edge doesn't waste energy constantly trying for a fix.
The caveat is that the device is not working 'as hard' to keep trying for a more accurate fix. Some fixes obtained via this method may be less accurate than on-board GPS. We are trading ultimate accuracy for battery life. However consider the battery life with hourly updates:
- Oyster3 = 3.5 years
- Oyster Edge = 4.5 years.
Typically we would configure an adaptive tracking mode (more updates on move, less when stationary) instead of hourly updates. But this indicates the battery gain we get with the Edge technology.
Please be aware that these are estimations, and can be influenced heavily by factors such as:
- Application and configuration
- The battery life is dependent on the update rate and other settings
- GSM Reception
- The device may use more energy trying to connect in poor/marginal/no signal conditions
- SIM Card Selection
- Some Roaming SIM cards can trigger lengthy network scans, using up a lot of extra energy, see Roaming SIM Cards - Battery Life Impact
- Mounting position
- This will impact GPS and GSM reception
- Battery type and chemistry
- Different batteries are of different quality and capacity
- Extreme temperatures reduce the lifetime of most battery types.
- BLE Scanning
- Utilising the BLE scan functionality will use energy. Unless explicitly indicated - any of the estimates provided do not incorporate BLE scanning in the calculation.
- Recovery Mode Usage
- Activating Recovery Mode will significantly reduce battery life as the device will 'live track' while it is active.
Periodic Update Estimates
|# of Daily Updates||Battery Life|
*We would not ordinarily configure a device for 24 updates per day using periodic tracking (i.e. hourly updates). We would use 'smarter' adaptive-tracking features.
Movement Based Tracking Estimates
See the calculator attached to this guide.
Recovery Mode Estimates
Since the device updates more frequently on recovery mode, the battery life will decrease significantly. With new batteries in and the device on the move, we should see about 2-3 weeks of battery life.
Network Settings for super-long battery life
In order to maximize battery life, some network settings should be applied - which will allow the device to abort an upload early (within 5 seconds) if it detects it is out of cellular coverage - instead of wasting 3 minutes trying to get on the network! See Critical Parameters - Oyster Edge
Monitoring Battery Status
Make sure to see Battery Level Monitoring [Oyster Edge] for information on how to configure low battery alerts.
Battery Life is more Deterministic (true to calculator)
On the Oyster Edge, a scan takes a similar amount of energy every time, whether we're indoors, outdoors, in a basement etc. The actual result may change (i.e. we may get the location from Wi-Fi instead of GNSS) - but moving to an area out of GPS coverage does not result in the device using extra energy working to get a fix, reducing battery life.
The same can be said if Early Registration Abort is configured, the energy spent on a failed upload is normally about 20x more than a successful one! When enabled, the energy usage is about the same! Energy isn't wasted trying to find the network when out of coverage.
This means that it is easier to predict battery life accurately, as the energy usage isn't dependant on the signal conditions.