Computing Battery life for a gas meter module
AMI is pretty standard and now we also hear about MGL and IGL getting into AMI based on LoRaWAN. Here we compute the battery life for a LoRaWAN module for the standard Gas meters used in India
A typical gas meter indicates Qmax of 2.5m3/ hour which would mean 2.5*1000 rotations of the LSB every hour. Making the standard assumption that one of the digits in the LSB worm has the magnet, the MCU is triggered at roughly 14.5 seconds.
Taking the MCU current at 10mA and computation time of 100ms, we are looking at a 0.070mAH where we assume the meter will be running at the maximum capacity always.
Now, further, we add two transmissions a day of LoRaWAN packets, adding some more stress on the energy requirement (6uAH).
With the above, if you take a battery capacity of 1500mAH, about 2.4 years is a pretty standard life expectation from the battery where the meter is used at its peak ability and 2 LoRaWAN updates are sent every day.
The average consumption for a home is about 1m3/ day and the best implementation with an energy-efficient MCU will consume much fewer resources, so the battery self-discharge may be a bigger worry than anything else.
Talk to us for your Gas or Water Meter automation.