We’ve wanted to have near-realtime water consumption data for our irrigation for a while. The stumbling block was never the cost of adding the meter. We just don’t have any spare wires from the house to where the submeter would be to supply power or collect pulses, so the answer was always going to be wireless with some sort of long-term independent power supply. There’s a ton of this sort of thing that works over radio and sends data to a base station, which then sends it on to a collator (usually requiring a subscription), but the data is more along the lines of billing or gross leak consumption info, and we’re fairly subscription-averse. I’ve found a few that worked over wifi and could report data via UDP for local consumption, but they were $200+, and once you set the reporting interval anywhere below hourly, battery life was ~1 month.
I periodically do a web search for this sort of thing, and Google reliably takes me to a bunch of sites for commerical or near-commercial products that don’t meet our needs. But about a month ago, I stumbled across this:
He has his firmware code on Github, so it’s modifiable. His default reporting interval is daily, but the battery life impact of changing that is a drop of 10% or so…from 4 years down to 3.6…using 3 AAs. He shipped me two completed devices, along with batteries and programmer tools, for $60 US, which arrived last weekend. I’ve cloned his code and am changing the prompts to English and will be changing the reporting/wakeup interval, and then loading a device up and hopefully not bricking it. Am now (finally) shopping for cheap 1" submeters with pulse output, so we can segregate data from the two halves of the yard. I may pay the guy we have do large irrigation jobs to put them in…there’s nothing hard about it, but the lines are deep, and I am old.
Anyway, thought this might be of interest here, as data nerds abound. His prompts make it clear that his expected use is within a home or apartment, allowing separate metering for hot and cold water. But he’s been very helpful trying to get me to my use case. And BTW, the devices are a bit smaller than a normal pack of cards, with 3 AAs onboard.