How can a 38.4Ah NCM Li-ion battery run down from 100% to 47% overnight when the Yarbo isn’t doing anything? I understand it is doing things like GPS and HaLow communications, but otherwise there is no reason for power to draw down. This is not new. From day 1, if I don’t charge it for 2 days, it is completely dead and needs to be plugged in before I can even get the thing to start up.
My phone does that same things (GPS and network connectivity), plus bluetooth, NFC, power a screen, run dozens of apps in the background, and actually process data, has a battery of 4685 mAh (4.68 Ah) and it doesn’t get below 50% in a full day of use.
If you calculate how much power that really is to a homeowner, 19 Ah recharging at 120 volts is 2.3kWh. My rate is $0.095 per kWh, or around $6.50 a month, just for the unit to sit there and do nothing (like it has done for the last 30 days, waiting for snow).
I realize that $6.50 doesn’t sound like much, but for a device that should be drawing nearly ZERO, it matters. I use the same amount of energy to mow my lawn each time it runs. How can it use the same amount of energy doing 5 hours of mowing as sitting for 12 hours doing nothing?
I’ve been doing a Shutdown from the App if I know I’m not going to be using it for a week or more. If a software update is released, I’ll power it on and make sure it’s charging but I have been keeping it powered off. The battery still says 100% after being powered off for nearly a week.
Recently I’ve added simple power meter on the socket for the dock. And also was quite surprised about power usage when yarbo is just sitting on the dock with 100% charge and “battery care active”. Have not calculated exact numbers etc, but I was expecting something close to nothing
Remember that it’s still a computer and a bunch of radios and receivers. The dock supplies power to keep all that running even when not actively charging the battery.
120V is what the charger runs on, but is not the battery voltage. That would be 36V.
19Ah is the battery capacity not a constant rate that the battery draws.
A full charge of the battery is equivalent to drawing 19A for 1 hour at 36V, which is 0.7kWh which would cost you about $0.065 to fully charge the battery one time. If you were to assume you had to do that every two days, that would total about $0.97. AND THAT’S ASSUMING YOU’RE FULLY CHARGING IT EVERY TWO DAYS. Never mind that the charging pad or wired charger is going to be drawing some small amount of power on its own when it’s sitting idle, or that the data center is probably drawing more power when its idle. And technically, if you leave the rover on charge when you’re not using then the battery should be staying fully charged and the only power being drawn is whatever it takes to keep the electronics alive.
To my knowledge, if the rover is ON it’s basically running at full power all the time so that it is ready to run whenever you call for it. The lights, cameras, and some of the sensors may turn off, but the main computer stays up. Unless you actually power the unit off by holding the power button. I did this with my unit while I was waiting for the Pro Mower to arrive and over the course of a month the battery only dropped about 2%. When you stop using your phone, the display turns off, it slows down how often if at all it updates GPS, most apps get stopped, etc. If you want a true side by side comparison keep your phone active with google maps up on a split screen while you stream spotify. See how long your phone’s battery lasts then.
Ok. So it’s been about 12 hours since I started the power logging, so here are some preliminary results. For context, I am in Michigan, and the temperatures dipped below freezing last night. So I’m assuming Yarbo’s heaters kicked on as a result.
Total electricity used : 0.544kWh
Total electricity cost : $0.081
Idle watts used : ~11.3 watts
Peak watts used : ~120 watts (when heating?)
It will be interesting to see if these preliminary results extend through entire 24 hour periods. My guess is the power utilization will go down during the daytime due to less heating. I’ll update the thread again tonight.
So far, the extrapolated results aren’t bad at all. Under $5.00 a month in electricity during cold weather months.
Ok. So it’s been about 12 hours since I started the power logging, so here are some preliminary results. For context, I am in Michigan, and the temperatures dipped below freezing last night. So I’m assuming Yarbo’s heaters kicked on as a result.
Total electricity used : 0.544kWh
Total electricity cost : $0.081
Idle watts used : ~11.3 watts (Yarbo sleeping)
Idle watts used : ~13 watts (Yarbo awake via app)
Peak watts used : ~120 watts (when heating?)
It will be interesting to see if these preliminary results extend through entire 24 hour periods. My guess is the power utilization will go down during the daytime due to less heating. I’ll update the thread again tonight.
So far, the extrapolated results aren’t bad at all. Under $5.00 a month in electricity during cold weather months.
Sleeping versus awake? Ya, for like a little mini computer or micro ATX system, that sounds about right if they aren’t putting it in some sort of dedicated special low power sleep mode…. which I doubt they are doing given its responsiveness. But ya, 7-15 watts sounds like any of those little desktop mini PCs.
And 120W when heating sounds about right too depending on the temperature they’re trying to maintain and the outside ambient. Remember that soldering irons are 40W-80W but are highly concentrated in where the heat is generated. Heck, your average hair dryer uses upwards of 1200 watts on average.
Another good example for the battery heater is those little desktop fridges the sell for keeping a couple of soda cans cold are peltier coolers and usually run in the 50-100 watt range.
No, this was a good discussion. I don’t think anyone had ever analyzed the power utilization before. Always good to have actual data.
To be honest, I was kinda worried the utilization would be higher. My test is still ongoing. Let’s see what happens after an entire day, just to be sure.
Mildly concerning considering we average ~$0.27/kWh here… I get why it would have to run camera heaters when “near freezing” or if there is precipitation. I wonder if the connection to the weather API could be utilized in the future. Li-ion batteries will have reduced power output when below freezing but should generate their own heat as they’re being used. As long as the core and BMS can account for that having a cold charged battery at the start should be fine as long as it takes it easy until warmed up. As long as it either uses power from the wireless charger to heat the battery before charging and/or warms up running the workplan that should be fine. If the weather looks bad it could prompt the user to enable “full power mode” and keep everything heated for optimal performance.
Ok. So it’s been 24 hours, and here are the results…
Total power consumption: 1.032 kWh
Total cost (based on $0.15 per kWh): $0.154
Extrapolated monthly cost: $4.62
Keep in mind, this is with Yarbo idle, sitting on the dock in chilly-to-cold Michigan weather. Looking at the graph, I see 3 spikes in power utilization which are likely the heaters, with amperage peaking at 159.3 watts. Idle wattage averaged to about 11.12 watts.
So all in all, Yarbo isn’t the most energy efficient device out there, but it’s not going to break the bank.
So today I checked what is the number there.
It’s 9.6 kWh in one week. And according to the work plan history, Yarbo has consumed around 135% of battery on work plans during the week.
So as i’m actually paying 0.24 EUR per 1 kWh, it’s 2.30 EUR for that week.
(0.24 EUR = 0.28 USD)
Average outside temperature this week was something around 1 - 2 degrees celsius (~ 33 F)
I’m a data driven kind of guy, so I have multiple ways to monitor such things.
I installed a whole house energy monitoring system that is installed in the breaker panel. It monitors and tracks power utilization from every circuit, plus the combined totals. Really nice way to see what things are consuming the most power, and how to optimize your home’s efficiency.
But in this case, Yarbo is connected to a circuit with other stuff on it, so the data wouldn’t be accurate. So I just ended up using a plug in electricity monitor and watched the data roll in.
So Yarbo is basically on a “kill a watt” usage meter?
What system did you put in your house? I’d be interested in the details on that if you dont mind sharing?
