Can anyone please explain the historical data to me? It looks like my electricity is evaporating.
We seem to have "received" 10602kWh but only "consumed" 8028kWh. What happened to the rest?
asked
Weird historical data
Hi @Paul Carmichael Could you post the other dropdown tabs of the VRM Historical Data for the exact same period?
I can only see the From AC input is 1733KWh, and Solar is 8869KWh, totaling 10602KWh. Your Consumption is 8028KWh, so deducting this gives a net of 2574KWh. I can see you have a battery, due to the blue line on the graph. The net difference would be made up of the battery consumption and solar charging, plus set point settings, and hopefully minor efficiency losses.
I wish I understood. I see a combined "draw" of 10602kWhand consumption of a hell of a lot less. This means I've "lost" 2500kWh, no? So the battery has "eaten" it?
I had also results not looking very reasonable. Try to select "last year" but additionally correct the time settings to "00:00" for start and end time. This procedure shows better results for me.
This is at 0:0
It might not help you find the losses, but your second graph seems to be the more correct one. May be it is a bug or a bit missleading, but "last year" shows not 12 months as expected - it shows 13 month. In your case complete june 22 and not complete (as we are not at the end yet) june 23, which gives big differences showing "last year" at beginning and near the end of a month. In your second graph, you've set the range to the exact 365 days ending with the current date which can make a big difference, especially for the first month.
Your data suggests a loss of around 20%. Victron specifies the maximum efficieny of theyr devices to be approx. 95% - that means it will be less or much less under usual conditions? Depending on the number of devices used (MPPT to battery - battery to grid via Multiplus; PV-Inverter to battery via Multiplus and back to grid etc.) the efficiency losses might sum up. The devices are consuming at least standby power 24 hours. All that might sum up to substancial losses - the energy measurement in the VRM will also not be as precise as with a calibrated energy meter. This is possibly an approximation to explain the difference?
I'm currently assembling the rack for the us3000c collection. These will be a less than a metre from the inverter/muppets. The FLA batteries are in the roof with about 20metres of big fat cabling. Given the vast amount of water that the batteries drink, I'm wondering if that combination may be at fault.
Don't really know your installation but as first analysis I would say that as your average daily consumption is 27kWh, you must have some 9kWc of panels and some 50-60kWh of lead batteries, right ?
- having 48V Lead batteries 20m. away from the point of use is, for sure, a source for some lost by Joules effect
- you are saying you lose a great amount of water, meaning your batteries must be boiling quite often, are you sure about your voltage adjustment and egalization voltage and frequency?
For my part I have LFP batteries and also a consumption of around 20 to 30kWh per day, I don't have a whole year of use but what I can notice is an around 11% lost between production and consumption.
Have 910 ah cells. So prolly 40kWh? But they have never gone below 80%, so mostly wasted. The charging is all Victron defaults. I'm not sure I trust the muppets - for example, yesterday, one was at float and the other bulk. At least the lithium batteries should control their own charging. The FLAs are in a bad way after just 8 years. I can clearly see that in one of them, at least one plate is separated from the bar. And while some batteries look and sound like a boiling kettle, others don't.
@Paul Carmichael
The low DOD is possibly why you have done ok with them.
With FLAs there is quite a bit of maintenance that needs to be done. Not just referring to electrolyte top up.
8 years is s decent run, at this point blaming a product is a bit below the belt. Calendar aging is also a thing on batteries. Was there bank rotation? Do you have any kind of cell balancing on the bank? Plate separation on an FLA is more than just a charging problem.
Looking after lead acid batteries is quite an art.
Whoa. I don't think I was blaming anything. I think it's pretty much accepted that Muppets don't play well together. It's been the same from day one. There's always been a massive imbalance, even though the panels are balanced. Just considering the possibility that that has something to do with it. The worst of all is the "installer" was quite openly practising on me and didn't have a clue what he was doing. I now know a lot more than he does about this stuff. Anyway, we'll see how we get on with the new batteries :-)
Sorry but there is NO victron default values for battery voltages, this is a mistake that could explain some of the misbehaviour.
Values for batteries should be adjusted according battery values as provided by battery manufacturer
They should re-write the manuals.
@Paul Carmichael
FLAs take power to float. So even on float charge they would be drawing amps. Hence the high losses. The losses get greater with age as well.
Then there is charge efficiency of the batteries as well. 80AH out means at least 100AH to replace as an example.
And Victron do recommend using the battery manufacturer specs for charging since they cannot cater for all the batteries in the world. Battery profiles are all editable.
20% is also explainable to some extent with power factor and wiring and heat losses on top of battery losses. To be honest 80% is pretty decent with your system setup and use.
