WHY do all-in-one Solar Power Inverters have a high idle consumption? Asking to learn...

It's time I upgrade my entire system. I loved Will Prowse's video on the MPP all in one system he built, and I'm interested in spending a few thousand dollars to upgrade everything. The most unexpected CON of the All-in-One systems are the "high idle consumption" rate. Somewhere around 1.2kW per day!...That's an entire 12V 100aH battery. Seems really really high, so I'm looking for an explanation of why that is. Maybe I'm not thinking on the right track, but at that point, I'll have to buy 400 more watts of solar and another 12V battery, upwards of $1500 ADDITIONAL? Thanks.

That works out to 50W which is pretty low for most Inverters.
Some Inverters especially the Low Frequency kind can be real power hogs going up to 100+ watts of power and some High Frequency ones are still power hungry using 90W. The reason is that the circuitry inside is always powered on and also powering multiple power conversion systems, like DC to AC for the batteries to be stepped up to line voltage, DC-DC for the charging of batteries from PV power and AC-DC for using the Grid to charge the batteries along with PV DC voltage to AC for direct solar powering. All of these systems need to be ready to go in case any one of them Sags or drops out the others can be used to keep the output AC voltage steady.

In some inverters it is just a case of a bad design but in other inverters it's really just a case of how many multiple cirucits are energized. Each only takes a little power but it adds up.

Victron Multiplus are not AIO. But have the lowest idle draw specs of most any inverter out there for the size, by far. Then there are 2 more programable settings to set them even lower.

Depending on your use case, an all-in-one may not be the best choice. Yes, a 50W load will use 1.2kWh/day - as you say, a full 12V 100Ah battery.

If you don't need an inverter on all day or better yet, every day, then consider getting an inverter/charger and a separate solar charge controller instead of an all-in-one. My 24V/2000W Victron MultiPlus uses 15W at idle. And when I don't need the inverter (which is most of the time) I can turn it off and have no idle consumption.

ValleyViewer said:

I'll have to buy 400 more watts of solar and another 12V battery, upwards of $1500 ADDITIONAL?

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What do you plan to buy that is so expensive? A quality 12V 100Ah battery can be had for under $600. A cheap one is under $400. And you can get a new, high quality, 400W solar panel for under $300. Buy panels locally to avoid shipping.

ValleyViewer said:

It's time I upgrade my entire system. I loved Will Prowse's video on the MPP all in one system he built, and I'm interested in spending a few thousand dollars to upgrade everything. The most unexpected CON of the All-in-One systems are the "high idle consumption" rate. Somewhere around 1.2kW per day!...That's an entire 12V 100aH battery. Seems really really high, so I'm looking for an explanation of why that is. Maybe I'm not thinking on the right track, but at that point, I'll have to buy 400 more watts of solar and another 12V battery, upwards of $1500 ADDITIONAL? Thanks.

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What is the application as this is 12V? If RV, then you can always add a remote switch to turn off the inverter when you aren't using it. It will still charge the batteries when PV is sufficient.

For a dwelling, 12V isn't optimal, even a small cabin.

rmaddy said:

Depending on your use case, an all-in-one may not be the best choice. Yes, a 50W load will use 1.2kWh/day - as you say, a full 12V 100Ah battery.

What do you plan to buy that is so expensive? A quality 12V 100Ah battery can be had for under $600. A cheap one is under $400. And you can get a new, high quality, 400W solar panel for under $300. Buy panels locally to avoid shipping.

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Sometimes it's not a matter of just the cost of the battery and extra paneling... In many cases there's a physical limitation of space to mount that extra equipment.

not sure i see the problem here..

given todays cheap panels and batteries, how the heck is 50 watts a problem ?
a more efficient inverter may use less power , but in general the pricing ( in some cases tripple ) would quite easily be negated.

a 250w solar panel can be had for 50usd...

If you live in a sunny climate it's not big deal. Where I live, my 20kw of panels will produce 1-2 kWh of power on many days in the winter. An inverter that draws 1-1.5 kWh of power is using up a good chunk of my day's production.

Bvillebob said:

If you live in a sunny climate it's not big deal. Where I live, my 20kw of panels will produce 1-2 kWh of power on many days in the winter. An inverter that draws 1-1.5 kWh of power is using up a good chunk of my day's production.

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You must be living near the North Pole? I have 10Kwp of panels and it has to be a day with dark low lying clouds and rain before my output drop to 400-500W. With 20Kw of panels that would be 1Kw.

That power is not a total loss. I mean it is powering the inverter, and a good small source of heat if you seal up and insulate your power electronics and batteries in a room. Although you can get batteries that operate at all sorts of temperatures, they last much longer if you control the temperature more tightly - at least in my experience.

robby said:

You must be living near the North Pole? I have 10Kwp of panels and it has to be a day with dark low lying clouds and rain before my output drop to 400-500W. With 20Kw of panels that would be 1Kw.

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I have 300w of panels on my driveway lights and they can't produce 120Wh/day every day from about Oct to March in Western, WA. Rain and clouds kill me. The 50w doesn't sound like anything, but after 24 hours that's 1200wh, or a full 100Ah 12v LFP battery just to exist. In my neck of the woods that would require about 3.5Kw of panel through winter just for the AIO to be on. Requiring 50+w of draw to come out of standby mode means adding higher loads (I'd have to turn on every light in my cabin AND something else to achieve that) which means more batteries and more panels and so on.

It adds up fast in some places.

Don't know about the all in one units but the stand alone units vary. I have a 4000 watt 110 Giendel that idles at 4 watts but I have a 5000 watt Sigineer 110/220 volt that idles at 40 watts.

GLC said:

I have a 4000 watt 110 Giendel that idles at 4 watts

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Link please? Is that in standby mode or something? What's the wattage draw to wake it up?

My pair of MPP 3048LV MK's in split phase consume 34-38 watts each. My underlying load thru the night (tv standby, network gear, microwave clock etc) is about 200 watts. Daytime with lights 2 computers, TV's, fridge, mini fridge, freezer, etc is about 900 watts.
If you are going to run inverter 24/7...
Just plan for it. Its one of your loads.
35 watts of standby for 4 discreet devices inside that all in one is, in my opinion, nothing to get all twisted up about.

Also try to take into you plan that if you have base loads that cant be turned off (like @TomC4306 said), then your idle consumption in irrelevant, since the inverter isn't at idle technically. If you have a constant 200w load, then technically you are not at idle, and now it all depends on inverter efficiency.

This is how I try to look at it anyways. But if you have very little base loads, like less than 50w, then yes the idle consumption is relevant to your calculations.

If it makes anyone feel better, my Skybox has a 300 Watt consumption. I don't worry about it because the erosion of benefits of Met Metering have been more costly. Because solar panel are cheap, I am just going to add more panels. I understand that does not answer the OP's question, but it is what it is. It is still better than paying over $0.50 per kWh to PG&E.

Rednecktek said:

Link please? Is that in standby mode or something? What's the wattage draw to wake it up?

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Here is the unit. I have 2 of them. When you turn it on it uses between 2.5 and 4 watts with no load. I have a video of it I will try to post.

GLC said:

Here is the unit. I have 2 of them. At stand by it uses between 2.5 and 4 watts. I have a video of it I will try to post.

Amazon.com

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Well, it wont let me post a video off of my phone.

GLC said:

Here is the unit. I have 2 of them. When you turn it on it uses between 2.5 and 4 watts with no load. I have a video of it I will try to post.

Amazon.com

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Huh, is that when it's switched off or something? According to the link it's got a 36w standby draw.

• No load current: 1.5Amps

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Still, nice inverter.

Rednecktek said:

Huh, is that when it's switched off or something? According to the link it's got a 36w standby draw.



Still, nice inverter.

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After having my Magnum Ms-pae 4448 for a while, I can say that I am totally impressed with the idle current and efficiency it has. In Maine we have plenty of days without sun and the batteries have never discharged to the point of the inverter totally shutting down. I think the ide current is way less than 1 watt. The Overkill Solar BMS does not even measure a current draw when the Inverter is in idle mode and waiting for an AC demand. The only drawback that I can see is that they are on backorder and are very difficult to find some dealer who even has one on the shelf. And if you do happen by on then expect to pay over $2k for it. I have only been using it for a bit over 3 months but it has been working better than I have expected and it is made in the USA. From everything that I have read about them they are rock solid and will last a very long time. I use ours to power the whole house including a microwave, washer dryer, two freezer and a fridge and everything else in our 2k square foot house. It is a beast.

When I look at the power produced by the solar panels and then look at the energy that we used from CMP, it looks to me like almost all of the panel energy is being used by the batteries/Inverter and not much is lost. An example is that we have generated an average of 19kw per day so far this month and have used from CMP about 5.5 kw per day. Our normal useage for this month was 27kw per day before we added the panels and Inverter. I could not be happier with the results of the Magnum Inverter.