ok hear me out. I have an AC180 and two cheap flexible 100w solar panels (OCV 21v, 5A). I have been getting very poor performance from these panels. When I first got them I could squeeze out about 140 watts total running them in series. Now nothing above 90watts combined. Cheap panels, what can you do. So I recently bought a Renogy 200w folding solar panel ( 23vOCV, 10A) ( haven’t received it yet). Thought I will just use that instead. However, much to my chagrin I recently read on these forums that the AC180 limits input amps to 8A when it is receiving 12-36 volts, only delivers full 10 above 36 volts. This really ticks me off. What is the purpose of this Bluetti? So this new panel will never ever get above 160 watts in reality ( max, so less with conditions). Stupid! So I thought to push the amps to max why not use my other two 100w panels to increase the volts. Can’t run them all in series cause that would just nudge me over the voltage limit of 60 of the bluetti. I read that you can over amp the Ac180 no problem. So if I push 20 amps to it , it will only use 10. No problem. So my question is this. Can I run my 2 100w in series then run that into a parallel connector and then run my 200w on it’s own into the parallel connector and then into the bluetti? In theory the amps will combine up to 20 Amps as one side will be a total of 10 amps and so will the other. But the voltages would be very mismatched. One side would be combined about 40 ish give or take and the other side 23v. If it only ups the amps to the full 10a at the bluetti that would be helpfull even if it doesn’t give me the full 400watts. I at least want to max out my new panel at the full 10 amps, which it will not do on it’s own as it is 23v and the bluetti will not take in the full 10 amps below 36v. Sorry for the long post but detail was needed. So is this possible? I understand that I wouldn’t be getting the full 400watts total due to mismatched voltage in paralell but it should at least be better than running my new 200w at a down rated 8amps ( thanks again bluetti, bad design)
The AC180, I have one, has a solar input range of 12 to 60VDC at 10A max and 500W. If you multiply VxA=W then theoretically 60V x 10A = 600W. However, the specs say you must limit the voltage to no more than 60V. This means that 3 nominal 12V panels that have a Voc of over 20V will exceed the 60V limit.
So, if you are limited to 2 panels in series, your Voc will be around 42 to 48V depending on panel. A 200W panel typically has an output of just over 10A, so 2 in series with a max Voc of 48V will give 480W, which is near the max 500 Watts input… more next post
Your new Renogy has a Voc of 23V at 10A. Your flexible cheapies have a Voc of 21V @ 5A. The math if you connect the 2 5A in parallel, then connect that string to the Renogy in series is;
23V+21Vx10A = 440W maximum. But, if your cheap panels are not hitting 21Voc or dropping their Vmp under load, then it will affect the total output, dragging the Renogy down due to lower voltage. To the point, the Renogy may well be better by itself. I’m using 2 x 150W HardKorr solar matts (already owned them before buying the AC180). On a good day I get over 280W from them in series. They’re not cheap, but the old saying applies, “You get what you pay for”. :) Hope this helps.
Great reply @Mandp…@Damann, If I were you I would follow the advice connecting the panels given by Mandp and see what you get. They will either work well or they won’t and you will be able to tell if you have panel damage or degradation by connecting them and seeing what you get.
Yup, thanks guys. Only way to know for sure is to try it. If it drags the renogy down then I will just use it on it’s own. Any idea why they would design the Bluetti to only limit to 8A when below 36v? Doesn’t make a lot of sense and most people with a 200w panel are never ever going to see the 10a output of the panel. I’m going camping in a few weeks. I will try it out and report back my findings. Thanks for the replies!
I doubt it is a “limit”. i.e. I do know that the Victron MPPT controllers will not start charging until solar V is 5V or greater than battery volts. Using AGM at a state of charge of 50 to 75% and under some load, the battery will be at approx 12.2V, which means solar V need to be around 17.2+. However lithium batteries will still be 13.1 to 13.2, which means solar needs to be higher at 18.2 or greater. For a MPPT with an input range voltage of 48V (12-60) I would imagine the greater the voltage, the more efficient they are.
Although a nominal 12V panels Voc is around 22V and will work with the smaller Bluetti PB, connecting 2 in series will always get you more charge.
To explain, 1 panel first thing in the morning may only produce 14-15V and therefore is not working. 2 panels in series at the same V will be at 28-30V and although not producing much, will still be trickling something into the battery. Same thing occurs, later in the day. :)
DeMann - Here’s a little test you can do. Try it on a reasonable sun day, middle of the day, with the AC180 at or lower than 50% SOC. Look for a stable W input figure on the 180 during testing.
- Connect your cheap panels in parallel, plug into the AC180 and note the input W = W1
- Unplug those panels and plug in the Renogy, again note the W = W2
- Connect the paralleled cheapies in series with the Renogy then plug all into the 180 and again note W = W3.
In theory W1+W2 should = W3. If W3 is lower than this calculation, that is how much the cheapies are dragging down the Renogy. If that is the case, when convenient, get a second Renogy and take the cheapies out of the equation.
Perfect. Was thinking about this on the weekend and was going to do just that. Going camping in the next couple of weeks and i will try it and report back. Thanks for your suggestion!
ok I managed to do some testing over the weekend with full sun and just some slightly whispy clouds around. Temps 14c. So pretty ideal conditions. Findings were interesting.
So with my renogy 200w folding panel I got a max of 156w. My two old 100w crappy flexible panels in series alone got 35watts! In parallel those two 100w panels got 65w. They are both clearly damaged and finished. So when I combined the two 100w panels in parallel and then added them in series to the 200w good panel I got the exact same output, 156w. So it is as if it discarded the two flexible panels completely. Which is fine, they are clearly not functioning well.
But what I did find out was that the 200w panel got a max output of 156w on the AC180 but when I put that same panel into my older EB150 power station I got 178w! So clearly the other reviewer was correct in that the AC180 will NOT give you the full 10amp solar input if the panel is below 32volts. This to me is completely unacceptable. In fact it is false advertising. No 200w folding panel on the market will ever achieve a theoretical max output of 200w from a 200w panel unless it is over 32v. To my knowledge there is no folding 200w panel on the market that runs above 32volts. Not even bluetti’s own 200w folding panel will do this. So, in my eyes it is false advertising and this absolutely has to be addressed. There is no reason why the solar input of the AC180 should be limited to 8 amps below32v. You lose 20% of your power. Surely this can be addressed with a firmware upgrade. If it does not I will be looking for a refund.
The way I look at this is; The AC180 will accept 500W or more, providing the Voc is below 60V. Therefore anything bigger than approx 250W is going to be a large panel and difficult to go camping with, which means to achieve the 500W, 2 panels in series is required. That Bluetti do not state that at below 32V the unit is limited to 10A is not false advertising. What they do state is that the unit’s DC input is limited to 10A, solar is DC, however at close to 60V x 10A = 600W and that again is not false advertising. As I mentioned, a good quality 200W panel will have a Voc of around 22-24V and slightly more than 10A output max. The math of 2 in series is 44-48 x 10 = 440-480W, again in perfect conditions. I’ve just returned from a trip and will post my observations next post.
My setup this trip - Caravan (or trailer if in the U.S.) 2 x 100Ah LiFePo4 house bats, 160W on roof panel and 2 x 150W HardKorr Crockskin solar mats angled on the ground. It’s autumn here and on clear skies, I got 26A input to the 200Ah, had used 52Ah overnight and the solar stopped charging when at 100% around 1330hrs. Gotta be happy with that. My solar controller is limited to 50V so the 3 panels have to be in parallel. I do have a series patch lead, but only use that with the 2 x 150W as I isolate the on roof if camped in the shade. Next - how I charged the Bluetti AC70 & AC180…
I took the AC70 & 180 on this trip, their primary use - The 180 for the caravan as I no longer carry a petrol genny. I use it for the microwave and other 240VAC appliances, toaster, small electric kettle, toasted sandwich maker and electric toothbrush. It weighs 16kg, not that heave, but not to move every day and it sits on a board on a spare seat in the van. The AC70 sits next to it and in the evening after the AC180 is no longer used, I charge the 180 from the 70.
Next morning, I put the AC70 in the 4x4, strap it down and connect it to the Victron 375W inverter I installed. When driving it charges from the 4x4 on silent mode at 280+W and generally I don’t use more than that from the 180. I still have the option to plug it into the 300W of H/K panels in series after the van is charged if not travelling. The AC70 at 9.5kg is much easier to pick up and travel with, plus if I want, I can take the kettle and toasty maker on a drive to make lunch.
Everyone has different needs, equipment and processes, I post this to give you and others ideas for use options. 
Bottom line, both units are doing everything I ask and I’m happy with this setup. (I was away 8 days, including one day of heavy overcast. I idled the 4x4 for 2 hours using the DC-DC to supplement the solar on the caravan.)
Thank you for your positive contributions and feedback. Portable power stations do require a moderate amount of electrical knowledge in order to obtain the highest satisfaction from their use.
Happy to comment. One needs to step back and ask, is an item doing what is stated? Do I understand how and why it works? Am I using it properly? Given that a Power bank replaces, Battery, Inverter, DC converters (Bat V to 12 & 5V) Solar Controller, AC charger, Battery management System and Battery Monitoring System all wrapped in one device, a degree of elec knowledge is still required. I’ve designed and built systems the old fashioned way, which need a lot more Real Estate and messy cabling to connect it all with fusing to protect it. I know when I’m better off, lol. The other plus - Installing all of the above in a 4x4 is usually a permanent install, or effort to remove it, a Bluetti is pick up, relocate, reuse and it’s as much process as technical.