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Choosing between Bluetti's PV350 and PV200 solar panels for a Bluetti AC300 system

Joe Murphy

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I am completely new to the world of solar generators. I am in the process of buying a Bluetti AC300 solar power station (which is rated at 3kW). The system can accommodate from one to four B300 batteries, with each battery having a capacity of 3kWh.

The AC300 has dual MPPT controllers (solar inputs), with each controller being rated as follows: 1200W max, Voc 12-150V, 12A max.

Bluetti offers two types of solar panel that would seem to be usable here, and I am trying to decide which of the two to go for, with the main consideration being to max out the amount of solar input:

  • PV350 (Pm = 350W, Voc = 46.5V, Isc = 10.8A, Vmp = 37.5V, Imp = 9.2A)
  • PV200 (Pm = 200W, Voc = 26.1V, Isc = 10.3A, Vmp = 20.5V, Imp = 9.7A)

PV350: If, for each MPPT controller, I used 3 x PV350 in series, this would give a combined output of 1050W max, being only 150W short of the max 1200W that can be handled. It would also give a combined Voc of 139.5 (46.5 x 3). My main question: Is 139.5V too close to the max allowable input voltage of 150V, considering that the Voc value can apparently increase in cold weather, and so apparently you need to allow some bit of a buffer?

PV200: Otoh, if I instead used PV200, I would be limited to a quantity of 5 in series for each MPPT controller in order to stay below the max input voltage allowed, being 150V. So, with 5 x PV200, this would give a combined output of only 1000W max, being 200W short of the max 1200W that can be handled. It would also give a combined Voc of 130.5 (26.1 x 5), which gives a slightly larger clearance from the 150V max allowable, compared with using 3 x PV350 units.

Another thought: an advantage of using PV350 units might be in having fewer panels and fewer connections to have to manage.

Any thoughts would be welcome.
 
I am completely new to the world of solar generators. I am in the process of buying a Bluetti AC300 solar power station (which is rated at 3kW). The system can accommodate from one to four B300 batteries, with each battery having a capacity of 3kWh.

The AC300 has dual MPPT controllers (solar inputs), with each controller being rated as follows: 1200W max, Voc 12-150V, 12A max.

Bluetti offers two types of solar panel that would seem to be usable here, and I am trying to decide which of the two to go for, with the main consideration being to max out the amount of solar input:

  • PV350 (Pm = 350W, Voc = 46.5V, Isc = 10.8A, Vmp = 37.5V, Imp = 9.2A)
  • PV200 (Pm = 200W, Voc = 26.1V, Isc = 10.3A, Vmp = 20.5V, Imp = 9.7A)

PV350: If, for each MPPT controller, I used 3 x PV350 in series, this would give a combined output of 1050W max, being only 150W short of the max 1200W that can be handled. It would also give a combined Voc of 139.5 (46.5 x 3). My main question: Is 139.5V too close to the max allowable input voltage of 150V, considering that the Voc value can apparently increase in cold weather, and so apparently you need to allow some bit of a buffer?

PV200: Otoh, if I instead used PV200, I would be limited to a quantity of 5 in series for each MPPT controller in order to stay below the max input voltage allowed, being 150V. So, with 5 x PV200, this would give a combined output of only 1000W max, being 200W short of the max 1200W that can be handled. It would also give a combined Voc of 130.5 (26.1 x 5), which gives a slightly larger clearance from the 150V max allowable, compared with using 3 x PV350 units.

Another thought: an advantage of using PV350 units might be in having fewer panels and fewer connections to have to manage.

Any thoughts would be welcome.
If you have cold temps where you are located I wouldn't push it that close to the 150v input.
Are you set on purchasing an off the shelf system or would you consider DIY? I ask because I looked up the price of the PV350 and I'm still shocked, I paid ~$65 for a single 315w panel...
 
As above those are expensive panels which unless you need the portability with the saving on storage space more traditional panels would generally be cheaper and better spec. Also be very careful, the max voltage is not a guide but a hard maximum figure. Go over it and you could cause permanent damage.
 
I have three Bluetti units the AC200P, EP500Pro and the EB55, if you go over the voltage you will get an overvolt error that you will just have to clear. I believe the EP500Pro uses the same controllers as the AC300.

Is there a reason why you need the portable solar panels? as mentioned above it would be far more economical to go with traditional solar panels. I have used three 285w totaling 855w (I would have to look at the isolator but I think the total VOC is around 110v) traditional panels on both the AC200P and EP500Pro and they work fine.
 
Thanks to everyone for your replies. I live in Ireland, which has a fairly moderate climate, so that it hardly ever goes below minus 3 deg C (27 deg F). The downside is that we don’t get that much direct sunlight.

It's peculiar that Bluetti don't specify temperature coefficients for their solar panels.

I’m thinking of going with Bluetti panels since I want portable panels and ones that are easy to store away. I don’t plan to use them on a daily or weekly basis.

@solarpowa, It's good to know that Bluetti uses over-voltage protection.
 
I would recommend building your own versus going with the Bluetti. I do like that the AC300 allows 2400 watts of solar input, whereas the AC200 only allows 900 watts. I believe that you should be able to have enough solar input to not pull from the battery when running your max average loads, which for me is 1800 watts for an Air Conditioner.

If Bluettie won't publish specs for its panels, that's another reason to get your own All in one, MPPT/Inverter and panels that will publish these specs. Especially when this will be used in a place that will get cold out.

I know someone mentioned clearing the overvolt error, but for me each time that error comes up, there is potential damage that could be done if this does not kick in quick enough. I'd feel more comfortable with a design that has more of a buffer and I know the tolerances.
 
They have some temp info under general here https://bluettipower.co.uk/products/bluetti-pv350-350w-solar-panel

"GENERAL
Connector:
Standard MC4 Connector
Weight:
30.6lbs (13.9kg)
Dimension (Unfolded):
35.6 × 94.4inch (90.5*240cm)
Dimension (folded):
35.6 × 24.1 ×2.5in (90.5*61.3*6.5cm)
Operating Temperature:
14-149℉ (-10-65℃)
Best Working Tmeperature:
77℉ (25℃)
14-149℉ (-10-65℃):
118in/ (3m)
Warranty:
24 Months (Enter to learn more about BLUETTI warranty policy)"

That price though for one panel ouch.

The AC200P only allows 700w solar input the AC200Max allows 900w, the AC200Max can also be expanded with 2x B230 or 2x B300 but there is a workaround for the AC200P. The EP500Pro gives you up to 2.4kw of solar also same as the AC300 but its 5kw on wheels instead of stack and can support 2x B230 or 2x B300. There is an older AC200 that also supports 700w solar input but I think it is not lifpo4 and only has 1.7kw battery but can use the workaround to add more storage.

One thing to note about the B300 battery compared to the EP500Pro is the B300 is rated at 3500+ cycles to 80% but the EP500Pro is rated at 6000+ cycles to 80%.

B300 := https://bluettipower.co.uk/products/b300?variant=43138240872614
EP500Pro := https://bluettipower.co.uk/products/bluetti-ep500pro-5100wh-3000w-power-station

I agree about the overvolt its a nice feature but you probably don't want to rely on it, just in case.
 
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