Hello, new to the community. I purchased an AC180 with 1 PV200D panel. Can anybody tell me exactly how fast the AC180 should charge from the PV200D in full sun?
Hello,
If only one solar panel is connected, such as the PV120 or PV200, when the input voltage of the solar panel is less than 30V, the AC180’s PV input voltage will also limit the current to 8A when it is below 30V.
If you have any other questions, feel free to let me know!
I own the newer PV200D as well as the previous generation PV200 model (with blue handle). They essentially operate as an 18V panel in peak Sun. In perfect conditions I will exceed around 160-175W, which is slightly above 8A, but realistically I’m more so around the 125W range, which if you do the math on that is just 6.9A. So two Bluetti PV200s don’t push enough current to exceed 8A anyways, meaning the 30V/8A limitation will never happen. Assume I get 6.5A under peak sun. In series, i will get about 36-38V/6.5A or 235-260W. The highest I ever observed on my Bluetti AC180 when running two PV200s in series was about 260 watts which aligns with what the real world conditions of the PV200 outputs. It’s less than 8A.
Here’s an actual real world sample during peak sun:
I own a PV200D and AC180. Under peak sun I realistically see around 125W during “peak Sun” with maybe a brief 30-60 minute time window when conditions are perfect it goes up to as high as 160-175W. So assume you averaged 100 watts for 5 hours you will realistically be able to recharge at max half of the AC180 in 1 solar day.
Hello, thank you for sharing your details. Judging from the specifications of the solar panel, the highest operating current must be the 8A current limit that can be triggered. The actual charging current of your solar panel does not reach 8A because the solar panel has insufficient energy.
Correct. Keep in mind to reach 8A on the PV200 requires a “perfect world” scenario.
STC parameters are as followed:
- Irradiance @ 1000 W/m²
- Air Mass @ 1.5 which corresponds to solar altitude of 48.2°
- Temperature of solar cells at 25°C
For the PV200D, the panel will not reach a VMP (20.54V) or IMP (9.74A) until it meets these standard test condition parameters above.
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The reality is we can truly only ever control 1 parameter, which is tilting the panel to match the solar altitude of the Sun when the air mass is at 1.5. The irradiance and the temperature is out of our control. Losses are minimal at smaller misaligned values, but are exponentially worse past 15 degrees. So for example if your panel was misaligned both vertically and horizontally would only result in a cost penalty of about 6 or so %.
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For the temperature of the solar cells, every 1 degree above 25C has a cost penalty. Bluetti does not document what the Temperature Coefficient of the PV200 is, but we can assume (based on its construction) its likely around 0.45% loss for every 1°C above 25. A tilted panel in 30°C weather (even with air flow) can easily reach a surface temp of around 60°C. It’s on the ground which radiates heat back. 60-25 is 35. So 0.45X35= 15.75% loss JUST from panel being too hot.
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Assume my panel is 15° misaligned horizontally and the cell temp is 60°C. I would lose 3.41% due to misalignment, and another 15.75% due to hot panel for a total of 19.16% loss or 80.84% power. Since we know the panel produces 9.74A under STC and we calculated in our test scenario we are getting 80.84% of that, then 80.84% OF 9.74 is 7.87A, which is UNDER 8A.
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See what I mean about real life? And this even assumes the sun is 1000 W/m². Light to moderate haze will drop the solar irradiance down to around 700-850 W/m² which is another 15-30% cost penalty. But as you can see, even if the irradiance is perfect, it doesn’t take a lot of miss the 8A requirement. Just a slightly misaligned hot panel will cause it to not produce 8A.
Video sample of my real world test of PV200: https://imgur.com/a/TcRRNCw
-Panel is aligned mostly
-Panel temp is 60C
-There is light to moderate haze in sky in my area currently
Output: 120W max
120/200= 60% real world power
We know 15% of the loss is due to panel temperature as discussed above. This leaves 45% loss remaining due to cabling, misalignment, and haze from wildfire smoke slightly diffusing the light. Since the cabling run is short and the misalignment is marginal, the loss is likely 5% though I can’t know exactly without proper tools. We can apply logic and just assume 5%. This means the haze alone is knocking out 40% of my power!
I have tested the panel several days before in the summer when there was no haze and I reached a peak of 175 watts on the PV200 which corresponds to 87%. Since in the summer the panel reaches between 50-60C due to radiant heat, this number is a perfect reflection of what you would likely get in a real world perfect scenario.
The fact of the matter is most of us who use solar panels are at or near the equator to utilize solar potential which means the panel gets hotter, so 15% loss of power and not only expected, but generally accepted as normal. This is also generally why I hate when solar panel manufactures use STC as the metric to advertise what their panel produces. Heat and horizontal misalignment alone can result in 20% loss.
The panel rating should be based on NOCT which provides a more grounded, realistic expectation of what your panel can typically produce under normal environmental conditions as it factors in heat and irradiance loss. STC is lab driven conditions to list a panel’s rating based on maximum capability. Guess what consumers generally don’t have? A lab.
People see a 200W panel and assume they will get ballpark close to that figure. When the reality is their likely output is somewhat in the 60-70% ballpark. Most consumers (myself included) all learn this harsh lesson when we buy our first solar panels. A solar panel marketed at a larger capacity sells. A lower one does not. It’s all a psychological cognitive bias. You see something at $19.99 instead of $20 and you misappropriate that as cheaper, but the reality is, its just 1 cent!
Hello,
Thank you very much for sharing your detailed analysis and insights! Your deep understanding of the performance and influencing factors of the PV200 is very helpful. Indeed, achieving 8A of current requires meeting a series of “perfect” conditions, and the challenges we face in real-world usage are quite evident.
The impact of temperature and tilt angle on current generation, especially with variations in actual environments, significantly affects the output of solar panels. This information is very important for optimizing usage and improving efficiency.
Thanks again for your contribution!
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In my area, we finally got some relief from the heat so out of curiosity I reran the same test. Look what we have here. Close to 315 watts from two PV200s in series.
AM was at 1.17.
Solar panel temp was at 37C
Both panels were flat on ground.
So the difference between these panels in the same configuration (laid flat on the ground, in series), in roughly 30C weather vs 20C weather is 250 watts vs 315 watts, making heat the most detrimental factor to performance of these portable panels. This makes sense because they are flat on the ground with often times no airflow and close to the ground where radiant heat is the highest.