Portable Power Station Solar Input Limitations - Workaround?

Question

I'm considering buying this unit for backup energy + solar charging:

https://www.ecoflow.com/us/delta-pro-portable-power-station

Now, the max input is 1600W with 150V and 15A max. This is acceptable if the sun shines bright and I'm getting the 1600W into the system. However, that is obviously not always the case. You need to overdesign your solar array to get an average of 1600W into your system due to cloud overage etc... Thus, my problem is I cannot connect 150V, 30A setup to the device as it could potentially blow a fuse or not be compatible.

Is there anything that can be done upfront to accept higher amps, and discard anything above 15A? So that I only feed 15A into the power station? Throw away any excess energy? Maybe put a Victron solar charge controller and feed that into the power bank? I know this is a long shot, just asking if something like this is possible?

Answer 1

I found the user manual.

Unfortunately there's not much interesting stuff in there.

Since the battery is 48V and the solar panel voltage can rise up to 150V, there's probably a DC-DC converter in there to charge the battery, with charge current regulation.

Normally, if the product is sane, the 15A specification should mean the maximum current it will draw from the solar panels. So it should be possible to use panels capable of more current, and if there is a lot of sun, it would simply max out at 15A and take whatever power it can.

If it was a solar battery charger, well the simple ones just connect the panels to the battery, which have to be the same voltage. If these products are badly designed (ie, no monitoring of overcurrent), sure, they can fry if the solar panels are too powerful. But this one supports a wide voltage range, so it probably doesn't use such a simple circuit.

However, the documentation gives no details. It doesn't even say if it has an MPPT. I guess you'll have to ask the manufacturer.

Personally I'd get another brand with proper documentation.

Answer 2

The only thing you can do is use a separate current limiter to put in front of the unit. Units like that exist, but are unusual and expensive and hard to find. It's not a realistic option for ordinary users.

Or you can connect up more panels, and sit and watch to be sure it doesn't get up to 15A. That's also not a realistic option for ordinary users.

The current limit on units like this is pretty much a hard limit. If it could handle 20A in, they'd call it a 20A unit. Sometimes the unit can handle a '15A' panel that is new, and cold, and runs at 16.5A, (You can ask the supplier about that) and sometimes you may find a 15A unit de-rated to '13.5A' for special purposes, but it's never going to be 20A for a 15A unit.

Answer 3

Your palel voltage in must remain below 150 V at all times. I will be overpaneling my unit with 2P2S 49 Volt 460W panels. 98 Volts x 16 A (actual limit on ECO DP is slightly higher than 15A from what I've researched) will give me a little under1600 Watts. The 1840 Watt panels will just give me a slight boost in harvesting efficiency. The ECO DP limits current for the different voltages that it can accept. It's not a resistor. It's an active inverter. Temperature can affect your solar panel output voltage. Never run near the 150 limit.