Hi guys/gals…complete noob here, just purchased a PS54 on the cheap from BLUETTI ebay, Ive got a 100w Renogy PV and obviously a car output…Initially i wanted to charge the PS with the car AND solar, but learnt that is not possible with the DC7909 input (apparently it just regulated to the AC charger brick only) so the DC7909 to XT60 i purchased is useless 
So then thought, perhaps if i bought a XT60 female to a 2 male XT60 splitter that that may work (98w car/100w solar) again, no dice
so then considered a 12v to 24v (8A) convertor and apparently that wont work either, this is what i was told “I want to tell you that the solar panel cannot be directly connected, and another module needs to be added to stabilize the voltage. You must confirm this first.
Our boosters do not increase power. Your cigarette lighter is 12V 8A 96W, so if you use this as an input power supply, the output can only be 96W, and there is no more.
If you need 200W of output power, the input terminal needs to use 12V input voltage and the output needs 200W to convert it into 24V 200W output.
Because the total power of the input and output remains unchanged, you need to reach a maximum of 200W, and the input terminal must be able to match it.”
Is there a cheaper way of converting the (I.e not the charge 1 or its ilk) 12v 8a 96w to 24v 8a 200w (ish)
Any help would be most appreciated.
See