Would Will do an update to his 400 watt RV solar DYI build?

Back in the early days Will had a publication with several suggested build layouts including one for, as I recall, a 400 watt solar set up for RV. Solar, and in particular RV solar systems have become increasingly popular over the years and solar technology has become exponentially more sophisticated. I looked today for Will's original post from several years ago, and apparently it has been moved or taken down. Would he consider providing an update? Fore example , may on youtube build systems at 1.2kw to 3k watts of panels and as many as 2kA of battery storage. I would like to know if his original 400 watt system is still valid or if he would change anything genve current technology.

Still there...https://www.mobile-solarpower.com/

Glad to know it is still there. Having re-read it, I am still curious, given the advances in solar technology and LiFePO4 batteries, and the reductions per watt of power and storage, would Will revise the advice or change it any way?

I can’t speak for WProwse but in my mind’s eye it’s still relevant.

I assume 400W solar panels which works good for 40A SCC, ~200Ah of 12V lithium battery/batteries and ~1200W pure sine inverter.
Another option in virtually the same cost range is an MPP Solar 1012LV-MS and 600W of panels. Simpler and has the advantages of grid input with automatic transfer switch and a built in 50A battery charger. I have the -MK version and if I were to do what you’re asking about I’d go this way as first choice. If running a smaller 120V electric fridge that is adequate, but more dependable would be 300-400Ah of battery storage and 800W of solar.

12VoltInstalls said:

I can’t speak for WProwse but in my mind’s eye it’s still relevant.

I assume 400W solar panels which works good for 40A SCC, ~200Ah of 12V lithium battery/batteries and ~1200W pure sine inverter.

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100% agree - I use a similarly-sized system in my trailer to run mostly DC loads (lights, fridge, laptop, fan) with occasional 2000W inverter use for 1500W kitchen appliances and it works great.

So as an example, assuming a 12v fridge one might be better off with a 400 Amp server rack as opposed to 4 -100 amp 12v LFP ad perhaps 2 or 3 larg ( 300w+) panels as opposed to 8 - 100w solar panels.

Not sure I understand your comment, but I think 12voltinstalls was referring to the total PV input, not the size of the individual panels. For info for your system planning, I run a 24V 206 Ah system (2 x SOK 12V) with 400W panels, 12/24V Dometic fridge, 12/24V USB-C laptop/phone chargers, 12/24V lights, and a buck converter feeding 12V to my MaxxAire fan and cellular router.

If you can post more details regarding the needs of the system you are interested in building you could probably get some more specific input.

280Ah feeds my Element bargsin fridge just fine on sunny days when my inverter doesn’t cut out. It’s minimal imho- it will go ~1.67 cloudy days if it gets a good charge. I want 2 days with headroom.

1holaguy said:

assuming a 12v fridge

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For the cost of a real 12V fridge that’s not worth it to me dollars-wise. And those refrigerated coolers are clunky, small, and use up floor space. My ~7.5CF top freezer model cost me $215 and the leftover cash can buy a lot of panels if you needed to.

1holaguy said:

one might be better off with a 400 Amp server rack as opposed to 4 -100 amp 12v LFP

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Yes. And no. Redundancy and “buying in” to scale up over time is an advantage with smaller batteries. Even two 200Ah could be a good choice.

1holaguy said:

ad perhaps 2 or 3 larg ( 300w+) panels as opposed to 8 - 100w solar panels.

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If you have the space. Yes.

I’m running either 8 or 10 100W panels and will be adding six 330W panels I sourced NOS for ~$800 total last fall. Those six 330W cost about the same as eight of the 100W panels did.