roof mounted solar panels - which ones to get?

[shade]

yeah the only way to get lighter is to go for higher efficiency, the bigger those efficiency numbers the smaller the panel is for a given wattage.. and thus lighter.

unfortunately ~20% is about the ceiling for consumer grade panels right now, there's some tech in the 25-30% range but its super expensive and being used more for space applications where cost per pound of reaching orbit is in the 6 figures.

I can't wait to see how @john61ct mounts those on his new trailer.

 

[dreadlocks]

I just went through the first round of interviews at United Launch Alliance, mebe I'll get that job and find something in the rubbish bins out back worth taking home

eh whom I kidding, they aint going to hire me to write code that PREVENTS rockets from exploding.. my forte is the opposite, my code makes things explode.

 

[shade]

I just went through the first round of interviews at United Launch Alliance, mebe I'll get that job and find something in the rubbish bins out back worth taking home

eh whom I kidding, they aint going to hire me to write code that PREVENTS rockets from exploding.. my forte is the opposite, my code makes things explode.

Knowing how to do something well can be a very desirable skill set when trying to prevent the same.

 

[Alloy]

Two hours past sunrise (7:45) there is +\-1 amp under these conditions. View attachment 532205

Cloud cover all day with rain twice.

Peek output was 8amps.

The total output for the day was 23Ah.

 

[67cj5]

Cloud cover all day with rain twice.

Peek output was 8amps.

The total output for the day was 23Ah.

Cool, well that's enough to cover what a fridge uses Ay, and the lesser items will hardly make a dent in what is in the battery,, well done thanks for the info.

 

[dreadlocks]

I was easily getting 100W out of my HIT few weekends ago on complete overcast day, was pretty impressive.. the day before the output hit a full 325W in the sun..

This was Memorial day weekend, I was using ~60AH a day and I only had a ~4-5h of direct sunlight, the rest of the day the panel was shaded by trees.

 

[ken t.]

review Merlin Solar (USA).
4thdsolar is a rep.
I have two of their XP-80 folder.

 

[67cj5]

I was easily getting 100W out of my HIT few weekends ago on complete overcast day, was pretty impressive.. the day before the output hit a full 325W in the sun..

This was Memorial day weekend, I was using ~60AH a day and I only had a ~4-5h of direct sunlight, the rest of the day the panel was shaded by trees.

Dread is that picture from the smart solar APP that you use with the MPPT controllers ??

 

[dreadlocks]

Yup, having stats is extremely helpful in the field.. after the first 24h or so at a site I have a pretty good idea what my energy availability is.. I adjust my usage based upon this.. I can go down to about a 20AH a day diet if power is tight, or if its abundant I can crank it up to 60-80AH a day feast and getta use microwave, crockpots, toasters.. last time I went out I recharged my Dewalt Sawzaw about 6 times chopping wood w/a pruning blade.. didnt even put a dent in it.. ive done that purely off battery before and it hurt how much that sucked out of the bank.

Ive got a 2nd panel here (650W total), Ive done testing with that one in a portable configuration and the amount of usable power I get out of this single LFP battery is friggin nuts honestly.. both combined will charge that thing up in no time, I could fill it up/drain it/fill it up/drain it multiple times in a day if I really wanted too.. I was going to fix it onto the trailer vertically so I could move it when I park the rig in perpetual shade, but the single panel fixed setup has been proving to be more than adequate.. I'mna keep the other panel on back burner for a bit and see if I need it once I get a whole work from camp rig up and going.. with a big monitor, comfy chair, 4g repeater+wifi.. if I dont need it I got plans to put it on a Greenhouse I'll be building soon.

 

[67cj5]

CooooL,

Did you mess with the controllers settings or did you run it as it come in the box, Coz I had a look at it but wasn't sure if I'd do more harm than good, ?

 

[dreadlocks]

yeah I tweaked everything based upon feedback from some of our LFP experts here.. it charges up to 14.4v (96% SOC) to keep the cells balanced, then immediately goes into float (13.3v) which then drains the battery down about 10% and holds it there.. the rest of the day while its in sun its at ~85% SOC, and I use whatever I want during that time.. if I take it down 10%+ w/inverter or something it'll come right back up.. when I go to bed its usually around 70-75%, and if its cold w/alot of furnace usage I'll wake up with 40-50% SOC (also recharging everything w/batteries), I'll use another 10-15% or so making coffee/breakfast and then by noon usually its full again..
It runs full solar even sitting in my yard (during camping season), cuz the fridge is full of condiments and ready to roll at a moments notice.. I'll plug it into shore power every month or so and charge it up with 14.6v, hold it there for a lil bit for a proper cell balancing and to calibrate my battery monitor then unplug it.. over off season I discharge the LFP to ~50% SOC, pull the master disconnect and plug it into shore power.. then I dont really touch it until a few weeks before next season when I'm making preparations.

 

[67cj5]

yeah I tweaked everything based upon feedback from some of our LFP experts here.. it charges up to 14.4v (96% SOC) to keep the cells balanced, then immediately goes into float (13.3v) which then drains the battery down about 10% and holds it there.. the rest of the day while its in sun its at ~85% SOC, and I use whatever I want during that time.. if I take it down 10%+ w/inverter or something it'll come right back up.. when I go to bed its usually around 70-75%, and if its cold w/alot of furnace usage I'll wake up with 40-50% SOC (also recharging everything w/batteries), I'll use another 10-15% or so making coffee/breakfast and then by noon usually its full again..
It runs full solar even sitting in my yard (during camping season), cuz the fridge is full of condiments and ready to roll at a moments notice.. I'll plug it into shore power every month or so and charge it up with 14.6v, hold it there for a lil bit for a proper cell balancing and to calibrate my battery monitor then unplug it.. over off season I discharge the LFP to ~50% SOC, pull the master disconnect and plug it into shore power.. then I dont really touch it until a few weeks before next season when I'm making preparations.

So when I hook mine up to my DC FLA's can I run it as it is or do I have to change things around as 13.8 to 14.5 is meant to be the average ball park figures.

 

[dreadlocks]

you wont wanna use none of that for FLA, its LFP specific.. they will last longer if you dont keep em at 100% all the time.. FLA will croak on yeh if you chronically undercharge it.
If your battery manufacturer gave you charging guidelines, try to set those up.. otherwise, the preset for your battery chemistry should be fine.

I'm trying to get a very long life and a high cycle rate outta this drop in LFP, damn thing was not cheap.. if I kill it, this was a big boondoggle.. but if it lasts, it'll be more than worth it.

 

[67cj5]

Oh right, Well I spoke to the Solar guys about which panel I need but for now I am going to use these FLA's as temporary measure but I want some batteries that will charge up during the limited Sunshine hours I get, I thought about AGB which are 5 X faster than the FLA's but then that brings me to either Lithium or Lead Crystal, either way I need batteries that will charge via solar or a battery charger within 4 or 5 hours, Unlike the FLA's.

 

[calicamper]

My LG 250’s typically run between 160-190watts in full sun. Hot temps impact all panels a good setup has the panel up off the roof some for air flow behind the panel. That alone can be a 30-40% increase in power over a flat mounted panel with no air flow behind it. ?

Mine are on my house. My trailer uses two 10watt panels on 25ft cords I set out. No heavy power needs.