Harvesting Solar

[Cptnvideo]

Please see signature for list of equipment installed and in use.

We are currently sitting for 2 weeks in a RV Park in Goodyear, AZ with included electric. I was curious about just how much solar power I could harvest for a mostly sunny day in February. So I unplugged after breakfast and while the solar charger was still in bulk charge mode. I don't recall exactly, but I think we were at about 96% SOC or down about 40 ah. While unplugged, electric water was on and DW did 2 loads of laundry, plus 20cf res fridge, microwave, TV etc were consuming battery/solar power.

Solar charger stayed in bulk charge all day and finished 5 ah shy of full charge. The Victron SmartSolar app showed the panels provided 4.97 kwh of energy for the day with a max of 1014 watts. Based on a reference of 13.5 VDC, that is 368 ah that could go to the batteries if no loads were present.

Unfortunately, that is not enough energy to permit us to boondock strictly off solar for more than a few days at this time of year.

[StirCrazy]

Cptnvideo wrote:
StirCrazy, solar and batteries are kind of like fun, mayo and butter & sour cream - there's no such thing as too much. 🙂 🙂

I kinda look at it the same way, but my wallet will argue with you 🙂

[Cptnvideo]

We're currently camping near Bouse, AZ on BLM land. Our Victron solar controller app showed a solar harvest of 7.57 kwh yesterday. Had to cycle the electric water heater to maximize harvest. Typical TV, lights, res fridge, microwave and LP furnace blower loads.

[Cptnvideo]

StirCrazy, solar and batteries are kind of like fun, mayo and butter & sour cream - there's no such thing as too much. 🙂 🙂

[StirCrazy]

Cptnvideo wrote:
StirCrazy, I understand about the bar fridge, but there are other advantages to upgrading solar and batteries. We started out with 1200 watts solar and 618 ah of LFPs. Then added 400 more watts, then I added 2 more LFPs. I'm about maxxed out, not much room on the roof for more solar and adding more would require a controller upgrade.

oh ya definatly, I have three 180 watt 12V panels on the fith with a PWM controler and four 6V batteries so a usable 200ish AH. when I do that upgrade I am going to switch to three 350ish watt 24V panels MPPT controler and then Ill put about 900AH of LFP in there. I figure that battery capacity will give me about a 9-10 day reserve at my current usage, or once I start running the bar fridge that could drop down to a 3-4 day reserve if the solar ***** out. the increase in solar should put me up to around 60 amps or more of charging for the good 4 or 5 hours so thats more than enough to charge and run the bar fridge through the day. I do have the advantage of not needing my AC and a lot of the 120V stuff in normal situations. I carry two coffee pots a perculator and a kieurg, a regual toaster and a camp stove toaster and so on so if we are having issues with power it isn't a hardship to reduce my power usage.

[Cptnvideo]

StirCrazy, I understand about the bar fridge, but there are other advantages to upgrading solar and batteries. We started out with 1200 watts solar and 618 ah of LFPs. Then added 400 more watts, then I added 2 more LFPs. I'm about maxxed out, not much room on the roof for more solar and adding more would require a controller upgrade.
2 nights ago, I forgot to plug back in. We were watching TV with the fireplace and 2 space heaters running (we hate to be cold). When the water heater apparently kicked on, the inverter shut down. "Oh ****, I forgot to plug back in." By the time I plugged in and reset the inverter, we had drawn 764ah from the batteries. Remained plugged in yesterday, and the solar remained in bulk charge all day and put 5.54 kwh back into the batteries. Sunny all day, so that is the max I can expect from my solar in mid Feb in AZ. BTW, we still aren't fully charged, SOC is up to 78% (cloudy day isn't helping either).
With regard to the fridge draw, I noticed about a 4 amp draw on the batteries this morning with no lights on (and plugged in), so the fridge might not be drawing as much as I thought. So my evening draw is something like 4 amps misc, 4 to 5 for lights and TV, and 5 to 11 amps for the fridge.

[StirCrazy]

Cptnvideo wrote:
StirCrazy, our fridge is a 20cf residential and total hourly battery usage runs between 16 and 20 ah. So for 24 hours, draw on the battery bank is between 384 and 480 ah. We have and can run A/C as well.
Our intent was to boondock about 75% of the time but it has turned out to be more like 50%. Like 2oldman said, we wanted comfort and convenience. And like Vintage 465, our boondock limitation is water - we need water every 9 or 10 days. With a reasonable amount of sunshine we can boondock indefinitely without a generator (although we do have one). That does exclude December when the sun angle is too low and not enough hours of sunshine.

ya I guess comfort and conveniance is different for everyone, I was just surprised at the draw total.. it is incomprehensible for some one who lives up north and boon docks. the only people I know that put residential fridges in are snowbirds that go to Arazona for the winter 😉 like my mom and dad haha..

for myself I have 480 watts of solar and four 6V GC batteries in a 40 foot 5th, we use 110 in the morning to make coffee and toast, then in the evening for the kids to watch a movie, maybe the microwave to warm up leftovers for supper, make popcorn, or if the youngest grandsone is with us to warm up baby food/bottles. and of course to run the keuig to make coffee. other than that I have a insiir panel so I only turn on my inverter when we are going to use it, the water heater, fridge and BBQ run off my propane, I take my GMG smoker but it only draws 40 watts of 12v for 2 min then goes down to 10watts for the rest of the cook. by myself with a full take of water I could probably go 2 to 3 weeks, with the wife up to 2 weeks, if we got the kids we are down to a week watching the water.. and my batteries are back up to 100% every day.

I did try run the electric bar fridge in the outdoor kitchen but its draw is just to much to keep up with so my next project will be to increase the solar enough to cover that also and switch the 5th to LiFePO4 like I did the camper. I don't need the bar fridge but I like that I can pack it plum full with pop and beer and not worry about having it in the indoor fridge. I guess you could put an adsorbition fridge in there... thats something to look at but I think it would be cheeper money wise to upgrade my solar and batteries.

[Cptnvideo]

Ivylog, I am neither bragging or complaining - just sharing some observations.
You obviously read the first post since you mentioned the 2 loads of laundry, but your comprehension isn't very good since I also said I had been plugged in at a RV Park but unplugged and intentionally drew down the batteries to see how much solar I could harvest in February in Arizona.
Also, my numbers are NOT way off. The numbers are directly from my Victron SmartBMV monitor. And I never said it was all fridge - the 16 to 20 amps is the total hourly draw with the fridge having most of that draw.

I also don't understand your logic of cranking up the generator for the washer/dryer if the solar and batteries can handle it. You said it was a waste of battery usage. I say I'm utilizing solar and battery and NOT wasting gas running a generator.

[Ivylog]

Not sure if you’re complaining or bragging. 2 loads of laundry assuming dry too is a waste of battery usage… crank your generator. Your refrigerator #s are way off, even with the ice maker on. My 21 Whirlpool draws 8 amps measured before the inverter and only runs 40% of the time… confirmed with a KW meter at 1.3KW/day with the ice maker off.
When using a high amp item for any length of time, crank the generator and turn the ice maker on to harvest the ice. With no one near you, what’s with not running the generator?

[Cptnvideo]

I forgot to mention - our 5th wheel came with a RV fridge, but we couldn't keep it in the 30-40° range and 3 different RV techs couldn't find any issues. So we replaced it with the 20cf Whirlpool that we purchased at Home Depot. So solar/battery demand was a little more than we originally anticipated.

[Cptnvideo]

StirCrazy, our fridge is a 20cf residential and total hourly battery usage runs between 16 and 20 ah. So for 24 hours, draw on the battery bank is between 384 and 480 ah. We have and can run A/C as well.
Our intent was to boondock about 75% of the time but it has turned out to be more like 50%. Like 2oldman said, we wanted comfort and convenience. And like Vintage 465, our boondock limitation is water - we need water every 9 or 10 days. With a reasonable amount of sunshine we can boondock indefinitely without a generator (although we do have one). That does exclude December when the sun angle is too low and not enough hours of sunshine.

[2oldman]

Vintage465 wrote:
Normally, if one wants to boon dock for any real length of time you not only set your coach of with a robust solar, you fit the coach with appliances that minimize the use of 12v power

I maximized my coach with use of 120v power with lots of solar, big inverter and Li battery. Some folks like conservation, I like comfort and convenience.

[Vintage465]

Cptnvideo wrote:
Please see signature for list of equipment installed and in use.

We are currently sitting for 2 weeks in a RV Park in Goodyear, AZ with included electric. I was curious about just how much solar power I could harvest for a mostly sunny day in February. So I unplugged after breakfast and while the solar charger was still in bulk charge mode. I don't recall exactly, but I think we were at about 96% SOC or down about 40 ah. While unplugged, electric water was on and DW did 2 loads of laundry, plus 20cf res fridge, microwave, TV etc were consuming battery/solar power.

Solar charger stayed in bulk charge all day and finished 5 ah shy of full charge. The Victron SmartSolar app showed the panels provided 4.97 kwh of energy for the day with a max of 1014 watts. Based on a reference of 13.5 VDC, that is 368 ah that could go to the batteries if no loads were present.

Unfortunately, that is not enough energy to permit us to boondock strictly off solar for more than a few days at this time of year.

I'm not sure where you're going with this other than "information". Normally, if one wants to boon dock for any real length of time you not only set your coach of with a robust solar, you fit the coach with appliances that minimize the use of 12v power Surely with the loads you have boon docking for any amount of thime will take more power or less load. We have a totally different set up than you. 450w of solar, four 6v Golf Cart batteries, absorption fridge and zero 120v appliances, so no inverter. And obviously since we have such a small draw we can go weeks at a time off our solar and battery bank.....but we will run out of water with in 2 weeks........and ironically the holding tanks are about full when we run out of water:S

[StirCrazy]

Cptnvideo wrote:

Itinerant, we also do LP water heater when boondocking. Our killer is the fridge. At night, with a couple LED lights on, TV, & fridge, the draw is 18-20 amps. That puts us in the 460-480 ah neighborhood for 24 hours. Add in a little more for microwave, furnace blower this time of year.......

Are you running AC also? I cant seeing the fridge running 24/7 it has to have a cycle. I would hazard to guess about 50% cycle when its real hot out.. but I could be wrong.. 460 to 480 just seams like a lot for just a fridge tv and lights.

man and I thought I was an energy hog at 60-90AH per day (depening if I am running the furnace or not) in the 5th wheel 😉

Steve

[2oldman]

Cptnvideo wrote:
2oldman, no, they don't tilt. Hence why I only got 1014 watts from 1600 watts of panels, then there is also shading from the A/C units, etc.

Yeah, I guess with 1600w you really don't need to. Still, 1014 from 1600 is pretty good. I tilt when I'm facing west (which seems hard to find) simply because it's so much easier with my configuration and I don't get the a/c shade.