Solar recharge time

[Kelly]

We are planning to boondock at Fish Creek Ponds in NY.  This is a beautiful campground!  We tent camped here last year and loved it, and now plan to use our new to us Ollie "Rita".  We are looking at October, so will not need AC.  I think the only things we would need elec for would be lights at night and the water pump.  We can use our camp stove or the propane cook top indoors for meals.  The sites are all partial shade.  So, if I am planning a 5 day/night trip, do I need to get a portable solar panel that I can direct towards the sun (as opposed to the rooftop panel that may be in the shade).  My son tells me that solar recharge is extremely slow, if so, should I get a portable honda generator.  Or maybe I do not even need to worry about it.  Any tips/info would be appreciated.  BTW, I know nothing about solar power.  

[Kelly]

Camp stove outdoors of course.

 

[routlaw]

You haven't stated what sort of batteries you have and how many amp hours of storage you have within those batteries. In general LiFePO4 will charge at a much faster rate than wet cell lead acid or AGM's. However given you're minimum usage of electricity its unlikely you would need a generator.

We have been using our Oliver for over 7 years, with 4 Trojan T-105 wet cell batteries which has 450 amp hours of storage, however only 225 ± of those amp hours can be used without damaging the battery bank. With lithium you can use almost 100% of their storage and safely down to 15%. We do not carry a generator and have never needed one either. Typically we will only use 2-3% of our battery storage per day which is easily recharged by mid morning in the summer months out west. If you are in shaded areas it might take a bit longer. Also if you access the furnace with cooler nights this will draw about 3 amps per hour from your battery bank and this IS by far the largest amp draw, assuming you don't try to use the AC.

Cutting to the chase I wouldn't worry about it much if at all. Still you need to know and understand not just your solar capabilities but also you battery bank capabilities. Hope this helps.

[SeaDawg]

Hi, Kelly, and congratulations on getting your Oliver. Do you have an Elite I or II? Which batteries do you have, as that will help us estimate your available amp hours. As tent campers, you're used to managing without power, im sure.

Not only will the tree cover reduce your charging ability, especially if the leaves are still up, but the hours of sun are less in the fall. You'd probably still be fine, if you don't have to run the furnace much at night. 

We've camped up that way in October, though never Fish Pond, and got some rainy cold weather. 

 

[John E Davies]

Kelly, at this stage in your RV life you need to educate yourself. There is an awful lot of technical details about solar, but the basics are not hard to understand. The more you read, or watch videos, the more you will learn. The learning curve is quite steep at first, but it makes sense after a while

https://www.imnotlostimrving.com/rv-solar-system-overview/

Northern latitude, known tree cover, short days, possible foul weather. You need a small generator without a doubt! Solar does best in high summer out in the open. Even if you never run your air conditioning off the generator, one day, for sure, you will need it to recharge your batteries. 

John Davies

Spokane WA

 

[CnC]

Simply said...  Your son is correct.  There are so many variables involved that simple answers are not easy.  Maybe this will help - we use about 100 to 120 amp hours in 24 hours of boondocking.  Our solar on top of the Ollie can collect up to 340 watts (that equates to less than 6 amps per 100 watts per hour in direct, full sun).   As you can quickly see 6x3.4= 20.4 amps an hour just isn't going to replenish the battery usage each day.  Starting out with a full lithium battery bank of 300 amp hours in our Ollie, we can go about 5 days in the best of circumstances (direct, full sun.)

Charlie. 

[SeaDawg]

We have dry camped most of the time with our Oliver Elite.  But, we camp (like you)  as if we're in  a hard sided tent. 

Experience will help. We carry a little Honda 1000 just for charging batteries. We also have portable solar, but only use it if we're at a site for many days.

Unless you drive an suv, and don't want to carry a generator in the cabin, I'd opt for the small generator "insurance policy. " easy to carry and deploy.

I'll add this. I have a good friend with a Casita, single group 27 battery, can camp 2 to 3 days or so without power, in decent weather - in the fall, in treed north carolina, and upstate new york. She is also a veteran tent camper. 

We camp the same way, but we have an electric dc compressor fridge. Fall is much more problematic than spring,  because just the fridge uses 60 to 70 ah a day. So, we can't go 5 days in full  shade, in the fall, even with 400 watts fixed solar. That's not your situation,  since you can run your fridge on gas. Your fridge takes gas and minimal power.

You do need to monitor amp hour consumption.  And replenishment. 

Everyone is different in their style and needs.

 

[routlaw]

1 hour ago, CnC said:

Simply said...  Your son is correct.  There are so many variables involved that simple answers are not easy.  Maybe this will help - we use about 100 to 120 amp hours in 24 hours of boondocking.  Our solar on top of the Ollie can collect up to 340 watts (that equates to less than 6 amps per 100 watts per hour in direct, full sun).   As you can quickly see 6x3.4= 20.4 amps an hour just isn't going to replenish the battery usage each day.  Starting out with a full lithium battery bank of 300 amp hours in our Ollie, we can go about 5 days in the best of circumstances (direct, full sun.)

Charlie. 

Wow! 100-120 amp hours per day, may I ask what you use this much power on. In seven years we have never ever come close to this much energy consumption. Not being derogatory just curious. Typically we only use about 9-10 amp hours per day unless we need to use the furnace then it might jump up to 20-40 amps at the most. I can only recall once that our battery bank did not fully recharge in a day, with the exception of our last trip where the solar controller the Blue Sky was not operating properly. 

In any case if the OP is only using the water pump and lights it highly unlikely they will burn through more than 10 or so amps per day, unless of course they have to rely on the furnace which will change things quickly.

[MobileJoy]

From a ticket I opened last year (Jason):

"The 340w solar panel system can generate up to 18.8a per hour but that is under perfect conditions which would be sunny day, no cloud coverage at high noon in the south. Between sunrise and about 10am this will be much lower but you should see it increase as the sun continues higher but will start to decrease around 2pm once the sun starts it descent. Under real world conditions you can expect on sunny days depending on your location and time of year to be anywhere between 50ah - 125ah. The farther north the less high sun exposure there is for the panels."

The 18.8a number comes from Zamp. Here's a link to the solar panel:

https://www.zampsolar.com/collections/roof-mount-kits/products/170-watt-long-expansion-kit

In my brief experience with them, I have seen a maximum of 120ah collected in a combination of being on the road and at a campground one recent day in NC with a clear sky all day and full exposure in both places. It would probably be somewhat better at the summer solstice with clear weather.

I have the Lithium Pro package.

 

 

 

[Steph and Dud B]

Really interested to discover how we make out up here in CT. One of our favorite dry-camping spots is full-sun, basically a field near the ocean, so we're hoping we do well with solar there. Other sites are often partial- or full-shade but we're hoping we can manage mid-week stays if we start with the 630aH Platinum bank fully charged. We also have a fall weekend in mid-state NY with full-sun. For now we're going to bring our little Honda genny with us all the time, at least until we get a feel for the solar performance under these conditions.

In a couple of years we'll finally be able to go back to "sunny day, no cloud coverage at high noon in the south." 🤠

[Steph and Dud B]

@Kelly please post photos of your trip to Fish Creek if you can. Looks like a great place. We enjoy NY state parks, too!

[routlaw]

55 minutes ago, Steph and Dud B said:

Really interested to discover how we make out up here in CT. One of our favorite dry-camping spots is full-sun, basically a field near the ocean, so we're hoping we do well with solar there. Other sites are often partial- or full-shade but we're hoping we can manage mid-week stays if we start with the 630aH Platinum bank fully charged. We also have a fall weekend in mid-state NY with full-sun. For now we're going to bring our little Honda genny with us all the time, at least until we get a feel for the solar performance under these conditions.

In a couple of years we'll finally be able to go back to "sunny day, no cloud coverage at high noon in the south." 🤠

If you have 630 AH of Lithium battery storage I can't for the life of me imagine you would ever need a generator to supplement your electrical needs. Again we only have 450 AH in our 7 year old wet cell lead acids batteries which effectively only means 225 AH without theoretically damaging the batteries. We live above the 45th parallel and not once have we ever needed a generator, and this is camping from the first week of March through about mid Oct. To the best of my recollection the lowest our charge ever became was around 83-84% capacity due to cold weather and running the furnace far more than normal. 

Given our minimalist style of camping a 100 AH Lithium would probably work for us, based upon past history of electrical usage. However I will most likely do a 200 ± AH battery bank of Lithium once we make the change over. As the saying goes YMMV. 

[CnC]

Well, there you go Kelly.  You have a camper using DC and a glamper using AC relating real life experiences.  Only you can decide the amount of AC/DC usage which pleases your lifestyle.

Charlie

 

 

[Liana]

18 hours ago, SeaDawg said:

You do need to monitor amp hour consumption.  And replenishment. 

Now that I have the 300Ah of BBs installed, I know how to monitor replenishment, but I'm still not clear how to monitor usage.  Someone above mentioned that the furnace draws 3a/hour, that is hugely helpful to know and it made me wonder where I find (or how to calculate?) the draws that various components use.

EG, we are dry camping and have a completely overcast day with cold enough temps that I need the furnace on while I'm on the computer.  I can see that the solar is providing a little over 3Ah at its lowest, has gotten up to 9 earlier with a bit of filtered sun (and I know that my panels are not sparkling clean).  It's supposed to snow here tonight and freezing temps, so I'm anticipating needing the furnace all day and night (thermostat is at 62, so it's not running *that* much)

I have a generator I can use if need be, I also have an additional portable solar panel but it's so windy here today that setting it out will probably not go well for the solar panel (fabricating a frame that can be anchored is a project for another day...). 😄

Zamp 30a charge controller so we all know what I have.  Near as I can tell, the ability to determine the SOC with this controller is fairly coarse, am I understanding that correctly?  ie, I think it is the four little battery icons under the words "battery condition" PLUS the LCD status indicator.  I think that means that the SOC is *somewhere between 50 and 75% when the 3/4 battery icon LED is on plus 2 bars solid, 2 flashing on the LCD status.

What's my threshold for breaking out the generator (Honda 2200) and if I can break out the manual as well, what information do I need to be able to figure out how long I should run it?

[Steph and Dud B]

12 minutes ago, Liana said:

I know how to monitor replenishment, but I'm still not clear how to monitor usage.

Our ambulances have a little digital meter that shows +/- amps. Let's us easily see if we charging or discharging and by how much. I think others have installed something similar in their Ollies. Hopefully, one of them will pipe in with the details.

[CnC]

We use a Victron shunt and Victron battery monitor that displays on an app all DC power coming into and out of the batteries.  That way you can watch as you turn on or turn off separate things and their usage.

Charlie

 

[Liana]

31 minutes ago, CnC said:

That way you can watch as you turn on or turn off separate things and their usage.

Which is cool, but not having such coolness, I might have to manually tally (calculate?) components' usage?  eg, I look at the specs on each to figure out how many amps it will draw?

[routlaw]

3 hours ago, Liana said:

Which is cool, but not having such coolness, I might have to manually tally (calculate?) components' usage?  eg, I look at the specs on each to figure out how many amps it will draw?

Exactly this is how I came up with the almost 3 amps for the furnace draw. Its actually 2.7 according to the specs. The Blue Sky solar controller and its associated IPN Remote provides a lot of calculated information but not being familiar with the Zamp have no idea how it compares. 

[ScubaRx]

On 5/20/2022 at 3:42 PM, routlaw said:

… but not being familiar with the Zamp have no idea how it compares…

Poorly, but the 2023 models have all Victron equipment. This is a game changer. 

[Kelly]

On 5/20/2022 at 10:57 AM, Steph and Dud B said:

@Kelly please post photos of your trip to Fish Creek if you can. Looks like a great place. We enjoy NY state parks, too!

I will!!  I usually post pictures on the oliver trailer owners on facebook.  We tent camped at FCP last September, chilly, but thats the way we like it!!  Sites are all right on the water, so we brought our kayaks and was able to put in right from our sight.  Tupper lake and Saranac Lake are both close by for supplies and treats.  

[Kelly]

4 minutes ago, Kelly said:

I will!!  I usually post pictures on the oliver trailer owners on facebook.  We tent camped at FCP last September, chilly, but thats the way we like it!!  Sites are all right on the water, so we brought our kayaks and was able to put in right from our sight.  Tupper lake and Saranac Lake are both close by for supplies and treats.  

 

[Steph and Dud B]

Beautiful!

[topgun2]

Wow!  

At first glance I thought that you had started a fire in the bed of your pickup.

Nice, warm shot.

Bill