1 or 2 solar panels??

[NEWYORKHILLBILLY]

I have a 19 on order I debating weather to have EFT install 1 or 2 solar panels , the new panels our 160 Watt . Of course i will get the 2 6 volts batteries. I will do lots of boondocking ,But maybe one panel would be plenty?

[TZBrown]

It really depends on your power usage and how much sun you can get.
On our previous TT we had 320W and unless we parked in the shade could not lower the voltage below 12V after 10 days, but we are pretty low usage. did run the TV all we wanted though.

We are going with just one, 160 panel on the Escape 21, but I do have the previous panels for portable power if we stay in one spot for a longer time. If we went with 2 we could not get the TV antenna

[padlin]

It's up to your proposed camping style.

I don't do any extended boondocking, a couple nights here and there, seems I have hookups more often then not, not that I search them out. We also don't use much power. If I was parked in the dark I could go roughly 10 days in the non heating season without the need to recharge, about 10 amps a day. In the winter we use closer to 20 amps a day, so I could go 5 or 6 days in the dark. I carry portable panels as well as the 160 on the roof, I've yet to need the portables. I've also yet to see the panel on the roof not put the batteries back to 100% during the day. We recharge our phones, use the lights, water pump, and whatever the fridge uses when it's on propane.

Other folks use much more power then we do, having an inverter to run a juicer, microwave, fridge, coffee maker, or whatever. For them a 2nd or even 3rd panel may be the best route.

If you are handy you can add panels later if you find the need.

Having the extra panel really hurts nothing other then the wallet, no extra maintenance other then they get in the way when washing the roof.

A Portable may be a good route if you want to be able to stay out for a week up north during deer season or some such. Flat mounts on the roof are of limited use when the sun is low in the sky.

[fudge_brownie]

I think Bob describes it well. Another variable is, if you consistently stay and for long periods in campgrounds with limited sunlight the rooftop mounts may not reach the sun. A portable panel may be a solution.

I think of National Parks in the west as quite shaded, ususally without shore power and often visited for many days. Portable may be a solution.

Our family are power hogs, with all the charging, medical device, inverter and vacuum cleaner we can easily use 25 amps in a 24 hour period. Your experience will vary but Bob gives some good numbers.

[jrb1947]

We bought our 21 without solar. Boondocked at Davis Lake in the Cascade Mountains in September. Cold nights. Major power draw was furnace and charging computers and cameras. Battery lasted four days. Still had water and tank capacity. Had ETI retrofit one solar panel. That should keep battery happy until tanks are full. Will know when we are at Quartzite in January.

[Losangeles]

not to start a debate about towing with propane on, but... we prefer to have the fridge on 12v when towing, (not propane) so that pretty much makes 2 solar panels a necessity.

and

ETI reenforces the roof under where the 2nd panel goes if purchased at build, (hidden wooden blocking) and you cant really add that after build, (unless you cut open the ceiling fabric, i assume) so i liked the sound of that - having #2 solar panel added at build.

we like to do long boondocks, and also year round, so low sun + shorter days = 2nd solar panel.

we like to be active during our boondocking, so prefer to be out hiking and exploring, so worrying about a solar panel getting stolen, or readjusting it as the sun shifts = not for us.

yes a portable one gives more shade flexibility, and we already own one, so we had a ZAMP inlet port and wiring all done by ETI at build.... but i didnt want to NEED to do a portable.... ever... so dual 6v + dual ETI installed roof solar panels = easy and worry free



john

[thiggins]

We like to camp in the shade, and aren't huge boon-dockers so far, so we're going totally portable solar on our 21 build, no solar panels on the roof. I just sent a Zamp connector pigtail to ETI to install for us. We are in the southeast where it gets hot, so we seek shade ASAP. I also want as few holes as possible in the shell.

[BCnomad]

OP, many excellent responses especially by Bob and JRB.

My only suggestion is that I have read winter use can be approximately three times as much as summer use. So in other words, if 50 W of solar will work in the summer you need about 150 in the winter for the same amount. Remembering that furnace use will be battery drain.

You might want to do an energy audit to find out how much the online calculators think you need in terms of wattage. Someone can post a link if you ask.

Personally I do not have solar but wish that I had so I could stay out longer without any battery anxiety. It will greatly depend on where you are and when you are.


The other side of the coin is that you could upgrade the batteries instead for increasing your time between plugging in. Depending on circumstances of course.

[steve dunham]

We have one 27F deep cycle battery and one 100 watt portable solar panel . In the 5 Years we have owned our solar have we gotten down past 50% of battery charge only once and that was on the 4th day of a 4 day camping trip. We do not continually monitor our usage .

[Greg A]

We use approx 7-10 ah per day. With the twin 6v we can use approx 110ah before having to put back in. Thats over 10days before any charging is needed. With the 160 panel we’ve never had any need past that and boondock about half the time including some shade and rain days as well. This is based on our daily usage and these results will erode if using the furnace constantly.
The most efficient option would be the one roof panel with a solar portable for the winter or shade situations. The drop in the winter angles can be eliminated with a portable that can be set up to match the sun angle. With the 19 and the external access to the batteries a port wouldn’t be absolutely necessary as you can clip the portable straight to the battery terminals if you want to and it has an onboard controller.

[ksitte]

Originally Posted by NEWYORKHILLBILLY

I have a 19 on order I debating weather to have EFT install 1 or 2 solar panels , the new panels our 160 Watt . Of course i will get the 2 6 volts batteries. I will do lots of boondocking ,But maybe one panel would be plenty?

I notice you have a 19' on order. I wasn't aware that ETI would install 2 panels on a 19'. Is that now the case?

[Mark James]

No easy answer here it depends on electrical usage and how long between charges. On the trailer I just use the one panel for the two batteries. On my power boat I use 2 while at anchor to top up 4 large golf cart batteries. Generally I find I have good power for at least 5 nights out. One thing you might want to consider is adding in a 2000 watt portable generator into the mix. I run two Honda 2000 generators wired in parallel for topping up batteries and running AC when boondocking. Works well. Hope this helps. Solar even gives me some juice on a largely cloudy day,

[h2owmn]

Thanks for the timely information, all. I'm having to make the decision about solar asap. My max boondock is likely about 4 days. The convenience of the roof mount is tempting, but I'm a shade seeker for landing spot, so I'm thinking portable would be better for me in terms of use. I'm hearing that the two 6 volts are better for this than a 29..is that right?

[Rossue]

Would definitely get the dual 6V. We started out with a Group 29 12V with 160W panel and worked well, however you really need somewhere to store the energy you are collecting. We switched to dual 6V after a year. The dual 6V are 232 amp hours, whereas the Group 29 is not even rated by Interstate, however probably around 85- 90 says Interstate rep(ETI says 95). Nowadays, you must get the dual 6V if you get factory solar.

[sclifrickson]

Originally Posted by ksitte

I notice you have a 19' on order. I wasn't aware that ETI would install 2 panels on a 19'. Is that now the case?

Yes.

[rbryan4]

I don't need a 2nd panel, and it wasn't really an option when I had our 19 built. Having said that, knowing what I know now, I would much rather have a 2nd panel instead of that Jack antenna.

[alanmalk]

Originally Posted by NEWYORKHILLBILLY

I have a 19 on order I debating weather to have EFT install 1 or 2 solar panels , the new panels our 160 Watt . Of course i will get the 2 6 volts batteries. I will do lots of boondocking ,But maybe one panel would be plenty?

I would agree with others who have said that a portable panel, in addition to the single ETI roof panel, is a good solution.

I have found that in the summer the single roof panel is sufficient. But for fall and early spring I measured the output from my 150 watt portable to be double that of the roof panel. The portable has the advantage of being pointed in the optimum direction for maximum output, whereas the roof panel is always flat and just can't produce anything close to summertime power.

Plus a portable gives you the option of parking your trailer in the shade on hot days while deploying the portable out in the sun.

Of course a compromise might be to have ETI prepare the trailer for a second panel and you try some fall/spring camping and see what your actual needs are. In other words, push the decision out until you have your own personal data.

--
Alan

[gbaglo]

Keeping in mind that two solar panels are twice as noisy as one.

[Rossue]

"Silence is golden". When rolling through a campground for a site we check to see if neighbors have generators and avoid them if possible.

[Losangeles]

Originally Posted by steve dunham

I own , use , and like solar !!
My question is and it is academic.
" At what point does the cost of solar panels , extra / more
batteries , an inverter , the additional wiring , maintenance and replacement exceed the cost of just buying a generator ?
I am not advocating for generators but I can buy a really nice generator for around a $1000 plus the generator can run my A/C.

Fair question... i guess it all depends on style of camping

we tow with a mid sized SUV - and that will not change, for sure - so no easy or good place to carry a generator.

i also dont like the noise, at all.

I also dont want to deal with gas for it, nor maintenance.

for us the ideal solution was 2 panels on the roof, plus we already owned a portable, so ETI added the ZAMP port. All bases covered.

and...

the post above who suggested "2nd panel ready" at build is a clever idea. i wonder how much ETI would charge to add the wood blocking internally at build, and maybe wiring at the ready.