Update on our solar panel system!

[ClydesdaleKevin]

I have determined that the way we use our power, the two Trojan T-105 batteries are more than enough for boondocking.  As long as they fully charge during the day, they last all night and have plenty of power left the next morning until the solar starts charging them up again (I've been turning off the inverter at Midnight every night, and turning it back in the morning).  Even with partly cloudy days, the 400 watts of solar is adequate to charge them up...but with dark cloudy days, it isn't quite enough.  So when we can afford it, I will indeed be adding 300 more watts to the roof...which should be more than enough even with a few dark cloudy days in a row.

I think that having the two Trojan batteries is actually better for us than our old system with six batteries.  This way the battery bank ends up being FULLY charged during the day, whereas the old system, with 705 watts, would only fully charge after a few very sunny days in a row.

Here are pictures of the system.  As you can see, I can easily add three more panels next to the one on the front of the roof, and still be able to walk around up there and keep the roof maintained.































Kev

[Rickf1985]

You definitely have enough real estate for more panels but one thing glares out to me and that is your shadow. You need to get the panels looking at the sun and you will get probably 30-40% more power from them. And keep in mind that an inverter uses a TON of battery power. One amp of 110 volt power draws around 15 amps of power from the battery. That means you can pull down a 100 Ah battery to 50% in 3 hours at a one amp draw. You need top get away from the AC power and your system will be much happier.

[ClydesdaleKevin]

You definitely have enough real estate for more panels but one thing glares out to me and that is your shadow. You need to get the panels looking at the sun and you will get probably 30-40% more power from them. And keep in mind that an inverter uses a TON of battery power. One amp of 110 volt power draws around 15 amps of power from the battery. That means you can pull down a 100 Ah battery to 50% in 3 hours at a one amp draw. You need top get away from the AC power and your system will be much happier.

LOL!!!  Tell that to my wifey.  The only thing the inverter is running is the 24 inch LED TV and the Dish receiver when we boondock.  The Fridge is running on propane when we are boondocking.  For heat we use a Buddy Heater so the fan won't run on the furnace.  But getting Patti to not watch TV?  LOL!!!  I have a better chance of playing poker with God, Buddha, Odin, and L.Ron.Hubbard.

:)rotflmao :)rotflmao :)rotflmao :)rotflmao :)rotflmao

The panels do tilt if I need them to, and right now we are in full sun, with nothing shading the panels all day long.  The angle of the sun, where we are at, is almost ideal on the panels without tilting them.  (The pictures above were taken at the KOA in Beaver, UT.  Where we are now has no trees, so nothing shading the panels).



We only run the inverter to power the TV until Midnight.  We then turn it on after 9am.  By the time the sun goes down we are reading 12.7 volts on the meter...and then the next morning, the batteries are still reading at 12.3-12.4 volts.  All the lights in the RV are LEDs as well.  When we go out for the day, we turn the inverter off completely until we come home.  But even if Patti watches TV most of the day on days we stay in, we are still reading 12.3-12.4 at Midnight and the next morning, provided there was enough sun to fully charge the batteries by around 6pm.  The other day, when the generator stopped putting out AC voltage and I asked you the question about running the Cummings at idle, we had two days of very dark clouds and rain, and the panels couldn't keep up with the demand.  Partly cloudy days or even cloudy days where it is still very light outside don't seem to be a problem.

Kev

[Rickf1985]

But if the panels are not FACING the sun they are still not producing the full power that they are capable of. This is not an issue on a full sunny day but on a cloudy day you need all of the radiation you can get and that is when tilting towards the sun counts.

[tmsnyder]

I bought some Renogy 100W panels for my old RV, they were 42x21 inches according to Amazon.   What are the dimensions of these panels?  B/c they look small in the photos.


Rick's right that if they aren't pointed right at the sun you won't get the rated output.   It's the sine of that angle times the rating, at 90 degrees the sine is 100%.  At 45 degrees it's 71%, at 30 degrees it's 50% output.


My philosophy was I'd rather have more panels on the roof than get up there and adjust the angle. 


It would be interesting to plug the tv, and then the dish, into a Kill-a-Watt meter and see what you're using to run those .Something like this:  [size=78%]https://www.amazon.com/BALDR-Electricity-Monitor-Power-Energy/dp/B01JLT8NSG/ref=sr_1_2_sspa?crid=28VLTJ6G0L9PF&keywords=kill-a-watt&qid=1560170012&s=gateway&sprefix=kill-a%2Caps%2C127&sr=8-2-spons&psc=1&smid=A18B6GJFAVVH5A[/size]

[ClydesdaleKevin]

So far, for the way we use power, the 400 watts along with the 2 Trojan batteries is more than enough to run the TV and receiver for the wife all day long, and then the batteries will let us run it until 11pm before they get down to 12.2-12.3.  And this is even on lightly cloudy days.  If the clouds are REALLY dark for three days in a row, we don't use the TV etc. during the day and can still usually be fine on power until around 11pm, and then we shut the inverter off.  I haven't had to tilt the panels at all so far, as the sun is pretty much right overhead this time of year.

When we're boondocking, we don't use the furnace and keep the fridge on propane...and if it gets cold, we use a Buddy Heater attached to a pony tank.

Kev