Snow Covered Solar Panels January 22, 2017, 08:03:21 pm Here in eastern Washington we have had a very cold month of January with 9 inches of snow on the ground that has just starting to melt in the last couple of days. Our LD is stored in an outdoor RV storage lot with no access to electricity. Normally the AGM house batteries stay charged from the two solar panels even in January. This January that has not happened because of the snow. When I checked today the house battery voltage read 11.41 volts. As I read the LD manual, there is a good chance the house batteries may be ruined given that low voltage. Our LD is a 2010 and the AGM house batteries are the original equipment so it would not be surprising if they need to be replaced. In looking at the LD manual it looks like I should have disconnected the batteries using the disconnect switch which our LD has. I have run the generator twice during January. So questions I have are: 1) do the solar panels have to be completely free of snow to operate?, does running the generator charge the house batteries?, is it likely the house batteries are toast?Thanks,Paul H.
Re: Snow Covered Solar Panels Reply #1 – January 22, 2017, 08:21:21 pm "So questions I have are: 1) do the solar panels have to be completely free of snow to operate?, does running the generator charge the house batteries?, is it likely the house batteries are toast?"I have a favorite spot in California's Sierra Mountains where I like to open the camping season on Mother's Day. One year, in perfectly clear weather, I pulled in to my spot, got set up, ate dinner and went to bed. By sunrise there was four inches of new snow on the landscape. I was forced to use my generator for the next four days because the solar panels had no output at all. Think of snow as you would if you were parked under a huge tree. Solid shade. The generator will charge the batteries but it won't happen fast. Better to rely on the gen-set to provide power when it's needed rather than run your fuel tank down to the point where you won't have it at all.Are your batteries toast? Maybe yes, maybe no. Only you can determine that... if they take a charge and hold it consider yourself lucky. Other's on the board will most likely have comments on that topic.
Re: Snow Covered Solar Panels Reply #2 – January 22, 2017, 08:40:27 pm Paul,While I am not the authority on LDO, I do have a 2015 LD RB.I generally run the generator twice a month under load (roof AC or Heat Pump) to exercise it. This does also charge the coach/house batteries.That being said, I often start the engine for similar reasons (exercise). The truck alternator is said, in the LD manual to do a better job of charging the coach/house batteries. Faster charge. With this in mind, when I want to get the coach batteries to the max 14 volt charge, I start the truck and let it idle for 30 to 45 minutes. I also run the AC or heater at the same time to give them a bit of exercise as well.The manual, I believe, states that the coach batteries should suffer no permanent damage (AGM's) if fully discharged though their life may be shortened. Also, their life expectancy is around 5 years so they may be due for replacement. (Here's a screen shot from my manual).Hope this helps. Kent
Re: Snow Covered Solar Panels Reply #3 – January 22, 2017, 09:08:42 pm I store the 2015 LD with two 100 watt panels & AGM batteries outdoors in CO. You're further north yet, so your solar charging will be even less than mine. Whenever it snows, I go over the next day with my ladder and garage push broom and sweep the snow off the panels. Once the snow is off, I can see the solar panels at work charging the batteries once again. The black glass on the panels heats up real fast to keep the panels free of ice. The house and coach batteries have always been fully charged when I get there. The newer controllers LD uses also charges the chassis battery; a real nice feature. Since all electricity is turned off in the camper, the draw on the batteries approaches zero. I don't use the battery disconnect because I want the panels to charge the batteries. I run the generator monthly but not too charge the already charged batteries but just because its a good practice.I park the camper with the front on about 3" high wood blocks to help keep the melted snow and ice flowing off the panels. I followed the same winter procedure with my previous 2008 LD and it worked just fine.Our 2000 lived in South Florida so snow wasn't an issue. Ed
Re: Snow Covered Solar Panels Reply #4 – January 22, 2017, 10:59:29 pm ^^^^ ThisYou must get to your rig with a push broom and get that snow off. It's a PITA but it is what it is.Interestingly, I do have a battery disconnect that I pretty much only use when I work on the electronics (remember to pull your solar panel fuse too!!). However, we were expecting snow a week ago so I flipped the switch and pulled the solar panel fuse (not sure this latter task was necessary) on fully charged batts. The snow didn't come to pass so I went over yesterday and switched everything back on. Well, the batts were mostly charged but were not full.Here's another trick on this; I went back over today because, well, I can't stop tinkering on Ruby😋 and I noticed something I had forgotten ... when you switch your batts back on the cab radio automatically turns on at least on an ol' 2004 girl. Soooo, sure glad I went back today. There are enough parasitic draws ( solar controller, propane sniffer, other?) so don't need the danged radio sucking juice!! Fwiw, I also pull the face plate on the radio.Good luck!!! The older I get the less I like being on the roof with snow up there but just be careful and move slowly.
Re: Snow Covered Solar Panels Reply #5 – January 23, 2017, 12:02:06 am Another good reason to get that snow off is weight.A cubic foot of snow weighs in the 20# range. Variation, of course, but that's a fair ballpark number.On my little 24' model, the roof is, again ballpark, 8' x 20' or some 160 sf times 20# per sf equals about 3,200# of weight on the roof. Even a modest 6" of snow puts some 1,600# on the roof.Now an LD is strictly a warm climate SoCal designed RV. I wonder if snow load was factored in during the design process? I have removed some 8"-10" of fairly wet snow from the roof , probably close to 2,000#, and saw no resulting damage. That's a good sign. I don't get up on the roof. I use a step ladder and a long handle garage broom and move the ladder all around the camper and pull the snow off. Depending on the amount of snow and road conditions, I'll go over the same day or next to get the snow off.Arizona is starting to sound good. 👍👍
Re: Snow Covered Solar Panels Reply #6 – January 24, 2017, 03:08:17 pm Quote from: Paul H. - January 22, 2017, 08:03:21 pm1) do the solar panels have to be completely free of snow to operate?The individual cells are series-connected, so anything that interrupts light from reaching a cell will kill the output of the whole panel. If a few cells a partially blocked, the limited current they generate will limit the current of the entire panel. The good news is that at about 14% efficient and anti-reflection coated, roughly 80+% of the incident light the panel absorbs is converted to heat. So, a light snowfall during the day will likely melt off before it can stick. When it snows at night, though, you need to get up and brush the panels off the next morning.Steve
Re: Snow Covered Solar Panels Reply #7 – January 27, 2017, 05:37:58 pm Hello, Wizards--I didn't have snow to sweep off the panels (LDy Lulubelle was nestled in the machine shed out at the farm), but I fear her house batts are sad, so looking for wisdom.I winterized her & took her to the farm when we had some decent weather in mid-December, & her batts were at 100%, went out on Christmas Day to exercise the genn & just putter around & her batts were at about 50-ish%. Since we didn't have any weather coming I left her out in the sun, & put her back in the barn on New Year's before the storm came through--she was again at 100%. We've had an ice storm, some rain, some decent temps with lots of clouds, but only one day with sun on the 15th, & when I went to check her the batts were at 55%; I left her out all day, but weather was coming, so I went back out to put her in the shed & the batts were only up to 66%. We've had more crud/no sun, so I'd not been back out to check her 'til I went to exercise the genn again today...& we finally have sun (& it's expected for the rest of the week). Her batts were down to 5% . She's now out in the sun (parked on a gently south-facing hillside with her right feet down to increase the angle on the solar panels as much as I could). I ran the genn for an hour (& turned on the heater in the AC unit, since I'd read some of you talk about putting some load on when you exercise the genn). Her batts went from 5% to 18% in the hour+ I was there, & I'm planning on leaving her out (we've not got any weather predicted for the next 4 days at least).So, my questions are: 1) How bad is bad when the batts were down to 5%? 2) I know cold weather can affect batts, but there was no radio/lights/TV/etc. running, so how/why are the batts draining like that? I don't remember this happening last winter, nor have I noticed it when she's spent several weeks in the barn between trips in warmer weather. What should I be doing differently? 3) I've seen the folding/portable solar panels--should I get something like that to place outside the south side of the barn, & how would I wire it to the batts on the inside? It's probably about 40 feet from where I'd put the folding panel to the batts in the coach--I know there would be a lot of voltage drop with that kind of distance, but I really don't want to have to take the batts out (I know they're heavy)/re-install every time... 4) I'd appreciate recommendations for how to affix something so I can tilt her panels to improve the charging efficiency (& the proper angle). I've used some empty boxes a few times when I've been staying out there to work a bit, but I don't like that when the wind blows--I don't want the panels flopping around only semi-secured, or the boxes blowing across the pasture for me to chase. Thank you, Wizards, for the lessons I'm about to learn.Lynne
Re: Snow Covered Solar Panels Reply #8 – January 27, 2017, 07:47:50 pm How old are the batteries? If 6+, it might just be age. Also, you didn't mention checking the fluid levels in the cells. Have you been doing that? I'm no battery expert, but prior discussions on this forum would indicate a drop to 5% is not a good thing, for sure. You'll get a quicker charge by running the engine rather than the genny, but the question here is whether the batteries hold the charge. You can search the forum for "phantom draws" or similar and find a lot of threads. -- Jon
Re: Snow Covered Solar Panels Reply #9 – January 27, 2017, 08:39:56 pm Lynne,Not knowing the lay of the land and your LD sheds proximity to a 110 outlet but it may be advisable to rely on a more permanent source of power to keep your batteries charged.Having access to an outdoor outlet myself, I have not had to rely on its power. Couple that with a "call code enforcement" neighbor, I am reluctant to draw too much attention to my LD.Are there regs limiting power to your shed? A qualified electrician could hook you up with little trouble if the distance from existing power isn't too far.Battery wise, which type are you using? AGM's can take a full discharge but from what I've read it does shorten their overall life.Personally I alternate between running the truck and the genny every other week or so to get the batts up to charge and exercise everything else. Good luck.Kent
Re: Snow Covered Solar Panels Reply #10 – January 28, 2017, 04:47:48 am Hi Lynne. Your biggest battery drain is the Propane detector or a light left on somewhere. Some detectors draw in the 50 to 150 milliamps per hour ballpark. That adds up after a few days. To avoid legal liability issues, there is no on/off switch, if you forget to turn it on. You should use your battery disconnect switch to eliminate all power drains. That will turn off the propane detector also. The solar will still work, if you leave the solar fuse connected, but shouldn't discharge the batteries. You could also disconnect one end of the wire between your two 6 volt batteries. Tape the end of the wire and don't short it to anything. A battery produces electricity by a chemical reaction. Cold temperatures reduce reaction speeds, hence poorer performance when they are cold. The worst part is a discharged battery mostly contains water instead of sulphuric acid, and will freeze easier. Trying to charge a frozen battery can often lead to an explosion, so be careful. Because of the low temperature I doubt that your batteries were harmed by the low charge state, but don't leave them that way for too long. RonB
Re: Snow Covered Solar Panels Reply #11 – January 28, 2017, 05:47:24 pm Thx, Jon, Kent, & Ron B--I should check the age of the batteries...they were in when I bought her in December '13, I I guess I've assumed they were AGMs (yeah, I know where that can get me) because her previous owner told me I didn't need to water them--in fact I think that compartment's only been opened once..when he showed me the rig in his driveway. There are 110 outlets, but we turned off the rural electricity at the farm several years ago. The pump for the well to water the cattle is on a solar panel & there wasn't any reason for electricity full time in the shed since Dad was gone/no tinkering in the shop area/etc.No lights on (I always check that back bunk switch/the white backup lights, since the gremlin issue last summer).We've had pretty good sun the pat couple of days, but there may be some snow tonight, so I'm going out to put her in the shed--guess I'll go before it gets too dark so I can look for that battery disconnect switch.Thx, so much, everybody. I knew I'd get the help I need. Lynne
Re: Snow Covered Solar Panels Reply #12 – April 12, 2017, 05:27:40 pm As a followup to my original post, I did use a step ladder and a push broom to clear as much of the snow off the roof as I could. The two solar panels and the 6.5 year old AGM house batteries are working fine. Also no interior leakage from the snow. So a happy ending to a cold and snowy winter in the NW.Paul H.
Topic: Snow Covered Solar Panels (Read 447 times)
previous topic - next topic
Topic: Snow Covered Solar Panels (Read 447 times)
previous topic - next topic