As a new bus owner I have been kicking around a large number of items; with solar being one of them.
In my research the following items have popped out.
1. If only doing the summer season, just mount the panels flat on the roof.
2. If full timing and living off grid in dispersed camping during the winter you will want to orient the rig towards the east to catch solar radiation through the front windshield to warm up in the morning.
3. You should consider being able to tilt your panels for better power gathering during the winter as the sun will be low on the southern horizon.
4. Be very careful of any solar shading if you have panels wired in series as the full coverage of a single cell on a panel will take out all of the panels in the string.
5. Given point four do not put any panels when they might be shaded by the air conditioning units (except maybe for the right side of the bus when it faced to the east?).
6. Make sure the angle of the panels, do not shade other panels.
7. Maybe high wattage/high voltage panels in parallel would be better than any series array setup?
8. Plan some of the panels as dismount setups?
9. Keep all the above in mind when selecting the charge controller(s)? I.E. do not skimp of feed wire thickness or the number of controllers....
I currently have no interest in using any, but may still consider some for my travel trailer for Alaska trip in 2021. However, for our coach, I would probably use the flexible ones because easier to attach, more coverage available on the roof surface without a bunch of brackets. I've read that they aren't as efficient as flat ones though. Figuring extra panels will help to offset that.
Definitely defend against shading, don't wire in series.
One giant seagull poop from above... there goes the charging.
Inspecting/cleaning the roof isn't the easiest job, and lends a degree of danger to your design that has to be managed.
Too many busnuts design on the ragged edge of a minimalist existence, and it is miserable when one teeters off that edge, not to mention those long suffering souls who are sharing that existence.
If catching the morning sun is your heating design, vs a nice way to save a couple pennies in furnace fuel burn... Someone is going to be miserable...
If you didn't know, the front end of the bus loses a lot of heat, and many busnuts construct heavy curtains to completely isolate the driver's area, stepwell and windshields from the rest of the coach.
There's years worth of reading on here at BCM, just scroll back thru the forum.
Keep the neat ideas coming!
Happy coaching!
Buswarrior
But if you used actuators to lift or tilt the panels then cleaning them would be pretty easy from the ground. ;)
FWIW, I just finished installing solar on my bus last month.
I went with 4 residential 325W panels.
There are a dozen reasons to choose residential panels vs the Amazon special dejour, but chief among them was better tolerance and handling of shading.
They are installed in a 2x2 parallel/parallel installation into 2 mppt controllers. Their naturally higher voltage negates the need for series.
They do not tilt and I've gone back and forth and back again on that and decided to just hard-mount them. Waaaay easier and less PITA. ;D
They're on homemade brackets made of angle Al and 3" bar.
The panels are riding about 10" on the curve and 6" above center of the roof (that is one seriously curved roof :o)
I did this for several reasons but the main reasons are heat dissipation (you really don't want to just stick panels onto or 1" above your roof) and to act as shading in hot weather (where it makes a huge difference in cooling the rig).
All in all I'm very happy with it. We're producing ~ 6.5kw a day, during NM fall, and we've paid near 0 attention to orientation of the bus.
If I were to point the bus slightly north of west, I think I'd get an additional 1 to 1.5 kw.
We're now able to boondock and have gone from running the gen two hours a day, to top-off batts and handle large loads, to about an hour a week :)
Hope that helps and regards,
George
Quote from: chessie4905 on October 24, 2019, 04:14:54 AM
I currently have no interest in using any, but may still consider some for my travel trailer for Alaska trip in 2021. However, for our coach, I would probably use the flexible ones because easier to attach, more coverage available on the roof surface without a bunch of brackets. I've read that they aren't as efficient as flat ones though. Figuring extra panels will help to offset that.
What I have heard from multiple places is that the flexible panels cost as much or more than the house panels and then only last a couple of years before they start degrading badly, because of that they come with a very short warranty period.
A decent YouTube channel mostly oriented towards RV: https://www.youtube.com/channel/UCoj6RxIAQq8kmJme-5dnN0Q (https://www.youtube.com/channel/UCoj6RxIAQq8kmJme-5dnN0Q)
Quote from: Dave5Cs on October 24, 2019, 08:14:30 AM
But if you used actuators to lift or tilt the panels then cleaning them would be pretty easy from the ground. ;)
Any suggestions on actuators?
Still doing research but for tilting panels I was thinking of something like the latch assembly for a swinging gate.
Attach multiple panels together with a pivot point that fits into the latch, then you unlock one side of the other to point left or right with an actuator.
(https://www.crystalpoint.com/cpdownloads/public/outgoing/Freds/SwingGateLatch.jpg)
https://www.amazon.com/Weatherables-Polymer-Key-Lockable-Keystone-KLADV-P2-BK-KA-WEA/dp/B07CJHYQSX/ref=sr_1_6?keywords=electric+gate+latch&qid=1571333131&sr=8-6 (https://www.amazon.com/Weatherables-Polymer-Key-Lockable-Keystone-KLADV-P2-BK-KA-WEA/dp/B07CJHYQSX/ref=sr_1_6?keywords=electric+gate+latch&qid=1571333131&sr=8-6)
Does anyone know the name of this type of capture latch or a boating equivalent?
Solar remains on the "to do" list, like anything tech, times offers better and cheaper products. Your report is encouraging and impressive, generating over 6kw.
Placement of panels off the vehicle is a requirement if the bus is located where it is shaded. How are panels mounted and connected to allow removal?
Second consideration for my design is energy storage. Lithium today offers the best performance but most costly. I'd bet it would be used more if the cost was closer to other formulations. The key reason being lithium takes charge at a far greater rate (1C) so more energy can be stored during the day, further reducing the need for supplemental use of generator, not that is all bad, just desirable
We went with three ground-deployed 180-watt panels for our first round. My thought was that if we're operating on solar, I'm most likely not going to be running the a/c. With that being the case, it seemed that being parked in the shade was advantageous. Our three panels are wired in series to keep the current lower, allowing us to run a 50-foot cable between the bus and the panels. That keeps us fully in the shade while the panels are fully in the sun.
Eventually we'll be adding panels to the roof as well.
I have 1950 watts on my rig, 6x 320 watt panels. I run 3 groups of 2 panels in series for 80v nominal PV voltage. I can run the cheaper 8-10 ga wire.
If I could do it over again, I might have done smaller panels so I could go around vents and AC units, instead of looking at building a rack to go over it all.
I run the Victron MPPT charge controllers, I run 2 because I want to add 2 more panels here soon and in the summer I would max out on amps at 1400 or so using a 24v system. I recommend a 24v house bank, you save on wire and charge controllers, a dc->dc converter for house 12v stuff is cheap and works great.
On avoiding series connected solar, I have not had issues. In direct sun, yeah I'll lose some with partial shading on a panel, but in my experience I only lose that panel, the MPPT charger tracks it and it pulls power at 40v rather than 80v, I see it bounce around to 55, 60, 70, whatever to get the most it can.
On tilting - I've considered it, but the risk reward on a bus doesn't add up for me. I want mine locked down, I don't want something to come lose and loose a panel or two. I'd rather add a few more panels to make up for the lack of tilting. If you want to tilt, I admire it and will be a bit jealous, it's just too risky for my taste.
Ground Deploy - I want to add some of this , maybe add a 3rd charge controller and a string of parallel panels I can setup and tilt while boondocking in the shade. Now even in the shade / partial shade in a wooded campspot I'll get 700-1000 watts out of my 1950, during mid day usually, with peaks and valleys as the sun moves.
Realistic Expectations - This was the biggest for me, I have a post on here where I went into more detail, but to be fully solar sufficient you need 2x your daily consumption in realistic harvestable solar capacity. My 1950, in clear skies, I'll see max 1700-1800 in June. With wispy cirrus clouds and whatnot, I'm looking at 1400-1500 most days. Right now I'm seeing 1200-1300 peak, and that doesn't last long in these shorter days. So for me, I need 5 to 10kw of power per day if I'm running AC much. I can maintain just fine if I show up charged, but by the time morning comes and I'm sucking juice as fast as the sun can produce it, I don't gain much. This is why I need those other two manels, maybe another four, but I've only got so much room, so back to ground deploy too. Also, a good generator should be part of the plan, I finally am happy with a 7kw Onan gas genny that meets my needs perfect when catching up on a few cloudy days.
I also didn't see anything there about batteries. In a bus you have options. A lot of people recommend Battle Born batteries and they are good for the lithiums, but super expensive. I'm really impressed with these Valence Batteries right now https://www.ebay.com/b/Valence-Rechargeable-Batteries/48619/bn_114829959 130+AH@12v for $450 Most of these are testing at 95% capacity. The medical devices they come from are switched out yearly or something. I ended up with 6 Telecom AGM batteries I got for $150-ish each or so. 210 AH @12v , yeah they weigh 130lb each, but $1000 for 14kw of battery storage is hard to beat even if it's an older chemistry.
Eddy, what would you think about a site deployable folding rig with powered actuators? My thoughts are, maybe you could have a center stick of panels a few inches off the roof laid flat as a rigid base and then a pair of hinged "wings" with robust frames and pivot points that would swing up and out to deploy, folding in to a 3 layer stack with alignment pins in the folded position, and it shouldn't be too hard to add powered safety latches. Acordian type links could be used to hold the weight when deployed. Something like a small HF winch could be used to deploy each side, and with shafting used to form the winch drum as well as the hinge pins, several sticks could be linked to a single pair of winch motors. You wouldn't get any charging while on the road, but the solar cells would be more protected. Plus it would give you more shade.
Jim
Quote from: Jim Blackwood on October 25, 2019, 11:03:44 AM
Eddy, what would you think about a site deployable folding rig with powered actuators? My thoughts are, maybe you could have a center stick of panels a few inches off the roof laid flat as a rigid base and then a pair of hinged "wings" with robust frames and pivot points that would swing up and out to deploy, folding in to a 3 layer stack with alignment pins in the folded position, and it shouldn't be too hard to add powered safety latches. Acordian type links could be used to hold the weight when deployed. Something like a small HF winch could be used to deploy each side, and with shafting used to form the winch drum as well as the hinge pins, several sticks could be linked to a single pair of winch motors. You wouldn't get any charging while on the road, but the solar cells would be more protected. Plus it would give you more shade.
Jim
If you haven't already see it, you'd enjoy seeing the YouTube videos done by Beginning From This Morning about their solar array. They have panels on the roof which are moved by servos - they tuck in for travel and extend out for use. If I understand your idea it sounds similar to what they did.
Here's the 4th video in their series on the install: https://www.youtube.com/watch?v=wQRnECDIQ8E
Just pull a small trailer that you can deploy as many panels as you need.
Quote from: richard5933 on October 25, 2019, 11:34:40 AM
If you haven't already see it, you'd enjoy seeing the YouTube videos done by Beginning From This Morning about their solar array. They have panels on the roof which are moved by servos - they tuck in for travel and extend out for use. If I understand your idea it sounds similar to what they did.
Here's the 4th video in their series on the install: https://www.youtube.com/watch?v=wQRnECDIQ8E
Yes I have seen that video, it covers deployment, not tilting.
My house battery's are going to be Tesla Battery modules which I will pair with a 6KW split phase 240 volt inverter that works with the Tesla Chemistry.
Kicking around idea's on how to charge the house battery while in motion using the 24volt alternator.
The safest I think would be to use a solar charge controller and switch the alternator from the start battery's to the charge controller and boost charging voltage to 30 volts so the charge controller has the necessary head room to work. Maximum voltage for the Tesla battery pack will be 24 volts.
Any thoughts?
You could get a battery-to-battery charger like the ones that Sterling makes. We've got one to charge our 12v house battery bank from the 24v chassis system. They also have 24v-to-24v. The advantage to something like this would be that it is a true multi-stage charger. You could also do it like you're describing with the solar charge controller, but I prefer to have dedicated equipment.
You can charge direct from the alternator, just keep the voltage below I'm the max voltage.
I used to be looking for Tesla packs until I saw a few blow up. Cost per watt hour those valence ones are hard to beat.
My PV installation is essentially two entirely separate systems running in parallel, so if anything goes tits up I will still have at least 50% of my power production ability. Redundancy is good! I first made a walkway between my two roof hatches, then hinged each panel from that walkway, four on each side; each side of four parallel-wired panels feeds its own charge controller that charges its own bank of batteries, then both banks are combined through Schottky diodes to prevent one bank back-feeding into the other. The panels and walkway also keep the bus appreciably cooler inside because so little of the roof now gets any direct sunlight on it. The panels lock down (at 21 degrees down) for travel, or can be raised to 21, 33 or 45 degrees up depending on the season. I also put two quick-connect water outlets on the walkway, so to wash bird crap / dust / leaves / etc off the panels I get up onto the walkway and just plug in my washdown brush - it's almost fun to clean them this way!
In addition to always having my house batteries fully charged each day, they now also provide power to the start batteries' maintainer chargers, so even they are now solar-charged to 100% every day. For the desert SW of the US there's really no reason to not have solar - there's nearly always ample sunlight all year.
John
Does it hurt a solar panel to be in sunlight with it not connected?
I would like to see some pictures of the folks that have a permanent mount on their buses.
Quote from: neoneddy on October 25, 2019, 10:16:53 AM
I also didn't see anything there about batteries. In a bus you have options. A lot of people recommend Battle Born batteries and they are good for the lithiums, but super expensive. I'm really impressed with these Valence Batteries right now https://www.ebay.com/b/Valence-Rechargeable-Batteries/48619/bn_114829959 130+AH@12v for $450 Most of these are testing at 95% capacity. The medical devices they come from are switched out yearly or something. I ended up with 6 Telecom AGM batteries I got for $150-ish each or so. 210 AH @12v , yeah they weigh 130lb each, but $1000 for 14kw of battery storage is hard to beat even if it's an older chemistry.
Is there any information available on what type of BMS these batteries have internally to them?
Brian, re:bms there are balance leads under the cap. Word is there is a company developing a system that works with its bms wiring. I've seen talk on the DIY RV solar Facebook group.
Quote from: richard5933 on October 25, 2019, 05:57:29 PM
You could get a battery-to-battery charger like the ones that Sterling makes. We've got one to charge our 12v house battery bank from the 24v chassis system. They also have 24v-to-24v. The advantage to something like this would be that it is a true multi-stage charger. You could also do it like you're describing with the solar charge controller, but I prefer to have dedicated equipment.
I dropped them a note, however it looks like they don't support user configurable settings which I would need for my Tesla Battery modules.
I also came across another vendor that I sent a note too: https://ablemail.co.uk/battery-charger (https://ablemail.co.uk/battery-charger)
Quote from: neoneddy on October 25, 2019, 06:09:13 PM
You can charge direct from the alternator, just keep the voltage below I'm the max voltage.
I used to be looking for Tesla packs until I saw a few blow up. Cost per watt hour those valence ones are hard to beat.
Was this in RV usage? Power density wise each module is equivalent to four battle borns. So, needs to be treated with respect and management.
My daily driver is a Tesla Model S that bought five years ago, so I guess you can say that I drank the Kool Aid!!! (The only problem is that it doesn't fly).
Quote from: freds on October 26, 2019, 10:27:34 AM
I dropped them a note, however it looks like they don't support user configurable settings which I would need for my Tesla Battery modules.
I also came across another vendor that I sent a note too: https://ablemail.co.uk/battery-charger (https://ablemail.co.uk/battery-charger)
Check page 11 of this manual: http://www.sterling-power-usa.com/library/2018_green_ultra__Ultra_InstructionsEng_Ger.pdf
I've got the 12v output version, and if it works like mine you can custom set all three charging stages. My reading of this manual shows that you can custom set the output on the 24v version as well.
Best bet for contact with Sterling is to call the phone number on their website. When I've done this in the past, it went directly to the US rep. He called me back quickly, even while he was on vacation. Seems like a stand-up guy.
Quote from: neoneddy on October 25, 2019, 10:16:53 AM
I'm really impressed with these Valence Batteries right now https://www.ebay.com/b/Valence-Rechargeable-Batteries/48619/bn_114829959 130+AH@12v for $450 Most of these are testing at 95% capacity. The medical devices they come from are switched out yearly or something.
I have 6 of these as well as the software to communicate with the internal BMS. Still in initial testing not hooked to solar yet. I'm using with a Victron inverter/charger and so far have been impressed. From what I have been able to determine the U27 138 Ah ones were used, at least most of the ones that seem to be for sale, in Smith electric trucks. My first four were all cycled less that 200 times, the last two less than 10. If you are near Milwaukee you can get them from the guy who is going around buying these trucks for about $300, if you need shipped there are $400. In 6 batteries I have about 660 Ah usable.
The 40 Ah models are the ones used in medical equipment.
Quote from: neoneddy on October 25, 2019, 10:16:53 AM... I'm really impressed with these Valence Batteries right now https://www.ebay.com/b/Valence-Rechargeable-Batteries/48619/bn_114829959 130+AH@12v for $450 Most of these are testing at 95% capacity. The medical devices they come from are switched out yearly or something. I ended up with 6 Telecom AGM batteries I got for $150-ish each or so. 210 AH @12v , yeah they weigh 130lb each, but $1000 for 14kw of battery storage is hard to beat even if it's an older chemistry.
I got an incredible deal on used batteries. A storage guy had 10 AGM "High Rate Max" batteries, 12V. 78 A/hr each that somebody had bought surplus from a cell phone maintenance company and dumped at his place. I asked him if he'd sell them - he said "yes, I was going to take them to the battery recycle place, they offered me $12 apiece for them but it's such a pain in the **s to haul them down there, I haven't gotten around to it. I should though, I need to get them out from in the way". I asked "how much for each? - he said "I told you, $12 - you're doing me a favor so I don't have to haul them". I got that battery bank for $120. They have about 5 years left on their "expected" life span. I put each on a battery maintainer, at 6 Amp charge they all went to "Float" in less than an hour (so they hadn't been sitting around discharged).
I went by a bit later, the storage place was sold and the guy who had them (not that it would do any good because he didn't know where they came from) wasn't working there any more, so it's a buy I can never repeat.
I don't put a lot of load on them but they're working just fine.
No interest in solar, but I'm lovin this battery bank.
Quote from: Oonrahnjay on October 26, 2019, 08:23:52 PM
I don't put a lot of load on them but they're working just fine.
No interest in solar, but I'm lovin this battery bank.
And since you are not supposed to discharge below 50% that is how many kilowatts usable and how many pounds to truck the road?
Quote from: freds on October 26, 2019, 09:46:27 PMAnd since you are not supposed to discharge below 50% that is how many kilowatts usable and how many pounds to truck the road?
Since some b*ts**d stole one of them from my shop, I only have nine. Therefore, it's about 682 12V/A-hrs. or about 8.7 total k/watt/hrs or 4.35 useable. But for $120, who ITF cares??
Quote from: Oonrahnjay on October 26, 2019, 08:23:52 PM
I got an incredible deal on used batteries. A storage guy had 10 AGM "High Rate Max" batteries, 12V. 78 A/hr each that somebody had bought surplus from a cell phone maintenance company and dumped at his place. I asked him if he'd sell them - he said "yes, I was going to take them to the battery recycle place, they offered me $12
I got 16 telecom AGM batteries for free when the telecom decommissioned equipment at my employer. They told me they just scrap the batteries so I asked if I could have them. They had just been on float for three or four years. Never discharged as we had never had a power failure. Not light, but free is good.
This thread has drifted into batteries so how do you guys keep from charging lithium batteries at temperatures below freezing? My understanding is that lithium batteries are destroyed if charged below freezing.
Quote from: belfert on October 27, 2019, 05:20:17 AM
This thread has drifted into batteries so how do you guys keep from charging lithium batteries at temperatures below freezing? My understanding is that lithium batteries are destroyed if charged below freezing.
That is an important consideration if the couch is going to be left unoccupied.
As to preventing damage that is generally the job of the battery management system, some charge controllers also have a temperature input.
Even on a poor solar day you generally get some power which should first go towards warming the batteries.
I am planing on doing IOT (internet of things) local automation using a Raspberry Pi and Node Red as I progress in my modifications.
Further edit: Also lithium batteries do not have to be vented, so can be in a more insulated compartment.
Getting back to that video of the sliding array, while pretty slick it doesn't strike me as particularly robust. No, what I was thinking about should be better able to resist wind loadings without damage, and would have some capability to adjust tilt. Also, any sliding mechanism is inherently more troublesome than a hinged array.
Think tri-fold brochure. It all folds flat but hinges open to the preferred position, the cells protected inside in the transport position.
Jim
If you get the panels installed on the roof, but haven't yet wired them up, does it cause an issue with the panels out in the sun? Should they be covered till wired up?
In my reading, most of the panels out there will do just fine if in the sun but not connected. What do you think happens to the panels with the batteries are full and the charge controller cuts off the flow? There is no heat sink to absorb the output from the panels - it just goes to nowhere until needed.
https://physics.stackexchange.com/questions/71434/where-does-electricity-go-from-a-solar-panel-that-is-not-plugged-in-to-anything
The one thing that I have seen warnings about is open terminals/connections on the panels if left outside. I've seen recommendations of plugging in dummy terminals to prevent moisture and/or dirt from entering the panels connectors.
Quote from: freds on October 27, 2019, 08:45:11 AM
That is an important consideration if the couch is going to be left unoccupied.
As to preventing damage that is generally the job of the battery management system, some charge controllers also have a temperature input.
Even on a poor solar day you generally get some power which should first go towards warming the batteries.
I don't have solar on my bus and probably won't have solar on my bus, but I do have batteries. It is possible I might buy lithium batteries the next time around due to lighter weight and high DOD. Low temperature last winter was -30F. I keep my bus plugged in so the AGM batteries get charged as needed all winter long. I cover the bus over the winter so any solar panels wouldn't charge anyhow.
I have solar for my house that was installed with a combination of DIY and a friend who works for a solar company. Last winter we had so much snow that my rooftop panels didn't produce any power for over two months. Often the snow will melt and slide off, but not when you have lots of heavy snow. I'm sitting on the power company owing me nearly $500 right now. We have true net metering in Minnesota and the power company will write me a check based on the retail value if I still have a credit at the end of my yearly cycle. I expect to get a payment from the power company when true up time comes around.
Quote from: belfert on October 27, 2019, 03:35:08 PM
I don't have solar on my bus and probably won't have solar on my bus, but I do have batteries. It is possible I might buy lithium batteries the next time around due to lighter weight and high DOD. Low temperature last winter was -30F. I keep my bus plugged in so the AGM batteries get charged as needed all winter long. I cover the bus over the winter so any solar panels wouldn't charge anyhow.
If you are going to leave them for months; I think the procedure is to discharge to the 60% level and then disconnect them. They don't need a trickle charge like AGM batteries.
When you select a battery vendor, ask them for their storage procedure. Another option is place them in a insulated box and add water freeze warmer.
If whatever management of a new battery type relies on a steady source of electricity...
That's playing the same dangerous game as counting on the electric company for freeze protection...
If "just sitting there" under certain weather/temperature conditions is going to harm something, without anyone there to deal with it, that's not a good battery choice for most busnuts.
If those conditions come about, there's likely many other distractions, life safety, the ability to travel/access, and the coach is going to have to fend for itself.
Good old golf cart batteries won't mind?
The whole story is hard to find on the internet.
Safety first!
Happy coaching!
Buswarrior
Unlike lead acid batteries, Lithium batteries don't loose power over time so you can leave them for months.About the only thing that will damage them is charging when its freezing.Cold doesn't hurt them otherwise. So if you are storing your bus for the winter disconnect the batteries(also applies to FLA's) and turn off the solar panels(if you have them).
I don't like anything sitting for months that requires power or heat to keep something from getting damaged due to cold. What happens if the power goes out or the heat source fails?
Years ago as a teenager I got shocked by some warming cables for a outside drain. They were cracked and probably not providing heat to keep the drain open any longer.
Quote from: Jim Blackwood on October 27, 2019, 08:45:45 AM
Getting back to that video of the sliding array, while pretty slick it doesn't strike me as particularly robust. No, what I was thinking about should be better able to resist wind loadings without damage, and would have some capability to adjust tilt. Also, any sliding mechanism is inherently more troublesome than a hinged array.
Think tri-fold brochure. It all folds flat but hinges open to the preferred position, the cells protected inside in the transport position.
Jim
That's pretty much also what I thought. It's a very Rube Goldbergian way to do what should be a very simple process, and there's lots of things that can (and probably will eventually) go wrong. Lots of critical single points of failure! The fact that the panels cannot tilt means that he is throwing away a lot of his potential solar harvest. Also, cleaning the panels will be neither easy nor safe; cleaning them needs to be regularly done to preserve their efficiency.
I guess some folk just like high-tech for its own sake. I prefer simple mechanical solutions and human power.
John
"It's a very Rube Goldbergian way to do what should be a very simple process, and there's lots of things that can (and probably will eventually) go wrong. Lots of critical single points of failure! The fact that the panels cannot tilt means that he is throwing away a lot of his potential solar harvest."
Ive been following this guys build for some time. I don't think that lack of tilting panels will even be noticed. In one of his videos he shows running 3 air conditioners from the panels"only". And while I'm sure he will have some teething problems it certainly doesn't look "Rube Godbergian" to me.
There are other examples of using sliding panels on you tube. Also sliding panels means you don't have to get up on the roof to tilt them-a safety concern.
Quote from: belfert on October 28, 2019, 06:23:03 PM
I don't like anything sitting for months that requires power or heat to keep something from getting damaged due to cold. What happens if the power goes out or the heat source fails?
I have lithiums and, as of right now, no solar. I have installed two fail safes to keep the batteries from being charged when below freezing. Both are controlled by digital thermostats. First is a heat pad that the batteries are sitting on comes on about 38° and off at 45°. Second, a latching contactor to totally disconnect batteries from everything, set to 34°
The latching contactor also has a manual switch so, in winterizing the bus, I ran the batteries down to about 60% and unhooked them.
I work on the bus in the winter so I need power, it's always plugged in. My inverter/charger needs 12V to energize and pass 120V AC through so I added an AGM just to keep everything happy. My inverter/charger also has an extra 12V output circuit to maintain the start batteries.