Chevy Astro Van Solar Kit

[kylakemike]

Greetings all,
It has been some time since I have reached out but now appears to be the time. I would like to add solar to my van and hit the road. I have reviewed many of the solar and electrical posts and believe I can exist quite nicely on 300 watts. I am a single dweller residing in a 1995 Chevy Astro van. My electrical needs will be:

Powering an ARB 50 quart refrigerator
12 volt Koolaire air conditioning system
HP laptop
Cell phone and other portable charging
Recharging cordless power tools from time to time
Potential addition of a satellite system
A comfort fan
12 volt lighting

Am I correct in assuming that 300 watts with the appropriate amount of battery storage will cover these items? Additionally reviewing the Renogy web site as provided by Bob shows a 3 panel kit for $504.99. This system will require the use of 3 panels. The van can accommodate 3 so no problem. I am wondering if I would be better served to purchase one 300 watt panel and have Renogy suggest the remaining pieces of the kit. The 300 watt panel by itself costs $264.99 It seems that mounting one panel would be easier than mounting 3 panels.

Additionally I will need house batteries. This system will be independent of the van starting battery. I have no problem with AGM as vent less would be better for me. I already have a 750 inverter. What size battery or batteries should I purchase?
Sooooo……I am at the mercy of your wisdom. Anyone care to chime in and provide a non-electrician with some guidance? Thanks in advance and I apologize for any redundancy.

Thanks so much

 

[LeeRevell]

From the study I have done (in part reading on this forum) I think you may have the cart before the pony.  You should first total up the daily amp/hours of power you expect to use for your devices (this will be a short time for some, longer term for others), then consider how much battery amp/hours you need to power this load, keeping in mind you don't want to drop the batteries below 50% in one day, or before you recharge them.  So, if your daily load were 100AH, you'd need 200AH in batteries.  Add a bit for some 'wiggle room', due to cloudy weather, etc.  THEN calculate the needed solar wattage to keep the batteries charged.
Do a search for Sternwake's long but thorough lectures on this, and on just what battery charging really involves.

This will give you a good jumping off point.

 

[WriterMs]

Yes, Stern Wake has an encyclopedia of expert knowledge posted -- and that's just in the forum threads I've read in the past few months.

I also wonder, however, about your idea to talk with Renogy. If you list the wattage of each of the appliances in your list and talk to them, perhaps they can "do the math" a lot faster.

Also, from your handle, it looks like you may originate from the same region of the country as me. Last year, my final camping weeks were spent in the primitive campgrounds of LBL (Land Between the Lakes). Lovely in the Fall.

 

[akrvbob]

You have a good plan, based on what you are planning to use I think 300 watts is a very good choice. It will easily meet your current needs and should be able to handle a Satellite system. I assume you mean for satellite TV. If so you can;t get by with less and may need to add more.

I have 200 watts and when I added my Sat TV receiver and TV it wasn't enough. I have 380 on my van for a total of 570 so that was plenty, I swim in power, but I'm not 100% certain than 300 will be enough, but probaly.

A 300 watt panel will be high voltage, I'm not certain that Renogy sells controllers that control that much. Be sure to find the voltage of the panel and get a controller that can comfortably handle that much. I'd give serious thought to the Midnight Solar Kid controller.
http://www.solar-electric.com/inver...e-solar-kid-mppt-solar-charge-controller.html

Buying each component separately will involve a learning curve and cost more, buying the Renogy kit will be cheaper and simpler and will work perfectly well, probably not quite as well but plenty good enough.

If you can handle the off-gassing buying wet acid golf carts will save you a lot of money and are much easier to keep healthy and last longer. AGMs are much more fussy on how they are charged and really do not like to be charged by solar. In less you devote a lot of time and effort to your batteries, Golf carts will last longer and be happier.

I don't worry about off-gassing, I think it is a very minor risk. But if you aren't comfortable you can always get a vented box and solve the whole problem. Golf carts will be much cheaper and last longer unless you spend a lot of time taking care of AGMs.

If it were me I'd get a pair of golf carts, probably Trojan T105RE.
Bob

 

[kylakemike]

Yes, Stern Wake has an encyclopedia of expert knowledge posted -- and that's just in the forum threads I've read in the past few months.

I also wonder, however, about your idea to talk with Renogy. If you list the wattage of each of the appliances in your list and talk to them, perhaps they can "do the math" a lot faster.

Also, from your handle, it looks like you may originate from the same region of the country as me. Last year, my final camping weeks were spent in the primitive campgrounds of LBL (Land Between the Lakes). Lovely in the Fall.

Thanks WriterMs. Yes I am from the Northern end of Ky Lake. Grew up on those lakes and have spent many nights camping, swimming, fishing and generally enjoying ourselves. 

I certainly plan to speak to Renogy as I move forward. I simply needed a jumping off point to get the process rolling. 

Thanks again.

 

[kylakemike]

You have a good plan, based on what you are planning to use I think 300 watts is a very good choice. It will easily meet your current needs and should be able to handle a Satellite system. I assume you mean for satellite TV. If so you can;t get by with less and may need to add more.

I have 200 watts and when I added my Sat TV receiver and TV it wasn't enough. I have 380 on my van for a total of 570 so that was plenty, I swim in power, but I'm not 100% certain than 300 will be enough, but probaly.

A 300 watt panel will be high voltage, I'm not certain that Renogy sells controllers that control that much. Be sure to find the voltage of the panel and get a controller that can comfortably handle that much. I'd give serious thought to the Midnight Solar Kid controller.
http://www.solar-electric.com/inver...e-solar-kid-mppt-solar-charge-controller.html

Buying each component separately will involve a learning curve and cost more, buying the Renogy kit will be cheaper and simpler and will work perfectly well, probably not quite as well but plenty good enough.

If you can handle the off-gassing buying wet acid golf carts will save you a lot of money and are much easier to keep healthy and last longer. AGMs are much more fussy on how they are charged and really do not like to be charged by solar. In less you devote a lot of time and effort to your batteries, Golf carts will last longer and be happier.

I don't worry about off-gassing, I think it is a very minor risk. But if you aren't comfortable you can always get a vented box and solve the whole problem. Golf carts will be much cheaper and last longer unless you spend a lot of time taking care of AGMs.

If it were me I'd get a pair of golf carts, probably Trojan T105RE.
Bob

Hi Bob. I was hoping you would chime in and am grateful you have. I believe I will follow your recommendation and stay with the Renogy kit as well as the Trojan batteries. Thank you for the input. I assume the batteries will be wired in series? Is this correct? Due to budget concerns I will stick with the 300 watt system. The addition of a satellite system is not something I require as I have numerous other avenues with which to be entertained. Concerning the batteries, do you not vent your golf cart batteries?

Thanks again for all of the input.

 

[SternWake]

The ARB is pretty efficient.  Make Sure the cooling unit vents on the bottom are not restricted.

I've really no Idea the consumption of a satellite receiver.  How much you plan on using it and the Tv can allow 300 watts to be more than enough or not nearly enough.


Same for the Laptop.

Your cordless power tool battery chargers, might not like a MSW inverter.  They might smoke quickly, or prematurely, or never at all.

I bought a 400 Watt pure sine wave inverter, mainly for my Lithium Makita drill and driver, but no proof it would have smoked itself on my MSW, and I never will.  Replacing batteries or the charger itself cost as much or more than a new drill.

2 trojan t-105's on 300 watts of solar would make for  pretty Happy t-105s, Unless you watch Sat TV all day long with your laptop on as well.

They will offgass only when charging from about 85% charged to 100% charged.  A Recent thread exists on this topic

 

[kylakemike]

Thanks so much Stern. I have been reading all night and think I am getting my mind around all of this. Concerning recharging battery powered tools, I think I will have access to enough shore power or the generator of others from time to time to charge these versus off my system. As far as satellite goes that is way in the future or not at all. I am a sports junky and do like to watch but can do that from my laptop with internet access. I will probably listen to my CC Crane radio more than anything.

Glad to hear about the ARB. I know it is expensive initially but with this system it doesn't make sense to go any other way.

 

[SternWake]

I was impressed with the build quality on my Friend's 50 liter ARB.  It seemed to run for about 15 minutes, then off for an hour when set for 26f in 70 to 75f average  ambient temperatures.  It consumed about 14 to 16 AH in 24 hours. with about 10 lid openings in that time.


Internal temps, according to the ARB would rise from 21 to 29F at which point the compressor would kick on and lower it back to 21f.  At this setting things would just begin to freeze.

I never saw it draw less than 40 watts, and the maximum I saw it draw was 65 watts.  Perhaps on initial cooldown it might draw more.  The Danfoss BD35f compressor is adjustable speed. from 2000 to 3500 rpm, ~2.2 amps to 6.5 amps.  At 3500 rpm it can power an 8 cubic foot fridge, so the compressor is not working hard at all powering a fridge 1/4 that size at slower rpm.  The ARB varies the compressor speed.

I use a front loading Vitrifrigo fridge that is also 50 liters.  Mine has extra insulation and the cooling unit is very well vented, and actually consumed less then the ARB did during the same weather, and with more door openings.   My VF does not adjust compressor speed.  but it is adjustable by adding resistance to the thermostat circuit.  I removed my 270 ohm resistor to drop compressor speed from 2500 to 2000 rpm.  The slowest speed the compressor can run and maintain a sub 50% duty cycle the more efficient it is.  Mine rarely exceeds 25% duty cycle, or 15 minutes per hour.  My compressor runs for ~5 minutes on and 15 to 20 minutes off and is in the 12 to 15AH consumed per 24 hour range  at 75f average in my usage.

 My friend's ARB also had the extra insulative cover added to it.

I primarily charged my Makita batteries off of the grid, but there was times I needed to charge them when that was not an option and progress came to a halt while I fished out my corded drill and extension cord and plugged it into my 800 watt MSW, and had to go easy on the trigger as it would trip the inverter at max load.

I was not willing to risk the Makita charger on my cheap 800 watt MSW inverter and ordered this that night.

http://www.amazon.com/Wagan-EL2601-Elite-400W-Inverter/dp/B007Y4BL1C

The price was down to 120$ at one point.

I pretty much only use the PSW inverter now, as it is quieter and more efficient.  The Makita charger can draw 250 watts but only does so briefly, in pulses and drops to about 45 watts between 250 watt pulses.

Are you sure you can fit 300 renogy watts on an Astro roof?

I only have 198 watts.  In summertime it is more than enough, in winter not quite enough.  It really depends on how much I use this laptop.  I would enjoy 300 watts and so would my batteries.  I'm getting 10.7 amps as I type from my Solar at 1Pm at 33' north, but 3 to 6 of those will go to laptop and fridge and fans.  15amps would make me more happy.  Can't have too much solar, but one can easily have too much battery capacity for their solar.  If cycling the batteries daily, too little solar for too much battery capacity can decrease battery longevity, even if the solar is capable of returning what is used.  AGM batteries really enjoy higher charging rates and become petulant when they only get low and slow solar day after day, cycle after cycle.

One way to use less battery power is to use a dc to dc car adapter for the laptop. Search for a 'car adapter' for your laptop.  Mine was 22$.  Much more efficient than using an inverter to power the original power brick especially if that is the only item being powered by the inverter.
 The only issue is the ciggy plug will eventually wear out passing 7 amps, and waste battery power as heat until that failure point.

Inverters are also electrically noisy, and might knock out OTA tv or radio stations, and maybe even those with very strong signals in that specific area.  Some LED bulbs are guilty of this too.  My Laptop car adapter can knock out one of my strongest TV stations and is quite annoying.

I replaced my car adapter's ciggy plug with Anderson powerpoles, the 45 amp versions which I make wide use of in many locations.  While I have 7 ciggy receptacles all over my VAN, all wired thickly with 10awg wire, I only use them for sub 4 amp devices, and in fact they are only ever asked to pass about 1 amp when I do use them these days.  Ciggy plugs are just poor electrical connections that will at some point cause issues, especially in the 6+ amp/ 75 to 80 + watt range.

I found there was a significant voltage drop on the ARB power cord and ciggy plug.  It was one of the  better designed ciggy plugs, but still prone to voltage drop and heating and would still back its way out of the receptacle over time requiring reinsertion.

I cut the cord in the middle and installed Anderson powerpoles.  The Original ciggy plug can still be used, but better to bypass it.

This goes for all compressor fridges which come with a ciggy plug.  Bypass the ciggy plug and efficiency and reliability will increase.

 

[akrvbob]

Yes, the Trojans will be wired in series which is easy.

You can probably get by with 200 watts without the Sat TV but it doesn't cost much more for the extra panel and your batteries will be happier and last longer. I'm pretty sure the longer life of the batteries would eventually offset the extra cost of the panel. Plus, in winter during a winter storm you'll be fine with 300 watts but you might be struggling with just 200 because the sun is very low and the days are so short.

No one ever complained about having too much solar--and I'm a man with too much solar!

I've had unvented lead acid batteries in all my live-aboard vehicles for 13 years and I always plan to. There is a small risk but it is so small I just don't bother with it. I did buy a pair of Full River AGM golf cart batteries and after three years they are like new. I don't think I'll ever buy AGMs again.

Wet lead acids do require some work, so you have to be honest with yourself. If you won't do the work to check the water every month or two, you should get AGMs.

However, if you have any kind of a breathing issues then AGMs are a must. I don't so I don't use them.
Bob

 

[kylakemike]

Stern thanks so much. I appreciate that you have taken the time to address many concerns that I have not even considered. As for the ARB , the reason I have chosen it is due to the top loading. I believe I can fit it between my front seats as I do a regular cooler now. I appreciate the insight as to the cycling as well. I am a bit of a geek and appreciate the fine details as well as work arounds. Concerning your friends ARB, was the insulative cover a factory order?

As far as the PSW versus MSW issue. I currently have a cheapo 750 watt HF MSW. I am certainly not opposed to spending the additional coin for the appropriate PSW provided I actually need it. The Koolaire, ARB, laptop (have the 12 volt brick on my list to order) lights, cell phone and iPAd will all charge from 12 volt. I will not cook with electric. So I am wondering if I truly need a PSW or is that money better spent elsewhere? I looked at the Anderson Powerpoles and agree that is the way to go. I hate the ciggy outlets and plugs. I am assuming I will need to wire this into some sort of fuse block and power off of that. Sure hope you guys are here for me when I do the install.

I measured the top of the Astro van and it appears I have enough room for the three panels although the forward most panel may be further forward than I like. However I plan on doing more living than driving.

Thanks so much Stern. I owe you a beer at our first get together.

 

[kylakemike]

Thanks Bob. I think I will stick with the 300 watts at this point and go with the Trojan batteries you recommended. I do not have breathing problems and keep my van in a vented state at all times anyway so I suspect I will be fine. Any concerns with having the Trojans inside in the winter when I have my Buddy propane heater running?

 

[WheelEstate USA]

I wouldn't run the heater by the batteries, just as you wouldn't wire the inverter too close. 
Our 122Ah house battery (fed by 100W) is under the bed at the back where its easy to service. Never a hint of fumes.
Will be adding to the system shortly.

I might recommend a roof (ladder) rack with gutterless mounts to get the panels up off the roof and put the weight in the right places up there.
I'm currently setting up to put a set on our rig. I will be bolting 1 1/4 angle to the racks running front to back and the panels fastened to the angle. Basicly, the panels are sitting in a tray. Eventually, we'll have 4-100W.

 

[WheelEstate USA]

I like multiple panels. Say one goes bad or a limb falls on one

 

[kylakemike]

Thanks bindi&us. Good advice.

 

[akrvbob]

I just measured and my propane stove is literally 3 feet from the Trojans. I have always cooked inside my vehicles and have always had lead acid batteries inside with them. No problems so far, but it's only been 13 years so that may not be enough time. I'm willing to take the risk.

However, I can NOT tell you what to do you have to take your owns risks.
Bob

 

[SternWake]

 Concerning your friends ARB, was the insulative cover a factory order?

The cover was certainly made specifically for the ARB, and not a homemade jobbie, so Yes i assume it is factory product.

He got the ARB fridge used from a friend who i do not know, and the cover came with it.

If you do not need the mobility of a chest style fridge, then one could make something much more effective, to increase efficiency.

But with 300 watts  of solar, you will not need to, unless you just really want to.

 Foilfaced Foamboard insulation, bamboo skewers, and some Nashua Flexfix tape.  Just leave room around the cooling system vents, and add fans, dozens and dozens of computer  fans.

Keeps the locusts at bay.

 

[akrvbob]

Amen on the locusts, brother!
Bob

 

[kylakemike]

I spent last winter with my Mr. Buddy and a 20 lb tank inside this van so I suspect I will be just fine. Thanks Bob.

 

[kylakemike]

Thanks Stern. Once the ARB is in my van it won't come out.