Everything Solar - All member topic

MSN Member · March 16, 2009, 08:35 AM

Sent: 9/16/2002

Hi! I have a solar-powered motion detector flood light I use on the RV when I camp out in the desert, and because it works so well I'm looking into expanding use of solar power.
I can get a 50-watt panel with regulator for about $350.00, which I think would be sufficient for my on-demand water pump and coach lights, w/o having to run that very loud free-standing gen. The ultimate goal will probably be to do away with the gen entirely, which I could do easily if I wasn't spoiled by (still a bit hard to believe, lol) microwave cooking miles from the nearest power line. And maybe a bit of tv to keep up on the news. (ok, ok...actually to keep up on the Gilmore Girls).
Has anyone had experience using solar power in their RV? I'll get a book on it sooner or later, (I'm already checking them out)but nothing is quite like first-hand experience. For example, would I run into any conflict if I DID run the gen while the solar was still connected? Any hints about the wiring? When I do look at a total conversion to solar, what wattage would be sufficient for the micro and tv, and should I wire ALL the solar together or try to have individual supply panels? And can the batteries handle all of this ok? (Both batteries are brand new and good quality)
I understand most solar panels in RV's are connected to make 200 to 500 watts, and if that's what would work best I won't try the "50-watt-panel-at-a-time" route but smash open the piggy bank and get it all in one. But is it worth getting that extra wattage, just for micro and tv, if the 50 watt panel can handle everything else?? Also, the question of what converter I would need comes up, and would it change if I went to the higher wattage?
I'm sure a good book will answer some of these, but again I really value first-hand experience. Any ideas/comments? All will be appreciated!

AC-Craig · March 16, 2009, 08:35 AM

I do not currently use solar, but am researching it for my house and RV. In the RV, I would run only DC appliances. Changing DC current to AC current requires an inverter and is pricey, more than I would want to pay to run a microwave oven.
Most everything else you can buy can be built to run from DC power.
Also, do your homework on batteries. RV deep cycle batteries are not the same as solar deep cycle batteries. AC-Craig

MSN Member · March 16, 2009, 08:36 AM

Thanks for the info. I didn't know there was a difference between solar and RV deep cycle batteries... So, using a solar panel to keep my RV deep cycle batteries fully charged isn't workable? Or maybe just isn't advisable?
Yes, I pretty much DO do the homework first.
The battery shop where I just bought my two new batteries~vehicle and deep cycle~ is also the place with the solar setup for sale, so I'm a bit curious why they didn't mention that possible problem. I'll go back and ask.
It's amazing how FEW solar info books are out there... Barnes & Noble only had one in stock; (I could order several) Borders had two, but one was strictly for installing solar in new house construction. The public library is my next stop...
When I was considering the solar set-up, the man at the battery shop said I could just run some #10 wire from the solar regulator straight to the batteries to keep them charged, and he said my goal of running the 'on-demand' water pump and coach lights would be easily met by the 50-watt panel.
I'll look for more input here; and return to the battery shop for more info; and make a run at the public library, so between these sources I hope to learn whatever I might need to know before embarking on the Solar Power journey...
Thanks for the input! I do appreciate it...

AC-Craig · March 16, 2009, 08:36 AM

There is a ton of stuff on solor energy on the internet. I am a member of the MREA- Midwest renewable energy association and they sell books and have a web page as well as others. Home Power Magazine is a good resource as well.
As for the batteries, it depends on usage. The lead plates in a normal RV or car battery is a porous cell lead plate. The real solor deep cell batteries are solid lead plates. For camping on the weekends, an RV deep cycle battery will be fine, but if you are a full timer, a higher quality battery might be a good idea. And which ever battery you have, keep the batteries charged and don't run them down below, I think 80%, of the full capacity. I am still learning this subject as well. Kraig (AC-Craig)

MSN Member · March 16, 2009, 08:37 AM

Thanks for all the comments! I printed out a lot of stuff from phred's info, and will check out some of the other sites after I digest some of this. From what I gleaned from quick scanning, it looks as if I could use that 50-watt (and regulator) panel for my water pump and interior coach lights, w/o too much problem or expense, but if I want to use my microwave I'll be getting into mucho bucks and equipment, from inverter to more panels and gauges and controls...~sigh~
Solar sounds like what I'll probably be getting into sometime in the not too distant future, but for right now I won't go beyond perhaps a combination of that 50-watt panel and the noisy generator. We get so much sun here in Nevada it seems downright un-American not to use it, but I'll need to digest a lot more info before I start shelling out the BIG $$!!

MSN Member · March 16, 2009, 08:37 AM

After looking over all the info, one glaring fact emerges: I simply don't have anywhere to put all the batteries I would need to go totally solar. I can do the 50-watt panel, maybe even go to 75 watts, to keep the water pump and interior lights going w/o either running the vehicle or using the exterior Gen, but the microwave isn't worth all the additional expense. Especially since I just now bought brand new batteries, both 12v deep cycle and vehicle, and everyone says the 6v would be better. W/O that 12v deep cycle, I would have room for about 4 6v batteries, so maybe in a few years when this battery is showing it's age I'll consider that. For now, it seems my options are: Take the generator and microwave both, or leave both at home.

MSN Member · March 16, 2009, 08:37 AM

An update, just in case anyone is following all of this... I found my battery shop would swap the new 12v deep cycle battery for two deep cycle 6v batteries, (with me paying the difference, of course)so I did that. I installed them and am in the midst of installing a 120w PV panel from RVsolar. As long as I don't use the microwave, this 120w system should take care of my electrical needs. I ignored the #10 wire they included with the kit and went to #8, even though I really don't have any great distance to run it. I figured if #8 size wire is better than #10 for a long run, it's probably better for short runs also.
I am also installing a catalytic heater, needing only the connecting hose between the old connection and the new heater.
With all this new stuff, I'm looking cross-eyed at the old converter/charger. I'm pretty sure it's Original Equipment, and has over-charged my batteries in the past. I want to replace it with newer electronics, but I want to include a decent battery charger with it. Anyone replaced their converter? I'm looking at the ones Campers World has, but I don't know if it's worth it to get their best, that 'Statpower Truecharge 40+', but it may be serious overkill. Anyone have it? My other choice might be the 7200 so many people seem to like (at about 1/2 the cost).
Any comments/suggestions?? All appreciated!!

Collyn down-under · March 16, 2009, 08:38 AM

Because at least half of all motorhome owners free-camp (boondock??) a great deal of the time solar is used very extensively in Australian RVs.

Unlike what appears I understand to be US practice, many use 240 volts AC via an inverter (as with most of the world we do not use 110 volts).

My own fully off-road vehicle is set up like that and runs a satellite telephone (essential in the outback), 70-litre fridge, heaps of lights etc. It runs from two by 80-watt solar modules and has not run out of power once since 1996.

My home, in Broome (north west Oz - latitude 18 degrees) is 1250 miles from the nearest city (Perth) and has no facilities except bore water. Home which we built ourselves, is a hi-tech steel and glass structure. It has all 240 volts standard appliances - fridge, dishwasher, washing machine etc, about 30 outside and inside lights, spa etc. Everything runs from solar. We do not use a generator. It even runs an extensive irrigation system.

We generate about 12 kW/hr/day and do not run out of power at home either! A very large number of Australians living outside our main cities have systems like mine.

From the sale of my books and feedback from the USA it seems we use use solar very much more extensively -possibly because we obtain a govt rebate of 55%.

Unlike US practice we not use 24 volt very much. It's fine for small cabins - but I believe thinking along 24 volt lines is hugely holding back the more extensive use of solar.

I hugely admire Phred's writings and generosity with his time -but do not feel they reflect current thinking. It's not greenie power any more!
Collyn

melyash · March 16, 2009, 08:38 AM

If your looking for a charger to run off AC and not solar, then Xantrex is the way to go. It is a multistage inteligent charger. Can do multiple banks of batteries as well. As for books, I do suggest "Managing 12 volt systems, by Harrold Barre.19.95 from amazon. The book also has examples and diagrams of systems with solar and a generator. It breaks out what you need, and WHY you need it, and explains it in a logical sequence. He goes thru everything from a small RV with one or two days dry camping to Cruising Yachts with weeks of power available. Harrold does all the explanation in a logical fashion, so you can start visualizing what you need for your rig by the examples he shows in his. He gets into everything from why the alternator/voltage regulator on your rig is not the optimum system to solar, to intelligent chargers, to wind power. Matt

Collyn down-under · March 16, 2009, 08:38 AM

Its easy to think in watts - watts = volts X amps so if we speak of 700 amp/hours we must know trhe voltage for it to be meaningful. I assume tho you have 12 volts?

We get about 210 amp/hours/day - but we use a 48-volt battery system - that equates to about 850 amp/hours at 12 volts.

Modules- currently 28 by 64-watt Uni-Solar. These are the ones to use if you live somewhere hot as they do not lose output as they warm up.

Whilst accepting 12 volt stuff generally more efficient, it's extremely difficult to run at that voltage (or even 24 volts) in a big home, as the cabling needs to be huge to avoid volts drop. We have a large property with a need for power in various places so here again the only choice is (our) 240 volts, 50 Hz.

If you consider that voltage drop is likely to be 5% - yet a really hi-tech inverter is 94% efficient - the difference is next to nothing - altho I accept totally your argument re fridges - most domestic ones are energy gobblers - we use a NZ designed Fisher & Paykel which draws about 1500 watt/hours/day. Also hugely bigger range of equipment.

Yes - we use compact fluros extensively - they use 25% of the energy for the same light output as incandescent.

Where you do need to be careful is water pumping. We use 48 volt dc motors and match punp very carefully to load.

A lot of my stuff was originally experimental as I write books on this subject - mostly RV oriented.

OKA engine is military version of the British Perkins 4 cyl. 4 litre turbo -diesel. Truck has 1875 mile range before refuelling - as some of our desert tracks may involve 1000 miles betrween any source of fuel (or anything come to that!) its comforting to have a good reserve.

Chassis is Australian designed and made, massive box section. Axles are US-made DANA, gearbox is Spicer and transfer box is Chrysler.

Have a look at my website
www.caravanandmotorhomebooks.com Colyn Down Under

Collyn down-under · March 16, 2009, 08:39 AM

It's not uncommon to have only 10% or so lees solar input with flat mounted solar modules. It is because solar irradiation is often diffuse. Highest input is usually on a bright day with the odd low cloud. Some sunlight gets bounced back from earth and reflected back again from the clouds. I live only 400 metres from the Indian Ocean and it's very common here. Collyn down-under

Collyn down-under · March 16, 2009, 08:39 AM

I have written this piece in two parts. The first is an overall view. The second part contains technical explanations and data to back up that overview. I would appreciate feedback - as to whether it aids, or hinders access. As it will be reproduced also in the USA I have used the term 'RVs' throughout.

WHAT SOLAR MODULES REALLY PRODUCE
Solar modules can and will only produce the output claimed by their manufacturers if they are used in specific circumstances. Typical RV usage is not one of them.
Outputs vary from type to type, but in typical RV installations most solar modules produce a bit over 70% of their apparently claimed output. Many modules have a small panel on their rear face that shows what they actually produce. For an '80-watt' module this is usually about 58 watts.
Whilst this may seem misleading it is defendable. (The explanation is technical and is provided in the second part of this piece).
Two Main Types of Module
There are two main types of solar module: for the purpose of the first part of this explanation they may be seen as Uni-Solar and the Solarex Millenium series, and the rest. One type is not inherently better than the other. They simply have different characteristics that cause them to be more effective in some conditions than in others.
Most solar modules produce less power as they heat up - as much as 20% in seriously hot places like the north of Australia, and they start losing this power from only a few degrees above freezing. Uni-Solar and Solarex Millenium modules use a different technology. They produce slightly more power as temperature rises.
Because the power output of most solar modules falls as they get hot, from around 35 degrees C (95 F) onward, a 64-watt Uni-Solar module produces much the same output as an 80-watt most anything else. The same ratio is probably true of the Millenium modules, but I have no direct experience. As they are about 15% cheaper in most countries this can sometimes be a considerable benefit
Uni-Solar modules are also less affected by partial shadowing. If most panels are shadowed by an area even as small as a human hand, they lose virtually all of their output. Uni-Solar modules lose only that area shaded. It is claimed that some (but not all) Kyocera modules are also more shadow tolerant.
No solar module will work in complete shade. I need to spell that out because after I stated (elsewhere) that solar modules produce a small output under high-intensity full-spectrum light, this rapidly turned into 'Collyn says they even work under street lights'. They don't.
The above would appear to be an overwhelming argument for Uni-Solar and Solarex Millenium. This is not necessarily so. Their heat advantage is only really worthwhile above 25 degrees C (77 F) or so. And a big downside for many is that, because they are less efficient, they are much larger (40% or so) than other modules. That's why I use two Solarex 80-watt modules on my OKA truck, and 28 by 64-watt Uni-Solar modules on my 5 hectares (about 10 acres) at home.
In practice it is safe to assume that you will get 58 watts from an 80-watt most-anything module, and about 55 watts from a 64-watt Uni-Solar module.
The amount of energy you will capture each day can be readily worked out by taking the true output of the modules (or about 72% of what it says on the marketing brochure) and multiplying that by so-called the Peak Sun Hours typical for where and when you are going. Maps showing this can obtained from meteorological offices, but their's need translating, and (for Australia) from all of my books. Peak Sun Hours are explained below. It is also obtainable for most areas from various Internet sites, but whilst there if you search hard enough for it, it is surprisingly hard to locate for the USA. (If any American reader is having problems re this, email me your latitude and longitude plus nearest city and I'll try to assist).
Ideally solar modules should face the sun, but flat roof mounting is surprisingly effective. Whilst modules can be carried loose, they are readily stolen. In my experience it is not worth arranging for tilting or tracking systems except in the extreme south of Australia, or the more northern part of the USA. Adding about 20% more module capacity will make up for any loss.
Heavy cloud and rain cuts output by 50% or more. The highest output is typically on bright days with scattered low cloud. The sun shines down, is reflected from earth and bounced down again from those clouds.
Because most modules are heat-sensitive it pays to mount them so there's an air space beneath. Less important with Uni-Solar and Solarex Millenium, but air space provides useful heat insulation in the vehicle.

Technical Stuff
Solar modules are tested using 'Standard Operating Conditions.'
These specify cell temperature of 25 degrees C. Note that this does not mean ambient temperature. It is the actual temperature of the cells, and in sunlight this corresponds to about 5 degrees C.
The output of solar modules is obtained by plotting curves of voltage and current and from these using whatever combination of those two parameters gives the highest 'number'. In practice this tends to between 17.0 - 18 volts. Thus a module that produces 4.7 amps at 17 volts is rated at 80 watts.
Power being P = IV, that module will produce 56.4 watts at 12 volts - and 65.8 volts at 14 volts.
In other words module output is partially a function of the voltage developed across the load.
The industry's 'Standard Operating Conditions' (SOC) measures output at a cell (not ambient) temperature of 25 degrees C at an irradiance of 1 kW sq.m. As this equates to an ambient temperature close to 0 degrees C, the SOC may better be regarded as 'Standard Test Conditions'.
Manufacturers do however also quote a separate NOCT (Nominal Operating Condition Temperature).
This gives an indication of the actual cell temperature at 20 degrees C ambient, but at 80% of the irradiance of SOC operating conditions, a wind speed of 1 m.s, and the back of the module enclosure open to atmosphere. Under these conditions the NOCT is typically 47-49 degrees C. temperature - or looking at it another way, the cell is likely to be 25-30 degrees C hotter than ambient temperature.
Mono- and poly-crystalline modules lose output at a rate of approximately 0.4%-0.5% per degree C above about 5 degrees C (voltage drops considerably, current rises slightly). Thus at 30 degrees C ambient, output of modules using that technology is likely to be 15% down (ie. over and above the loss due to working at 12-14 volts).
Amorphous technology modules (Uni-Solar/Solarex Millenium) tend to be increase output very slightly with rising temperature.
The current output of modules is usually shown in the technical data. It may be shown as ISC (short circuit current), or as operating current. The latter is the figure to use. True output is the operating current times the operating voltage. It must then be corrected for temperature.

This is actual data from the rear panel of an 80-watt module.

Whilst it is rare for modules to produce their full rated output (Pmax) it is possible to achieve it (or very close to it) when driving a load (such as a water pump) that will operate at the voltage at which peak output was tested. It can also be achieved by using multi-point tracking systems that, in effect act as an 'electrical torque converter' and 'swap volts for amps' (actually a dc/dc converter). So whilst people tend to be confused by the rating system, it's both technically credible and legal.
The term Peak Sun Hours (PSH) is not my invention! It's used extensively in the photo-voltaic industry but does not seem widely known by engineers in other disciplines. In effect it's the number of hours of midday sun on a clear day equivalent to the irradiation for that day. One Peak Sun Hour equals 1 kilowatt/hour/square metre.
Full details of what can be run from solar, required module and battery capacity, installation (probably rather more than you wanted to know!) are in my books - and in brief on my website.
This article is copyright Collyn Rivers, Broome 2003. Email: collynr@bigpond.com
www.caravanandmotorhomebooks.com. It may reproduced on non-commercial Internet sites free of charge providing this last paragraph, including addresses, is included in full.

Re watts. These are generally easier to work with as you can discuss electrical energy without needing continually to quote the voltage.

One watt is one amp times one volt. So to convert watts into amps in my article, divide by 12. Thus 58 watts (in a 12 volt system) is 4.833 and a lot more 3s amps).

My own 28 Uni-Solar module system produces a maximum of 12,000 watts hr/day. In terms of amps (at 12 volts) this would equate to 1000 amp.hrs/day. In practice, because it's a 48-volt system with inverter to 240 volt AC, it churns out 250 amp.hr/day (you see why it's easier to use watts!).

The 28-module array produces about 2% more output when its 110 degrees F, than it does at 65 degrees F (a very cold day for us).
Collyn down-under

MSN Member · March 16, 2009, 08:40 AM

Check out www.RVSolarElectric.com

mightybooboo · March 16, 2009, 08:40 AM

Just got back from my 4 day camping trip,except for a leak in rear window(that was new) all went well.Got the solar tested in real time. Im 150/watts ,8.9amps max. Pulled 8.1 amps max, not bad for flat mounted panels. My shortcoming is having 1 12volt battery, need more amp/hr storage, panels had no trouble keeping the batt fully charged. The batt problem is where to mount em, compartment just sux size wise. Sounds like a welding job will be next on the power list. LOVE THAT SOLAR!!!
BooBoo

DanD2Soon · March 16, 2009, 08:41 AM

Sent: 4/5/2004 7:57 PM

Several years ago, I finally jumped into solar with both feet (after nearly a year of research & penny pinching) I tried to read everything I could find about PV (Photovoltaic) Panels, battery Banks, Inverters, Charge controllers, system sizing, wiring techniques, tilt vs flat mounting and the dozens of other questions that pop into your mind while you're reading. I found Phreds poop sheets and Bill Laudeman's comments (ClassicRv Advocate) real helps in getting me started on the right path. Also advice from RV Solar, Northern Arizona Wind & Sun, Home Power Magazine and Great Lakes Energy Systems. All had tons of useful info online just for the reading. Theirs & other links appear at the bottom of this message.

I bought my system components from folks who know RV applications and are readily available at the other end of a phone line, and I followed their installation instructions as close to a "T" as possible. When in doubt, Err'd in favor of safety - in other words - Used heavier wire, smaller fuses, dielectric grease on every electrical connection, etc. I have a heap more money in my power system than I paid for the 2 Soon & not sorry about a dime of it. Like Ron Popeil says, I "Set it & forget it."

My onboard inventory includes:

Battery Bank - 8 Trojan T-105 6Volt batteries with "water miser" battery caps connected as 4 sets of 2 @ 12VDC (880 AmpHours) with 4/0 copper welding cable. Water Miser caps recombine the explosive hydrogen and carbon dioxide gasses back into water before it gets out of the battery - I check the water every couple of weeks but seldom have to add any.

Solar Panels - 5 Kyocera Panels: 2-120Watt originally installed in spring 2002 & 3-125Watt added a year later in spring 2003 - 615Watts rated total. Actual output is about 35 Amps @ 17 VDC most of the daylight hours typically putting 300-350 AmpHours back into the battery bank.

Charge Controller - Trace C-40 Regulator - chose this 40 Amp controller from the git-go to allow for planned 5-120W panels whose theoretical output would be 35.5 Amps. A good charge controller is a must between your panels & batteries - will charge them correctly, even equalize them, and never "fry" them!!!

Inverter/Charger - Heart (now Xantrex) Freedom 30 - 3,000 Watt (3 KW) combination inverter & 140 Amp charger. 3KW continuous output is equal to my Kohler Genset. All external 110 vac power whether Shoreline or Genset goes through this unit. When you are plugged in or on the generator, that power "passes through" this inverter and it "taps off" a portion of the supply to run its Battery charger - IF that external power is interrupted (i.e. somebody pulls the plug) the inverter picks up the load so fast that our TV picture doesn't even flicker. And when plugged into Shoreline or Genset it recharges Batteries at as high as 140 Amps with a fully automatic 3 stage tapered charge so as not to "Fry" them. This unit also has the ability to Equalize the batteries - really important to long Wet Cell Lead-Acid Battery Life.

Remote - Heart Link 1000 Model - REALLY is the HEART of the system - Monitors system, controls inverter/charger functions & displays system status. Good remotes can be bought @ $150, the Link 1000 is $300+ - Programmable, it comes preset (default base settings) for all kinds of system parameters, it senses battery temperature and adjusts charging for battery temp, type & bank size, Inverter Temp, a battery saving shutdown voltage feature (will shut down the inverter at a safe level of bank usage instead of draining them dead), has L.E.D. digital display that will monitor, amps in/out, Amp Hours remaining, Chassis Battery voltage, etc.

More than you wanted to know maybe - Less than you need to know maybe.

The system is sized such that the useable portion of the battery bank (usually between 1/3 & 1/2 of the 880 AmpHours = 290-400 AmpHours) can be replaced by daily solar collection capacity and if collection is reduced because it's cloudy, we just use a little less power or run the Genset for a while to make up the difference. I can park wherever I want without external power, in relative silence - What a joy! We're careful with power, but don't hesitate to use whatever we want, Microwave, TV, Frig, lights, computer, (Net. connected through cell phone), scanner, coffeemaker, vacuum - it's nice! Real Nice! I have $4978 in this system and wouldn't trade the Freedom it provides for anything else I can think of.

I used the 2 SOON to live in when I travel away from home as an IBEW electrician making me a Part-time Full Timer. So when it's hot out, I'm done working and in need of a shower, boondocking along a river, listening to the towboat skippers on the marine channels, and watching herons & eagles fly by... I've been known to turn on the A/C for an hour or so, while I shower, dry off, get a cool one out of the frig, put my feet up and "shake off" the day. Man! Ain't technology something?

All that said, hope it stirs others to share their system experience/woes - always glad to help any way I can - Useful links below...

Solar

General:

Phed's Poop Sheets - Index http://phrannie.org/phredex.html

Panels:

Sierra Solar Systems Online Store http://www.sierrasolar.com/index.html

Systems:

Home Power Magazine: Home Page http://www.homepower.com/
RV Solar Electric Inc: http://www.rvsolarelectric.com/
Alternative Energy Systems - Great Lakes: http://www.greatlakes-energy.com/
The Solar System http://www.mrsharkey.com/solar.htm
Noel's Package http://www.rvsolarelectric.com/package.htm

Laplaya · March 16, 2009, 08:41 AM

I too have been peeking into solar/led stuff. Originally for our sailboat but after having purchased our unnamed & unsexed Winnie I am thinking about applications for that as well.
For anyone interested I found a decent site (in Canada) that has lots of equipment as well as real people on the other end of the phone !!
They also say somewhere that they love a challenge and to give em a call.
Here's the addy.
http://www.wsetech.com/businessprofile.php

AL

ibdilbert01 · March 16, 2009, 08:41 AM

"Battery Bank - 8 Trojan T-105 6Volt batteries"

Where did you manage to place these in your RV?

MSN Member · March 16, 2009, 08:41 AM

Thats a lot of batterys,I've run up to 4 for the house/inverter system.I use the charger thats built-in the inverter when pluged in or the engine alternator when driving to charge the battery bank.This works out good for how I use my motorhome.A Heart Freedom inverter has been running in my 1970 F-17 bago for over 10 years and works great.The OEM AC to DC converter was bad anyways,now I don't have one or need one.I love the freedom to park anywhere and and have AC power with out a generator running.

DanD2Soon · March 16, 2009, 08:42 AM

Hey Gang,

I thought I had put a link to the battery bank project photos in here somewhere, but I can't find it either - so here it is: http://rides.webshots.com/album/552091800woWBis This project album was put on my webshots pages back when our CW pages / MSN accounts were limited. Now that we have the space, I will attempt to copy it over to my albums here on CW soon. Meanwhile, this hint, Most of the webshots photos are High Resolution and can be viewed in really great full screen detail if you click on the "Full size" heading at the top right of the frame - your Browser Back Button returns you to the album.

Also - I just checked all the clickable hot links in Reply #14 & they're all working - surfing those links will start anyone a great education in solar/wind/alternative power.

Good Luck - DanD

ibdilbert01 · March 16, 2009, 08:42 AM

DanD, wow, that looks like a perfect setup!!!! I'm very impressed! I just bought 2 uni-solar 64s, and plan to buy two more. My original plans were to just have two or four golf cart batteries. I'm looking at controllers now, probably will go with a MPPT controller if I can find the pocket change. I live with a financially embarrassed checking account.

DanD2Soon · March 16, 2009, 08:42 AM

Sounds like a plan, Tim. Curious about using the thin-film 64's instead of higher wattage conventionals. Keep us posted & pictures! We're all pulling for you.

ibdilbert01 · March 16, 2009, 08:43 AM

"Curious about using the thin-film 64's"

Well, probably a mistake on my part, due to lack of experience and to be all honest, there is a lot of information on solar setups, but not much on the durability let alone real life experience. The unisolars are advertised as unbreakable, and seem to rate fairly well in shaded areas. However they rate poor in watt per size. Not thinking of how many obstacles are on the roof of my winnie, I assumed I had plenty of space to work with. My assumption as normal was a bit off considering the uni-solar 64 watt panels are 4.5 feet tall, and 2.5 feet wide. I want a total of 4 on the roof, and I do have the space, but that leaves me with not much room to grow. I'm amazed how much solar panels cost, this can become an expensive hobby.

DanD2Soon · March 16, 2009, 08:43 AM

Tim, There's no such thing as wrong with these things - There's just different ways to get there! Don't worry about it - you've made a start & that's great!

You're right. I thought there was a lot of clear space up on the roof until I started looking for places to put the panels. tehe & ohwell. Most modern PV panels have built-in reverse current protection diodes so they can be hooked in parallel without worries about one backfeeding another which also means you can mix & match panel types. Your charge controller couldn't care less where the current is coming from as long as it doesn't exceed the controller's rating. So - If sometime in the future, you chose to add one or two 135 watt panels to the two 64's you have, all that's needed is to splice their output into your existing controller feed. The important thing at this point is to save up that "pocket change" until you can afford to get a charge controller that is sized to what you want your future system to be - It's well worth the wait! If your roof can hold 4-64's it could also hold 2-64's + 2-135's, or it could hold 4-135's. Roughly (4-64's) = 16 amps | (2-64's + 2-135's) = 23 amps | (4-135's) = 30 amps. All I'm suggesting is that with the 2-64's you already have, a 25 Amp charge controller would easily handle what you have now , Plus giving you the option of adding 2 more of whatever you can afford or will fit. And or course a 30 or 35 Amp controller would allow for any possible configuration you could bolt to your roof. Ah - the dreams!

Not so pretty, but here's a pic of 2 Soons' roof - http://www.classicwinnebagos.org/Coppermine/displayimage.php?album=76&pos=8

ibdilbert01 · March 16, 2009, 08:43 AM

I went ahead and took your advice on the controller and bought a 30 amp for future growth. Doing a little research I found out that I could use a multi meter to test the panels output in amps. Each panel showed about 21.5 volts, and about 3.3 amps. The controller I bought is a MPPT style and its input can be anything from 12 to 60 volts and can be configured for a 12 volt battery pack. I'm thinking about mounting the uni-solar panels near the back of the RV, as this summer I will also take your advice and buy two higher wattage style panels and will want to mount them in the front. I have a feeling solar can be addictive.

DanD2Soon · March 16, 2009, 12:56 PM

No doubt about Solar addiction! It's similar to the one we all catch when we get caught up in our "Classic" RV beasts...

Solar technology is growing by leaps & bounds and although I'm happy as a clam with it, my system is 7 years OLD. I've been reading about your MPPT controller technology - really cool - don't think it was nearly as advanced or even available when I assembled this system. Keep us posted on your progress - You're fast becoming our new Solar Guru!