45 Watt Solar Charging system from Harbor Freight

[johnt55]

Amorphous solar panels, like Harbor Freight's, are good where space is not a consideration - like covering the entire roof of a house. In quantity, amorphous panels can be real cheap - less than $2.00/watt, but the conversion efficiency and amperage is much lower. I'm sure this technology will improve a lot in the future. Recently, the price of raw silicon has dropped from almost $1000.00/lb to less than $100.00/lb., so prices for mono and poly-crystalline have dropped considerably.
_________________
81' AC Westy

[The Raven]

Like everything, you get what you pay for. HF although a great source for throw away tools, is not someplace you go to if you want something that will last.

IF you don't have time to do something right the first time, do you think you will have the time to fix it?

Spend the money, get quality, and be done with it.

[PDXWesty]

The only problem I have with the harbor freight solar panels is their size and efficiency. They are huge for the power output they offer which means they have a very low efficiency. Solar panels have come down so much in price in recent years that these are not that great a deal anymore.

The size of the HF panels are 12"x36" and 15 watts each.
That's 432 sq.in./15 watts or 28.8 sq.in/1watt

A similar 50 watt monocrystaline panel is 21"x30" and 50 watts.
That's 630 sq.in./50 watts or 12.6 sq.in./1 watt

You can see that this 50 watt panel is more than 200% more efficient than the HF panel, and it costs relitively the same amount.

http://www.amazon.com/HQRP-Mono-crystalline-Anodiz...mp;sr=8-16

If you compare costs on a $/watt basis, the HF panel is $4/watt. The panel at Amazon is $3.76/watt

There is also a 100 watt panel for $319. You can do the math on that one and see how cheap it really is. (hint: $3.19/watt)

http://www.amazon.com/Instapark%C2%AE-100W-Mono-cr...amp;sr=8-7

There's a lot of good deals out there for better quality products.
_________________
89 Westy 2.1 Auto

[johnt55]

What Ahwahnee did looks pretty neat!

If you're looking for a low cost way to go solar, the Harbor Freight panels are not a bad idea at all. Cheap, light weight, appear well-made except for the leads from the panel and come complete with a regulator and the two light bulbs. Like Ahwahnee's setup, one of those panels should fit snugly in the luggage rack. I understand that they will sell just one panel and not the whole kit if that's all you need. If you're using just one panel and you don't use the regulator that comes with the complete $150.00 kit, remember to disconnect the panel from the battery when the sun goes down, or add a cheap Radio Shack diode to the circuit, (fifty cents?). Otherwise, the panel will actually discharge the battery at night. Without some sun the panel becomes a circuit load like a fan, or a light, etc.

I have an older 5 watt Harbor Freight panel, (that one of my kids actually drove into it with her car - still works!) connected to an old motorcycle battery which keeps one of those 12 volt car fans running most of the day. So, for that kind of limited use application it's perfect.

Here's a photo of a poly-silicone panel I made which puts out about 60 watts on a sunny day.

https://www.thesamba.com/vw/gallery/pix/855103.jpg

I've seen photos of Westys where they've covered just about the entire roof with panels.

Anything you can use that works directly on 12 volts is best. Even the very best DC/AC inverters loose energy in the conversion process. Of course, the best power source of all is the alternator or generator on the engine - those things pump out a lot of juice, more than the van's battery ever needs. Tap into that source when you're running and you can quickly charge-up or run most anything.
_________________
81' AC Westy

[joseph928]

If you dont have the money hp is kind of ok.I've got 2 5watt panels well its only 10 watts but they are about 1 sq. foot each and will run my lights or a small fan or my little digital tv. They fit on my yakima rack used 4 yakima clamps looks good and holds them at about 30 degrees makes me happy. Best of all I only spent less than $80.00 on it all.
_________________
1987 syncro westy tin top sun roof , GW2.3, rear locker, decoupler, Gary Lee tire rack & winch mount, lift, south african grill, big brakes , rhein alloy ,15 BFG AT, Fiamma 10 foot awning ,140 watt rear 85 watt front solar , mppt, truckfridge, automatic fire extinguishing system, tencent oil cooler, And a RMW SS exhaust! - 1971 bug convertible 1776 engine- 2010 Subaru turbo - 1993 Toyota 4x4 truck - 1999 Harley 95 CI, big bore, Andrews cams . Also 80-84- vans. Stock 65 sunroof bug.

[mtwrench540]

[what happend to 12.6 volts as fully charged? 14V is only surface charge!quote="johnt55"]Here's a simple, real-world example of the output of the HF panels.

I have two sets of the HF 45 watt panels mounted on the roof behind my garage, remnants of my early experimental phase. Supposedly 90 watts total, right? I have them both connected to a large, deep cell ChinaMart battery inside the garage. (Regular car batteries don't like to be completely discharged and charged.)

Using those panels, it takes about 1 to 1.5 weeks to charge that battery from about 11.5 volts, (discharged state) to a fully charged, (14+ volts) state. And I live in SoCal with lots of sun! Of course, it makes no sense to connect those panels to such a large battery and expect them to do much, but until I figure out another use for them...oh well.

BTW, unless you're charging a very small battery, the panels can be set up without the regulator which uses some current itself - no chance you'll overcharge something. If you do, place a diode in the circuit. Otherwise the panels will actually discharge your battery at night!

Also, the power leads from the HF panels are pre-wired with what looks like cheap speaker wire which should be replaced - a big no-no for the DC current they put out. That said, they DO work. And with a coupon, a set can be had for $150.00. The two, 5 watt, 12 volt compact fluorescent bulbs that ship with the package are amazing. Just one can light up the entire inside of a Westy. With two going, you'd think you were in a trendy, but extremely small restaurant![/quote]
_________________
87 wolfsberg,74 181w/1915 and lots of patina! learned to fix vw's from hot vw mag in 1964,VWOA instructor,DSM,69 to73,service mgr at different porsche-audi dealers etc,etc,now retired!!! first vw new 64,transplanted 356 eng in 65,400characters are not enough space!!

[PDXWesty]

[DrTwee]

Oh, another thing, I'd suggest considering a panel mount that can be used on the ground. That way your solar panel(s) can be aimed for optimum efficiency independent of your vehicles orientation.
_________________
1982 Vanagon Westy 1.9 Diesel NA (Mello Yellow)

[DrTwee]

Most inexpensive solar panels use amorphous silicon, which is the least efficient. If you're serious about solar, get a high quality panel using monocrystalline silicon (Kyocera is a top rated one).
_________________
1982 Vanagon Westy 1.9 Diesel NA (Mello Yellow)

[Ahwahnee]

[johnt55]

Here's a simple, real-world example of the output of the HF panels.

I have two sets of the HF 45 watt panels mounted on the roof behind my garage, remnants of my early experimental phase. Supposedly 90 watts total, right? I have them both connected to a large, deep cell ChinaMart battery inside the garage. (Regular car batteries don't like to be completely discharged and charged.)

Using those panels, it takes about 1 to 1.5 weeks to charge that battery from about 11.5 volts, (discharged state) to a fully charged, (14+ volts) state. And I live in SoCal with lots of sun! Of course, it makes no sense to connect those panels to such a large battery and expect them to do much, but until I figure out another use for them...oh well.

BTW, unless you're charging a very small battery, the panels can be set up without the regulator which uses some current itself - no chance you'll overcharge something. If you do, place a diode in the circuit. Otherwise the panels will actually discharge your battery at night!

Also, the power leads from the HF panels are pre-wired with what looks like cheap speaker wire which should be replaced - a big no-no for the DC current they put out. That said, they DO work. And with a coupon, a set can be had for $150.00. The two, 5 watt, 12 volt compact fluorescent bulbs that ship with the package are amazing. Just one can light up the entire inside of a Westy. With two going, you'd think you were in a trendy, but extremely small restaurant!
_________________
81' AC Westy

[crazyvwvanman]

No no no, way too practical, and doesn't give you anything for show and tell!

Mark
yeah I have some solar panels and sometimes they are handy to use

[IdahoDoug]

Hmm, what about using a half gallon of gasoline and your 90 amp alternator to recharge the battery on the few days a year you sit in one spot long enough to discharge? That's about $2. I know it's not green tech, but I'm just sayin......

DougM
_________________
1987 2WD Wolfsburg Vanagon Weekender "Mango", two fully locked 80 Series LandCruisers. 2017 Subaru Outback boxer. 1990 Audi 90 Quattro 20V with rear locking differential, 1990 burgundy parts Vanagon. 1984 Porsche 944, 1988 Toyota Supra 5 speed targa, 2002 BMW 325iX, 1982 Toyota Sunrader

[johnt55]

[westyventures]

The Engel uses the swing compressor, so always draws 2.0-2.5 amps. Yes, that could average out to 20-25 a/h per day. If only there were a fridge that consumed .5 amps or less when running...[propane]

[SWbySWesty]

[PDXWesty]

I think he means amp-hours.

If the fridge draws 2.5 amps while running, and runs 50% of the time, it will use 30 amp-hours per 24 hour period.

(2.5*50%)* 24 hours = 30 amp-hours/day
_________________
89 Westy 2.1 Auto

[SWbySWesty]

Nope. Direct from Engel:

Power Consumption: 0.7 - 2.5 Amps

I generally pull .5-1 amp (according to my voltminder) when the fridge turns on.
_________________
1986 Westy - Billie Jean
A Westy with a Jeep heart (Pura Vida)
www.theadventurebrigade.blogspot.com - Latest update: Johnson Valley - Nov 22, 2011

[westyventures]

Is that a misprint? 0.5 amps? Probably more like 2.5 amps.

[SWbySWesty]

No, the Engle pulls 0.5amps and runs about 25 minutes each hour. Then over a 24 hour period it uses that but just typing this I see my math is off. Oi
_________________
1986 Westy - Billie Jean
A Westy with a Jeep heart (Pura Vida)
www.theadventurebrigade.blogspot.com - Latest update: Johnson Valley - Nov 22, 2011