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Topic: (solar) too good to be true (Read 1701 times) previous topic - next topic

Re: (solar) too good to be true

Reply #25 –
Last week, on a hot sunny afternoon, I did shoot the panels with an ir gun. They were running around 130 degrees while a black car was just under 160.
Tom Lang K6PG (originally  KC6UEC)
and Diane Lang
2003 38 U295 build 6209
2016 Jeep Grand Cherokee Summit Ecodiesel
still have tow-ready 2006 Acura MDX 
Temple City, California
Motorcade 16681 California Chapter President
SKP 16663 member of SKP Park of the Sierra, Coarsegold California
FMCA F071251
Retired electrical and electronic engineer

Re: (solar) too good to be true

Reply #26 –
Quote from: Tom Lang –
Last week, on a hot sunny afternoon, I did shoot the panels with an ir gun. They were running around 130 degrees while a black car was just under 160.

That's interesting!!! Now all we need is for someone to drive their rig around for a couple hours at 60mph (preferably with a headwind) and see how well they stay put. :P

Thanks, Tom :)

Craig
1993 U225 36' Unihome GV with PACBRAKE exhaust retarder, Banks Stinger and Solar Panels.
Toad: 1999 Jeep Wrangler 2-door soft-top.

"No one has ever had to evacuate a city because the solar panels broke."

Re: (solar) too good to be true

Reply #27 –
Quote from: acousticart –
... the plan is to wash the roof, and then buff with a fine silicon free compound, wipe the roof with acetone before installing the panels and finally roll them out with a vinyl flooring roller....

I've been trying to find something to do the buffing with. Everything I've looked at contains some sort of waxing agent which I am pretty sure I don't want for the installation of solar panels; either self-stick or tape.

Have you found the compound you plan to use, yet?

Craig
1993 U225 36' Unihome GV with PACBRAKE exhaust retarder, Banks Stinger and Solar Panels.
Toad: 1999 Jeep Wrangler 2-door soft-top.

"No one has ever had to evacuate a city because the solar panels broke."

Re: (solar) too good to be true

Reply #28 –
Meguiars professional products are silicone free and body shop/paint shop safe according to their website and the automotive paint supply store where I bought mine. I don't believe that the cutting compound available in many grits from superfine to fast cutting has any waxing agent, but since I will be doing a acetone wipe down, I am not too worried about it. Autobody repair and paint shops generally don't want silicone anywhere near their paint booths for obvious reasons!
Don
Quote from: wa_desert_rat –
I've been trying to find something to do the buffing with. Everything I've looked at contains some sort of waxing agent which I am pretty sure I don't want for the installation of solar panels; either self-stick or tape.

Have you found the compound you plan to use, yet?

Craig
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Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: (solar) too good to be true

Reply #29 –
Thanks, Don. I figured it would be a Meguires product but none of the auto stores here (small town) had anything that looked like what I needed. Another addition to the Amazon shopping list...

Craig
1993 U225 36' Unihome GV with PACBRAKE exhaust retarder, Banks Stinger and Solar Panels.
Toad: 1999 Jeep Wrangler 2-door soft-top.

"No one has ever had to evacuate a city because the solar panels broke."

Re: (solar) too good to be true

Reply #30 –
I like the idea that Unisolar panels provide more power then other panels when the sun is low in the sky. I do not like the price. I recently bought 1200 watts at less than $1.00 per watt.

You will need to pair (in series) the Unisolar 68 watt and the Global panels to match the voltage of the Unisolar 136 watt.

You will also require a solar charge controller which can accommodate at least 50 VOC and not all controllers can do this, so check the controller you are buying.

If you have an odd number of the lower voltage panels, you could run separate wires down to the outside fridge door and use the power to charge other 6 or 12 volt batteries. I have done this with three 55watt panels and run the ceiling fan or charge spare batteries (flooded/sealed 6v or 12v or even 1.5volt AA). It is possible to charge 6 volt batteries as long as you are not charging with more amps than the battery can accommodate. Matching panel and battery voltage does not matter when you connect the panels directly to a battery (no controller). The panels will work at battery voltage and will never provide more than "short circuit amps". Incidentally, they will not provide their rated wattage because the panel voltage is below VMP.
Wyatt
96 U320 40 WTFE, build 4943
84 Toyota Supra towd
2015 Jeep Wrangler towd
Victoria, BC, Canada

Re: (solar) too good to be true

Reply #31 –
If you want to series all your panels to bring high voltage (circa 150v) off the roof be aware of that a short due to insulation wear will result in welding things together with no end until the sun goes down.

Also note that, as the input voltage to a solar controller goes up, the efficiency of the controller goes down. The big plus side is that as the voltage goes up, the line loss goes down and you can use lighter wires.

I have an odd number of 28 VMP panels so did not pair them.
Wyatt
96 U320 40 WTFE, build 4943
84 Toyota Supra towd
2015 Jeep Wrangler towd
Victoria, BC, Canada

Re: (solar) too good to be true

Reply #32 –
Quote from: wa_desert_rat –
That's interesting!!! Now all we need is for someone to drive their rig around for a couple hours at 60mph (preferably with a headwind) and see how well they stay put. :P

Thanks, Tom :)

Craig


Well, since you ask...I am almost back home now, from Los Angeles to north of San Francisco and back, often at 60-65 mph with  a variety of winds. The panels haven't budged.
Tom Lang K6PG (originally  KC6UEC)
and Diane Lang
2003 38 U295 build 6209
2016 Jeep Grand Cherokee Summit Ecodiesel
still have tow-ready 2006 Acura MDX 
Temple City, California
Motorcade 16681 California Chapter President
SKP 16663 member of SKP Park of the Sierra, Coarsegold California
FMCA F071251
Retired electrical and electronic engineer

Re: (solar) too good to be true

Reply #33 –
Here's a quick update on too good to be true.

It was too good, and not true.

It appears my charge controller's current monitor needed a few cycles to find it's limits. It was consistently reading 4 Amps too high for the first week. Now it is reading correctly, including zero Amps after dark.

As an aside, I really like having the Tri-Metric 2020 on board. I now know ihe coach is using 2A at night with everything off except the refrigerator. I now know the Prosine inverter is a power hog even with the TV off. And I know for real how power hungry my fluorescent lamps are compared to the LEDs.

Having fun here.
Tom Lang K6PG (originally  KC6UEC)
and Diane Lang
2003 38 U295 build 6209
2016 Jeep Grand Cherokee Summit Ecodiesel
still have tow-ready 2006 Acura MDX 
Temple City, California
Motorcade 16681 California Chapter President
SKP 16663 member of SKP Park of the Sierra, Coarsegold California
FMCA F071251
Retired electrical and electronic engineer