Something to build this weekend - portable solar-powered outlet

[paxton]

A portable solar-powered outlet!

http://www.instructables.com/id/Portable-Solar-Powered-Outlet/

Looks like a reasonable total cost, with the $0.97 garden lights providing the panels.

 

[p m]

I enjoyed reading through it.
This must be the most idiotic project I've seen so far - and I saw a lot of idiotic homebuilds in Russia.
Something to ponder:
- this guy used 35 2" x 2" solar panels (or 0.05m x 0.05m).
- in one of the best places to use it, that is desert SW USA, near the border, one can get 1kW/sq.meter of solar radiation.
- a typical efficiency of cheap solar panels is about 5-7%; we can assume 10% for enjoyment.
- all panels together would yield us 35*0.05*0.05*1*0.1 = 8.75W.
- we will ignore the efficiency of the charge controller he used, and assume it was 100%.

I can pretty much assure you that the idle power draw of the 410W continuous inverter this guy used is higher than that. So he'll be draining his 12V battery even with the box sitting on the side of the road in Yuma, Arizona, tilted towards the Sun, at noon in Summer.

 

[az_max]

I dunno. I'd rather go with a goal-zero or similar system, even if it's a little more.

 

[ROVERT]

I've been able to continuously power an 80 watt device for approximately three hours without interruption and it could have gone much longer

I'm guessing he could have run it for about another hour. Then his battery would have been dead.

He could have spent less on some cheap generator and actually had something that could produce some electricity... or just bought a high ah deep cycle battery to use with his inverter.

FWIW, there are quite a few solar trickle chargers available for virtually the same cost as his 35 solar powered garden lights and charge controller.

 

[Some Dude]

I dunno. I'd rather go with a goal-zero or similar system, even if it's a little more.

Those tings are incredibly cool, but GOOD GOD the price.

http://www.goalzero.com/shop/p/138/Yeti-1250-Solar-Generator-Kit/16:1/

 

[p m]

But look at this GoalZero specs: it lists 1200W continuous power output, yet uses a 30W solar panel. So in essence it is a we-packaged-it-for-you stack of batteries and an invertor. Solar panel is there to make its owner green-proud.

To put that into prospective: our house has a large section of the roof slanted 23 deg, facing south, and unobstructed. We had a visit from one of the solar cell companies - this company uses panels with 20-23% efficiency; the cost of the system is about $6500/kW. One kilowatt of peak power on a sunny day means ~60W average.

 

[az_max]

But look at this GoalZero specs: it lists 1200W continuous power output, yet uses a 30W solar panel. So in essence it is a we-packaged-it-for-you stack of batteries and an invertor. Solar panel is there to make its owner green-proud.

To put that into prospective: our house has a large section of the roof slanted 23 deg, facing south, and unobstructed. We had a visit from one of the solar cell companies - this company uses panels with 20-23% efficiency; the cost of the system is about $6500/kW. One kilowatt of peak power on a sunny day means ~60W average.

two 30w panels, but yeah. I see it extending the battery usage for a day or two instead of providing unlimited power for an extended trip.

I'm running a Peak jump box with a 5w harbor freight solar panel and 800w generator. The solar panel is there to just maintain a charge while I'm away from camp. Generator to run/charge stuff until 8-9pm. I have a 110-12v RV converter and battery charger so I can run 12v accessories from the generator or shore power. I try to avoid inverters because of the large amount of waste in their efficiencies. I plan to upgrade to a marine battery to give me better run time between charges. I did fine last trip with plenty of power overnight to run LED lights and a small tv.

 

[p m]

The trickle-charger application for solar panels is perfectly valid. If your battery went dead flat, a 5-10W solar panel may bring it back to a single start attempt in a long sunny day.

 

[knewsom]

I carry a solar trickle charger with me when I'm out in the middle of nowhere. Sure would suck to get up in the morning to find my battery dead and nobody to give a jump.

 

[p m]

I carry a solar trickle charger with me when I'm out in the middle of nowhere. Sure would suck to get up in the morning to find my battery dead and nobody to give a jump.

Kris, not that it would, it will - if your battery is dead in the morning, you'll spend a day babysitting that trickle charger

 

[benlittle]

Hi Peter.

 

[Some Dude]

Seems like a jump box would be better suited than a solar trickle charger. I have neither, so if the battery goes flat overnight I'm walking.

Oh hey Ben.

 

[p m]

Hi Ben and Kevin.

all this talk makes me think of how old my Disco's battery is.

 

[benlittle]

Seems like a jump box would be better suited than a solar trickle charger. I have neither, so if the battery goes flat overnight I'm walking.

Oh hey Ben.

Hi Kevin.

 

[benlittle]

Hi Ben and Kevin.

all this talk makes me think of how old my Disco's battery is.

I just upgraded from a Diehard Platinum to Marine Platinum.

 

[az_max]

Here's what $35 gets you in the way of solar panels on ebay. monocrystalline 10w solar panel.

Slightly longer than an Optima d34m. I honestly thought the panel was going to be bigger. I could easily fit 4 of these on top of the trailer for 40w charging capacity in full sun.

 

[p m]

I just upgraded from a Diehard Platinum to Marine Platinum.

Sears stores seem to be closing here left and right... I only know of one left in my 'hood.

Speaking of a $35 buy... not bad at all. Comes up to $3500/kW, which is about a half what local companies charge for rooftop solar panels.