Portable Solar Chargers

[Ultra Swain]

Just in time for the rainy season I need to purchase some portable solar chargers for my laptop and video cameras. Any suggestions?

[Mikethehack]

Brunton Solar Roll works well. However, it gets a bit technical cos it depends on the kinds of batteries you are using, plus local light conditions, temps etc. We would use a solar power geek to cobble together stuff for us for our various bits and bobs. He said the only place they work properly is at either pole, otherwise they are not very effective.

Probably better off using a car charger. Cheaper too.

[thewalrus]

If you have access to a car (or any 12V lead acid battery), a car charger works great...

Since I started using solar power for off-grid telecom sites I have been maintaining a spreadsheet with basic information about portable (and non-portable, like 210W to 280W monocrystalline modules) solar systems. Here is a screenshot cut and paste from the section about portable thin film. In the US domestic market you can buy Powerfilm, Global Solar or Brunton. There are varying choices on whether you want rolling or folding. The $/watt is generally quite high for something like the Powerfilm 20W or 30W folder so you should be certain you really need it.

One thing to keep in mind is that you should not charge some batteries directly from these, you can fuck up a lead acid deep cycle battery by overcharging it. In some applications with a DC-DC power supply you can charge things directly from the panel (small laptops, Iridium phones, etc). If you are charging a 50aH, 100aH sized car battery you'll want a solar charge controller (look at the small charge controllers at www.sunelec.com for example).

The Powerfilm 10W, 20W, 30W can be connected in parallel for increased amperage at about 17V.

Sorry for the width of the spreadsheet, scroll right for all columns.

http://i.imgur.com/etfYC.png

[thewalrus]

Err... Looking at that I just realized there's a lot of 'raw' cells in the list there, what you care about are ready to use laminated modules, so I've hidden the irrelevant rows and taken another screenshot.

Other than the form factor that you prefer (rollable or folding), look at these columns:

$/watt
watts/kilogram
watt/square meter

Portable thin film foldable modules have shit economics right now, the only thing they win on is portability. Cheap 180W solar panels should perform at about 135W/square meter at standard test conditions, thin film folding panels are lucky to achieve 35 watts per square meter. The $/watt ratio is also above $12/watt when cheap glass panels are under $2/watt. If you can find some place selling the standard glass encapsulated modules from China and lash one to a hut's rooftop it'll probably cost you a lot less than buying a $350 folding thing and having it shipped from the USA. But if it absolutely needs to go in a backpack, that's moot.

Here's the new version:

http://i.imgur.com/uC4zt.png

[rickshaw92]

Take yo racist ass down to radio shack and what ever ya do try not to be a bitch.

[Ultra Swain]

I am looking at being nowhere near a generator, inverter, car battery, etc for a couple weeks. So will will need to go solar. As you can probably tell I have no previous experience with any of this gear, thanks for the help.

[Ultra Swain]

If you have access to a car (or any 12V lead acid battery), a car charger works great...

Since I started using solar power for off-grid telecom sites I have been maintaining a spreadsheet with basic information about portable (and non-portable, like 210W to 280W monocrystalline modules) solar systems. Here is a screenshot cut and paste from the section about portable thin film. In the US domestic market you can buy Powerfilm, Global Solar or Brunton. There are varying choices on whether you want rolling or folding. The $/watt is generally quite high for something like the Powerfilm 20W or 30W folder so you should be certain you really need it.

One thing to keep in mind is that you should not charge some batteries directly from these, you can fuck up a lead acid deep cycle battery by overcharging it. In some applications with a DC-DC power supply you can charge things directly from the panel (small laptops, Iridium phones, etc). If you are charging a 50aH, 100aH sized car battery you'll want a solar charge controller (look at the small charge controllers at http://www.sunelec.com for example).

The Powerfilm 10W, 20W, 30W can be connected in parallel for increased amperage at about 17V.

Sorry for the width of the spreadsheet, scroll right for all columns.

http://i.imgur.com/etfYC.png

You are about the single most useful person on the planet, seriously.

[Ultra Swain]

Take yo racist ass down to radio shack and what ever ya do try not to be a bitch.

If you don't pipe the fuck down, I will make you sew a yellow rickshaw to your shirt and gas you, bitch.