Okay,
Here's the final verdict, after some adjustments to the system while at OSH. I was charging the iPhone, camcorder batteries, and running a fan so I could stay cool in the tent.
One of these (
http://www.blackanddecker.com/ProductGuide/Product-Details.aspx?ProductID=16346 ) booster batteries is great for a portable 12V source for charging cellphones. It has a lighter socket built-in. You can get them for about $30 online (thru amazon.com, etc).
I bought the aforementioned Black and Decker battery booster with the 12V socket and also a solar panel, thinking I'd use the solar panel to keep the booster charged. Problem #1: The booster refuses to allow you to charge it and use it simultaneously. I also don't know how on earth it could possibly charge up a car battery - It was only able to run a small battery-powered fan for three hours before it ran out of juice (yes, fully charged). Then, after I charged it again, it only charged the iPhone three times before it choked again. It was useful, but not nearly as much as I'd hoped. I'll continue to use it, but I was disappointed. Again, no WAY this is gonna really get a car going unless the car is very close to turning over on its own. I'm not taking the jumper cables out of my trunk any time soon.
Diana,
Take one of these with you, then you can charge the iphone off the plane and keep the plane battery charged with this.
http://cgi.ebay.com/12-Volt-Solar-B...ryZ79845QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
Ixnay, no way. Not nearly enough power output to really do anything meaningful. It'll keep a car battery with no load on it full, but not much else. 1.7 watts? My laptop's power adapter is 85 watts.
Back when usenet was actually usable I got this idea (briefcase solar cells) from one of the guys there:
http://home.fuse.net/tjmcquinn/campMcQuinnGoesGreen.jpg
I bring a decent 12 volt rechargeable battery and just charge it during the day. Last year we were there 8 days and had all the power we needed.
The solar panel I use is on ebay too:
http://tinyurl.com/6mukg4
But I have to admit I have never tested it by letting my gel cell run all the way down and seeing how long it takes to recharge. It's entirely possible that most or all of the power I need comes with me!
And, we have a winner! I bought this one too. 15 watts IIRC, almost 10x the ones linked elsewhere in the thread, and 3x the one that Target had for the same price. And, it worked GREAT. Even though the B&D booster refused to charge off it, I ended up using it for the camcorder batteries when I was away from the campsite. I used it for the iPhone the one time I was briefly back at camp during the day. It also worked PERFECTLY for the fan - It turned out to be pretty cold at night this year so I didn't need it, but I faced the panels east and plugged the fan in, so when the sun came up and the tent started to get hot, the fan would just come right on. The panels also were able to run the fan, albeit a bit slowly, even before the sun actually rose. All in all, I'm happiest with the purchase of the briefcase solar panel out of all the power-related junk I had. Thanks for the tip, Tom!
Diana, the warbird volunteer camping area is adding several "power panels" around its periphery this year just for cell phone and laptop charging. I wouldn't be surprised if the North 40 did the same. If all else fails we'd be happy to have it charged for you. Mary or Kathleen could get it to you when it was fully charged if I'm out of pocket.
I don't know if it was there last year, but there was a little pole (looked like one of those little phone company boxes that you see out by the road in some areas) that had 4 outlets on it next to the shower trailer up by the Hilton. Partway through the week, EAA brought a pair of power strips up there due to its popularity. Good job, EAA.
This is the cheapest method for using the12V while on the road.
http://cgi.ebay.com/ebaymotors/Part...hash=item200238860507&_trksid=p3286.m14.l1318
It is a well constructed battery charger that came on VW and Audi cars. It will plug into your ligher socket, if it's hot will keep the battery up. If the lighter socket is not hot with the master off, then you can get a simple lighter to alligtor clip and clip it right to the batt. Radio Shack has them for a few bucks.
I use it on my boat and plane. Just clip it to the batt, and aim at the sun. In summer, you get quite a few hours of energy out of them. You should turn off the elec T&B so as not to run it when the master is on.
Again, OK as a battery maintainer, but I was using every bit of the 15 watts off the briefcase panel to do anything useful. The smaller panels like this just wouldn't work well enough.
Thanks to everyone for the suggestions! I was able to power everything without a generator, and now I feel "green" since I own a solar panel.