... I guess I gotta go earlier and bring more batteries for the headlight
I don't know how feasible it would be for you... but instead of carrying 400 lbs of spare batteries might look into rechargeables and one of those solar chargers gadgets. I know they sell them... and they're fairly lightweight. It would save weight on having to carry 3 weeks worth of spare batteries that are going to fizz out quickly in the cold weather.
I have gone through the solar charger phase and it has been shelved with all the other gear labeled "sell on ebay"
I went through this 2 years ago to power an HD camcorder on the trail that ran on expensive rechargeable batteries I didn't want to put into depots. So I bought a $300+ Brunton SolarRoll - 9 watts output, about 3 square feet, 12V cig lighter plug, you just add your 12V car chargers for whatever you want to charge. Well, in theory, I was all set - it worked on my patio. In real life use on the JMT in July, things were a little more problematic. Just to charge two AA batteries, I had to stop for 4 hours during the middle of the day, moving the charger along on the ground to keep it as perfectly 90 degrees to the sun as possible to maintain max output. Then when the AA charger said it was all done, these batteries lasted about half as long as a regular pair of alkaline batteries, which in turn only last 1/4th the time a Lithium battery lasts that weighs less than half of the alkaline type.
The weight of all the charging gear I had with me in 2008 is equivalent to about 40 AA Lithiums. Even with heavy use in my camera and GPS, we used a total of about 25 last summer, plus we had them in the depots, so we never carried more than 10. The weight of these things is 14 grams a piece, or two per ounce. Hold an 8-pack of alkalines and you get the idea of how much power that ounce packs. Example - Garmin 60csx GPS will run about 18 hours on a pair of Duracell AA in power saver mode. With the Lithiums, I get 60-70 hours before I need to change them.
Anyone looking for a good deal on a Brunton SolarRoll? Used on one hike, mint ;-) Great for base camp bums.
The sled idea, based on the info just above your post, may also have to be abandoned. Amazing that all these new ideas tend to go up in smoke once you dig in deeper and it all boils down to traditonal gear and modes of transportation being close to ideal. At least with the battery power thing I have first hand experience and know what worked best for me.
